Methodology Development for Capturing Co2 and Precursor Gases of Greenhouse Effect From the Exhaust of Flex-fuel Internal Combustion Engines

Methodology Development for Capturing Co2 and Precursor Gases of Greenhouse Effect From the Exhaust of Flex-fuel Internal Combustion Engines | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Methodology Development for Capturing Co2 and Precursor Gases of Greenhouse Effect From the Exhaust of Flex-fuel Internal Combustion Engines Theles Costa This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5798522/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Derived largely from the combustion of fuels used in automotive vehicles, CO 2 and precursor gases of greenhouse effect are important emission gases and deserve attention. This paper proposes a method to remove these gases by adsorption, through the capture and separation in exhaustion of vehicles with flex-fuel technology. The technique is feasible because it is based on the solid adsorption capacity and selectivity for CO 2 and precursor gases. The characterization of the used adsorbents, natural ZN2040 and synthetic Oxan_X, show unique characteristics, especially the surface area, adsorption at low pressures, stability to wet gases, application at high temperature, high Si/Al ratio in the crystal structure and the presence of elements such as Fe, Ca, K and S. The adsorbents were arranged in a horizontal fixed bed column, installed in the front vehicle noise muffler of the exhaust system. The Oxan_X synthetic zeolite with improved performance, showed reductions in average of 2,20% of CO 2 about 17% on the precursor gases, mainly CO, both for Gasoline 22% EAAF (Ethyl Alcohol Anhydrous Fuel) and ethanol burning. In addition, it allowed the reduction of other vehicle pollutants. In the long term, the use of vehicular fixed bed column contributes to a reduction of approximately 764000 tons of CO 2 and 23300 t of CO when the vehicle is operating with Gasoline, and 1168000 tons of CO 2 and 18000 t of CO when it is operating with Ethanol. Considering the vehicles of motorization 1.4 L to 2.0 L, and employing 2.0 kg of adsorbent. Adsorption Combustion Engine Emissions Dioxide Carbon Greenhouse Effect Zeolites Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 1. INTRODUCTION Climate changes predicted for the 21st century and the subsequent ones do not present exciting prospects. According to the projections of the Intergovernmental Panel on Climate Change (IPCC), a group funded by the United Nations Environmental Plan, if no further action is taken to reduce emissions of CO 2 and other greenhouse effect gases; around the year of 2035, the average air temperature will be 1°C higher than it was in 1990. In the year of 2100, it will increase more than 2°C (IPCC, 2000a and 2011). There are numerous technical and scientific arguments built through experiments and empirical methodological resources, which illustrate the current and modern ways to reduce greenhouse effect gas emissions by proposals of capture and adsorption of carbon dioxide and precursor gases from emissions gases in flows launched to the atmosphere by anthropogenic action, mainly through the burning of fossil fuels. There are many techniques that can be used in the separation of CO 2 from fuel gas streams, and the adsorption is the most widely used commercial operation (Yong, Mata, Rodrigues, 2001 ; Madia, Barbieri, Drioli, 1999 ). The carbon capture and storage (CCS) is the technology with the greatest potential to reduce CO 2 emissions on a large scale in the next 20 years (Strangeland, 2007 ). Economic growth in this period will not allow abandoning fossil fuels, but it should be considered the adoption of three bases: increasing of the energy efficiency of manufacturing processes, enhanced participation of renewable energy in the energy matrix and promotion of the widespread application of CCS (Carbon Capture and Storage). Much of the currently used processes for the adsorptive separation is based on the balance, using synthetic zeolites, 5A and 13X as adsorbents. In contrast, carbon molecular sieve (CMS) and 4A zeolites can separate the air based on their kinetic selectivity (Peck and Yang, 1995 ). Soares et al. ( 2007 ) investigated the equilibrium kinetics of CO 2 adsorption in Brazilian coal at low pressures. The adsorption capacity was in the range of 0.089–0.186 mmol CO 2 /g, typical values for coal with high ash content. The adsorption in a fixed bed column containing the granular carbon (0.8, 2.4 and 4.8 mm) showed that the rate of adsorption is fast and a mathematical model describing the dynamics of CO 2 adsorption on a fixed bed column was developed (Soares et al., 2007 ). The most important industrial processes of gaseous stream adsorption are associated with the adsorption in one column. Adsorbent particles are accommodated in a column and a gaseous stream containing one or more adsorbates flows through the bed (Suzuki, 1990 ; France et al., 2010 ). When the volume of the fluid begins to flow through the column, the mass transfer zone varies from 0–100% of the inlet concentration (corresponding to full saturation of the adsorbent). From a practical point of view, the saturation time is established when the adsorbed concentration in the effluent reaches 90 to 95% of the inlet concentration (Calero et al., 2009 ). The flux of a component of a control volume inwards or outward can include a large amount flux, with dispersion flux and molecular diffusion (Weber Jr. and Smith, 1987 ). The resultant differential equations that represent the variation of adsorbate concentration in both, fluid and solid phases using an equation of state can be adapted to a gaseous supply (Crittenden and Thomas, 1998 ). It is unclear how the carbon dioxide and the greenhouse effect precursor gases could be removed from car exhaust gases and other less centralized sources, but collectively important; perhaps this goal could be achieved indirectly by the use of hydrogen or electricity as an energy source, which could be produced from carbonaceous fuels, in a plant, in which CO 2 and precursor gases could be collected efficiently or, as suggested by this paper by adsorption directly in vehicular exhaust duct. The objective of this work is to develop an appropriate methodology to alleviate the emission of carbon dioxide and greenhouse effect precursor gases by the selective capture of this gas in the exhaust gaseous streams from internal combustion engines. Therefore, it means specifically to propose an innovative system for reducing emissions of greenhouse effect gases released by internal combustion engines, and evaluate the efficiency of solid commercial adsorbents, for these gases released by vehicles operating on Gasoline 22% Anhydrous Ethyl Alcohol Fuel (AEAC) and hydrated Ethanol. 2. Material and Methods In thermal engines, the amount of air is an essential factor in gases emissions, because by ranging the amount of air in the mixture of air/fuel an incomplete combustion may occur causing high concentrations of pollutants and greenhouse effect precursory gases in exhaustion. On the other hand, the complete burning of this fuel will inevitable produce amounts of CO 2 , a major greenhouse effect gas. 2.1. Infrastructure The tests were performed in a commercial production vehicle, Fiat Idea, Attractive version, 1.4 8V EVO Flex Fuel, 5 doors, kindly yielded by Fiat Chrysler Automobiles, with flicker ignition combustion engine of Otto cycle, 4 cylinders in line, transverse position, powered by gasoline or hydrated ethanol. With the aid of an experimental device for the measurement and analysis of vehicle emissions, before the installation of adsorption column in the vehicles exhaust system. 2.1.1. Vehicle's exhaust system The Fig. 1 shows the vehicle exhaust set and its main components. The front noise damper also works as a Fixed Bed Column of Horizontal Flow and its internal part is filled up with the adsorbent material for capture of CO 2 and greenhouse effect precursor gases from other exhaust gases. The front noise damper, a metallic tube set with internal division called Resonator box which receives, by spraying, the exhaustion gases for final reduction of the noise level, will also serve as exhaust gas filter. The Fixed Bed Column is located at this component of the exhaust line by filling up the rear resonance compartment with adsorbents to retain a portion of vehicle emissions. 2.2. The adsorbents used The adsorbent used in the fixed bed column of horizontal flow were ZN 2040 natural zeolite Clinoptilolita supplied by Celta Brazil and Oxan_X synthetic zeolite, supplied by Oxanyl Raos. Two different materials with similar adsorption characteristics and singular obtainment ways, one extracted directly from nature and used fresh and a material synthesized in laboratory were also tested. 2.3. Adsorbents characterization (zeolites) The characterization of the adsorbent included the semi-quantitative chemical composition by X-ray fluorescence, specific surface area measurement by N 2 Chemisorption, specific weight by Picnometry by water intrusion thermal behavior by TGA (thermogravimetric analysis); DTA (Differential thermal analysis), DSC (Differential scanning calorimetry) and crystalline phases identification by X-ray Diffraction (XRD). The equipment employed in the analysis were: a fluorescence spectrometer for x-ray dispersive Energy, brand SHIMADZU model EDX-720, adsorptometers, Quantachrome instruments, brand NEW model 1000 capacity for a range of 10 − 8 P/P0 (N 2 /77 K), picnometer of 50 ml; Shimadzu precision scale AY 220 max. 220 g/min. 0.01 g with resolution 0.0001 g. Thermobalance Shimadzu-TGA50H, thermobalance Netzsch -STA409EP, differential calorimeter Shimadzu-DSC50, Analyzer thermomechanical Shimadzu-TMA50, Analyzer DTG-60 simultaneous TG/DTA Shimadzu and an x-ray diffractometer PANalytical EMPYREAN model, equipped with copper anode tube. The analyzes were performed at the Laboratory of Materials and Chemical Analysis of Fiat Chrysler Automobiles, at the Physical Chemistry labs and X-rays of DEMET- Department of Metallurgical and Material Engineering, and in the Institute of Exact Sciences ICEX - Chemistry Department of the Federal University of Minas Gerais - UFMG. 2.4. Emissions laboratory The determinations of vehicle emissions were held at the Emissions Laboratory of the Innovation and Technology Center SENAI / FIEMG - Campus CETEC, equipped with: Chassis Dynamometer; Gases Analyzers; Sampling system for constant volume (AVL); Driver-Aid; Fuel storage chamber; Flow calibrator Laminar Flow Element type (LEF); CFO system (Critical Flow Orifice) and, A modern structure with computerized hardware or software that enable the interface and real-time transfer of results. The Figure (2) illustrates the main modules of the workbench for emission testing with assembly layout and distribution of equipment used for the analysis of vehicle emissions, the concentration of CO 2 and greenhouse effect precursor gases. From the roller dynamometer, through the collection/dilution of emission gases led to the analyzers, finishing with the records of the data analysis. Sampling of gases was performed by measuring the emissions gases real mass produced in the burning of the fuel that were released by vehicle exhaust. Sampling system with constant volume Pierburg brand CVS-CFV 30wt 3D-model comprising: Venturis of 6, 9 e 12 m³/min.; Four pair of “bags”; Heat exchanger system in the duct of the exhaust gases with GWK temperature control unit; Logotherm, Teco WDC 100.18 model; Collection system of the exhaust gases, ambient air filtration and dilution. The total volume of the mixture between exhaust gas/air dilutions was measured, and a part of this volume was continuously collected for analysis. The "bags" manufactured with specific material, were responsible for the collection of samples for the dilution air and the diluted gas emissions without changes in composition of the stored samples. 2.5. Vehicle settings Three different configurations were set up, one with the vehicle in its original condition and the other two with the adsorbents filling up the column in the front noise damper. The settings were called: Reference Column, ZN 2040 Column and Oxan_X Column. The steps for the columns preparation were: Step 1 - Preparation of two cuts (100 x 100mm) in the plate of the damper casing, for filling up the front cavity with the adsorbent, which forms the Fixed Bed Column in this region for adsorption of gases. Step 2 - To control the weights of the front noise damper before and after filling up with the adsorbent. Step 3 - The region of the resonator chamber was filled up with the adsorbent. Two kilograms (2.0 kg) for each column. After filling up the column, the cutouts in the external noise damper plate were welded. Step 4 - After finishing the preparation of the fixed bed column in the rear noise damper, this was replaced in the vehicle for the emission testing. After the assembly, the same testing was carried out with the vehicle at reference conditions, Figure (3). 2.6. Implementation of emissions testing The tests were performed according to the methods described in the NBR 6601 (ABNT, 2005) and NBR 7024 standards (ABNT, 2002) and simulated a trip of average duration, in urban areas, approximately 17.88 km on an urban cycle, and a trip of 16.40 km on a roadway cycle. The cycle was defined by a continuous chart of speed in function of time, known as the FTP-75 test. The gas collected in the vehicle is diluted in air in order to obtain a constant total flow. Part of this mixture was also collected in constant flow and stored for analysis. The levels of emission were determined by the final sample concentrations and by the mixture total volume during the stages of the cycle. 3. Results and Considerations 3.1. Adsorbents characterization As expected, in both samples, the elements silicon (Si) and aluminum (Al) are predominant. In synthetic zeolite, Oxan_X the Si/Al ratio was equal to 1.6:1. The silicon and the aluminum are characteristic elements in the structural organization of the aluminosilicate, by the three-dimensional combination of tetrahedron of the type \(\:\text{S}\text{i}{\text{O}}_{4}^{-}\) and \(\:\text{A}\text{l}{\text{O}}_{4}^{-}\) bound together by oxygen atoms (O). In zeolite ZN 2040, the Si/Al ratio is much higher, approximately 6:1. Other metals as iron (Fe), calcium (Ca), potassium (K) e sulfur (S), were detected at lower concentrations, but not less important because they perform functions, within the crystal structure, that contribute decisively on the adsorption of various adsorbents. In the diffractogram of zeolite ZN 2040 the set of peaks at 2Ɵ are characteristic of the Clinoptilolite with traces of Mordernite and the presence of heulandite, strong evidence of a crystalline monoclinic system with orthorhombic traits, characteristic of Mordernite. The synthetic zeolite Oxan_X, displays the characteristic peaks of the faujazite structure (FAU). The samples presented different mass loss behavior. The thermogravimetric curve of zeolite ZN 2040 shows water loss between 25 to 192 ºC, with a peak in 29.46 ºC. It holds thermal stability at temperatures above 650°C. The mass loss observed corresponds to 9.41%. The curve of the synthetic zeolite Oxan_X showed water loss of hydration between the 28.32 ºC to 180 ºC and a subsequent peak around 590 ºC related to zeolitic water. Mass loss of approximately 11.26% was observed. Surface area and porosity were measured by the adsorption and desorption isotherms –with nitrogen gas condensing (N 2 ). The Table (1) shows the specific physical properties by the BET multi point method in the range between 0.033 and 0.305 P/P 0 . Table 1 Physical properties of the adsorbents tested. Specific Surface Area Porosity Adsorbents Multi Point BET (m²/g) Specific Zeolite Weight (g/cm³) Pores Total Volume (cm 3 /g) Average Diameter (Å) Pores Size (Å) Micropore volume < 200 (Å) (cm³/g) DFT (Monte Carlo) – Pores Volume (cm³/g) Natural ZN 2040 59.535 2.1044 0.0683 (< 315 Å) 48.0 21.1 0.0612 0.068 Synthetic Oxan_X 506.638 2.2429 0.3102 (< 304.7Å) 23.6 104.9 0.2989 0.310 The synthetic zeolite Oxan_X showed a higher total pore volume and, consequently, higher micropore volume. The results show the relationship between the existences of the higher volume of microspores with the specific surface area. Measurements of specific weight were conducted by picnometer technique with water, wherein the synthetic zeolite Oxan_X showed slightly higher specific weight of (2.2429 ± 0.0016 g/cm³), and the natural zeolite ZN 2040 showed lower specific weight (2.1044 ± 0.0001 g/cm³). 3.2. Vehicle emissions of greenhouse effect gases Figures (4) and (5) present the results of CO 2 emissions added to CO emissions, because both can cause greenhouse effect, one as a direct agent and the other as a precursory agent. The use of natural zeolite ZN 2040 provided a reduction in the emissions of those gases of approximately 24.97%, considering the combined cycle (55% urban and 45% roadway), 20.96% and 32.60% in urban and roadway separate cycles, respectively, using ethanol fuel. With the synthetic zeolite Oxan_X, the emission reductions are around 15.62% in combined cycle, and 14.39% and 17.46% in urban and roadway cycle, respectively, with Ethanol, Figure (4a). Operating with Gasoline 22% AEAC, the zeolite ZN 2040 reduced, around, 8.03% of CO 2 + CO, only in the road route, in the urban route there is an increase in emissions, around, 23.43%, as a consequence, the results in the combined route presents an increase of emissions of greenhouse effect and precursor gases, around 12.57%. On the other hand, with the application of synthetic zeolite Oxan_X there were reductions of 12.83% in urban cycle, 29.31% in roadways and 17.18% in combined cycle, as it is shown in the Figure (4b). The results can be shown as well, in combined cycle route (55% urban and 45% roadway) with ethanol, gasoline and 22% AEAC and combined fueling (55% Ethanol and 45% Gasoline 22% AEAC, in volume), as shown in the Fig. 5. With the fixed bed column packed with natural zeolite ZN 2040, in the combination of CO 2 + CO with ethanol, it occurs a reduction in the emission of greenhouse effect gases of 28.57%, and an increase in these emissions of 6.50%, with Gasoline 22% AEAC. With the synthetic zeolite Oxan_X there is a reduction of 16.15% with Ethanol 21.32% with Gasoline 22% AEAC. Considering the vehicle is fueled with 55% ethanol, 45% gasoline and 22% AEAC, with natural zeolite ZN 2040 there is a reduction in CO 2 + CO emissions of 20.01% and reduction of 18.13% with synthetic zeolite Oxan_X. The results show that the use of flow fixed bed column filled up with synthetic zeolite Oxan_X, presents a better performance in reducing the emissions of CO 2 and greenhouse effect precursor gases, released by automotive vehicles of Otto cycle, which operate on ethanol or gasoline 22% AEAC. The results of carbon dioxide (CO 2 ) and carbon monoxide (CO), on a molar basis (mols/L) are shown in Figures (6a) and (6b). When using Ethanol there was reduction but, fueled with Gasoline 22% AEAC there was no reduction in the substance quantity concentration of CO 2 , using the natural zeolite ZN 2040 in urban and roadway route. With synthetic zeolite, Oxan_X occurs reductions. The results show that using a fixed bed column packed with natural zeolite ZN 2040 it is possible to achieve reductions in CO 2 concentration, around, 4.23% in an urban route, 3.48% in roadway route and 3.88% in combined route, with ethanol fuel. When using synthetic zeolite Oxan_X with Ethanol the reductions were 1.75% in urban cycle, 4.39% in roadways and 2.90% in the combined route, on a molar basis. With gasoline 22% AEAC and column with the zeolite Oxan_X in urban route, there was no reduction, but in the roadway, there was a reduction of 4.37%, and in combined route a reduction of 1.89%. The presence of column with less porous surface features and apparent density lower, cause a transient regime of operation of the motor with slight loss of load in vehicle exhaust. In addition to factors such as: average temperature increase of exhaust and catalytic converter that requires greater raw fuel spray for your cooling, increasing the presence of CO and hydrocarbons; oxidation of the combustion gases, also at high temperatures in the exhaust, in face of the exposure time by the loss of load; CO and CO 2 from the oxidation of unburnt hydrocarbons and; excess CO caused by possible incomplete combustion on chamber. These factors alone or by a combination between them, caused by the presence of the column in the exhaust system, with the structural characteristics of zeolite ZN 2040, associated with the largest concentration of CO and CO 2 , by the burning of gasoline, contributes to the increase of CO 2 in the urban cycle, when using zeolite ZN 2040. Material with less surface area, low total volume of pores and small pore size, when compared to synthetic zeolite Oxan_X. The reductions of emissions, on a molar basis, of (CO 2 ) with the fixed bed column packed with the synthetic zeolite Oxan_X are better, on average, 4.10%, when compared to the results of the natural zeolite ZN 2040. It is a reasonable result, considering that the physical characteristics of the synthetic zeolite Oxan_X present structure with surface area, total pore volume, presence of macro pores and micro pores and pores width greater than the natural zeolite ZN 2040. In addition to chemical and structural characteristics such as: abundant presence of the chemical element aluminum (Al), a trivalent entity, whose tetrahedral of AlO 4 − type, besides inducing negative charges in the structure that promote both acidity and basicity character in their structural sites. 3.3. CO 2 e CO Emissions projection With data from National Federation of Automotive Vehicle Distribution (FENABRAVE, 2013), vehicles with engine size between 1.4 L and 2.0 L, licensed every year in Brazil, around 2.154.945 vehicles, it is possible to estimate the emissions of CO 2 by vehicles in this engine class. Extending the projections of light vehicles licensed from 2015 until the year 2035, Tables (2) and (5) show CO 2 emissions by vehicles with engine size 1.4 L to 2.0 L, operating with Ethanol and Gasoline 22% AEAC, in a time line on the combined cycle, 55% urban and 45% roadway. Considering the number of license plates without engine and vehicle class discrimination, the forecast can reach approximately 5800000 vehicle units in licensed per year in Brazil, according to FENABRAVE (Nacional Federation of Automotive Vehicle Distributors). Table 2 CO 2 emissions accumulated until the year 2035 for vehicles with engine size 1.4 L to 2.0 L, operating with Ethanol in combined cycle. Column/Adsorbent Temporal Emission of CO 2 (Gg) - Ethanol 2015 2020 2025 2030 2035 Reference 6830 23907 40983 58059 75135 Natural ZN 2040 6717 23510 40303 57097 73889 Synthetic Oxan_X 6724 23535 40346 57157 73967 In the projection to the year 2035, vehicles with engine size 1.4 L to 2.0 L fueled with ethanol fuel, using the fixed bed column with the synthetic zeolite Oxan_X, cease to release 1.168 Gg of CO 2 to the environment, and with the zeolite ZN 2040 it ceases to release 1246 Gg. The results show that the performance of zeolite ZN 2040 were slightly better for CO 2 compared to the synthetic zeolite Oxan_X when using ethanol. Table (3) shows the results of CO 2 emissions in the projection until the year 2035, for the vehicles with engine size 1.4 L to 2.0 L fueled with Gasoline 22% AEAC on the combined cycle. Table 3 CO 2 emissions accumulated until the year 2035 by vehicles with engine size 1.4 L to 2.0 L, operating with gasoline 22% AEAC in combined cycle. Column/Adsorbent Temporal Emission of CO 2 (Gg) - Gasoline 2015 2020 2025 2030 2035 Reference 7045 24657 42270 59882 77495 Natural ZN 2040 7095 24833 42571 60309 78046 Synthetic Oxan_X 6976 24414 41853 59292 76731 The results showed that operating with Gasoline 22% AEAC the synthetic zeolite Oxan_X presents a greater performance than the natural zeolite ZN 2040. Thus, by using the column with the synthetic zeolite Oxan_X until 2035, the vehicle in this engine category may cease to release 764 Gg of CO 2 in the environment, considering combined cycle route (55% urban and 45% roadway). The natural zeolite ZN 2040 does not present good performance in the adsorption of CO 2 when the fuel is gasoline 22% AEAC. Still in this same line of thought, the Figures (7a) and (7b) shows the CO emissions, that can be mitigated by the year 2035, by the vehicles with engine size 1.4 L to 2.0 L, operating with Ethanol and Gasoline 22% AEAC in the combined route cycle, using fixed bed columns packed with natural ZN 2040 and synthetic Oxan_X adsorbents. With the use of horizontal flow fixed-bed column, packed with the synthetic zeolite Oxan_X, employed in automotive vehicles with Otto cycle and "Flex Fuel" technology, besides the reduction in greenhouse effect gases of direct action, such as CO 2 , there is also mitigation of precursor gases such as CO in significant amounts in a temporal projection. On average, the levels of CO reduction, in this condition, are 20.50%, with the synthetic zeolite. With the natural zeolite ZN 2040 there was an increase in CO emissions, on average, 5.90% due to urban route condition that does not reduce emissions of this gas with this natural zeolite, when the fuel is gasoline 22% AEAC. 4. CONCLUSIONS The application of horizontal flow fixed-bed column in automotive vehicles with Otto cycle and "Flex Fuel" technology for mitigation of greenhouse effect gases is an effective contributor to the sum of efforts to minimize the effects of global warming, caused by motor vehicles through the burning of fossil fuels. The results show that the capacity of adsorption of CO 2 and precursor greenhouse effect gases, by the adsorbents contained in the fixed bed column are also related, beyond the physical and chemical characteristics of the adsorbent, with the mass amount of adsorbent used in the fixed bed column, because the weight and volume ratio contributes directly to the increase of the surface area and contact of the adsorbate/adsorbent for the mass diffusion of gases on the porous adsorbents. A mass quantity of 2 kg of adsorbents reduced, around, 2% of CO 2 emissions and 17% CO emissions by motor vehicles. Among the zeolites applied, the zeolite that provided greater reduction in vehicle emissions of CO 2 and CO, for both fuels, was the synthetic zeolite Oxan_X, although the natural zeolite has also shown adequate performance in reducing greenhouse effect gases and precursors, under specific conditions. The good performance of zeolite Oxan_X is directly related to the higher volume of micro pores, the higher specific surface area and its selectivity for these gases in view of its crystal and molecular structure. The vehicles could be manufactured in a more efficient way from an energy point of view in order to spend less fuel to travel a given distance. However, improvements in energy efficiency do not necessarily lead to a reduction in energy demand or in emissions of carbon dioxide and other greenhouse effect gases. The reason is that once the equipment is manufactured to reduce energy consumption, the costs required to perform a given task will drop, which will incur in a natural tendency to use the equipment more often because its lower cost operation. Thus, due to the "rebound" effect, the energy saving and the reduction of greenhouse effect gases attributed to improved efficiency in energy consumption would not be achieved in a long-term basis. However, considering technologies that capture these gases added to the efficiency in fuel consumption, it is possible to keep the emissions of CO 2 and of other greenhouse effect gases at controlled and acceptable levels, even with the increase in world energy consumption by the use of automotive transportation. Declarations ACKNOWLEDGMENT The authors acknowledge Fiat SA for providing laboratories, vehicle and measurement instrumentation for the implementation of the tests. They also thanks UFMG for the technical and scientific support, especially the DEMEC, DEMET, INCT - ACQUA and ICex departments. Declaration of interests The author declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. References ABNT (Brazilian Association for Technical Standards). NBR 6601: Veículos rodoviários automotores leves: Determinação de hidrocarbonetos, monóxido de carbono, óxidos de nitrogênio, dióxido de carbono e material particulado no gás de escapamento . Rio de Janeiro, 2005. ABNT (Brazilian Association for Technical Standards). NBR 7024: Veículos rodoviários automotores leves (light Road automotive vehicles): Medição do consumo de combustível (Fuel Consumption measurement) . Rio de Janeiro, 2002. Calero, M., Hernainz, F., Blazquez, G., Tenorio, G., Martin-Lara, M.A. Study of Cr (III) biosorption in a fixed-bed column . J. Hazard. Mater. 171, pp. 886-893, 2009. Crittenden, B., Thomas, W.J. Adsorption technology and design . Elsevier Science and Technology Books, 271p., 1998. France, A. S., Oliveira, L. S., Nunes, A. A., Alves, C. C. O. Microwave assisted thermal treatment of defective coffee beans press cake for the production of adsorbents . Bioresource Technology, v.101, pp. 1068-1074, 2010, ISSN 0960-8524. Science Direct. IPCC. Special Report on Renewable Energy Sources and Climate Change Mitigation . Prepared by Working Group III of the Intergovernmental Panel on Climate Change [O. Edenhofer, R. Pichs-Madruga, Y. Sokona, K. Seyboth, P. Matschoss, S. Kadner, T. Zwickel, P. Eickemeier, G. Hansen, S. Schlömer, C. von Stechow (eds)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 1075p., 2011. IPCC. Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change . Core Writing Team, R.K. Pachauri, and A. Reisinger (eds.), Cambridge University Press, 104p., 2007a. IPCC. Special Report on Emission Scenarios. N. Nakicenovic and R. Swart (eds.), Cambridge University Press, 570p., 2000a. Madia, G. S., Barbieri, G., Drioli, E. Theoretical and experimental analysis of methane steam reforming in a membrane reactor. The Canad. Journal. Chem. Eng., 77, n.4, pp.698-706, 1999. Peck, J. D., Yang, R. T. Effect of binary cross-term diffusivities in molecular sieve on adsorber dynamics . Chem. Eng. Sci., 50, n.21, pp.3487-3491, 1995. Soares, J. L., Oberziner, A. L. B., José, H. J., Rodrigues, A. E., Moreira, R. F. P. M. Carbon Dioxide Adsorption in Brazilian Coals. Energy & Fuels 2007, v.21, pp. 209–215, 2007. Strangeland, A. Why CO 2 Capture and Storage (CCS) is an important strategy to reduce global CO 2 emissions . Bellona Paper. http://www.bellona.no. T Bellona Foundation, Oslo, Norway, 2007. Suzuki, M. Adsorption Engineering . 1 ed., Amsterdam: Elsevier, 1990. Yong, Z., Mata, V., Rodrigues, A. E. Adsorption of Carbon Dioxide Onto Hydrotalcite-Like Compounds (Htlcs) at High Temperatures . Ind. Eng. Chem. Res., 4, 204p., 2001. Weber Jr., W. J., Smith, E.H. Simulation and design models for adsorption processes . Environ. Sci. Technol. 21, pp.1040- 1050, 1987. Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5798522","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":402000770,"identity":"233dd270-a313-4f5f-8b5c-67b46b0e72de","order_by":0,"name":"Theles Costa","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA7klEQVRIiWNgGAWjYDACCQbGA3DOByBmYyegg0eCgQGqhZmBcQZICzMpWph5IDR+YC/dfODAhz8M8vz85w9+tvm1TZ4PaNuHjzl4bJE5lnBwZhuD4cwZyczSuX23DduAtknO3IbPYTkGh3kbGBIMbjAzSOf23GYEamFj5sWrJf/D4T9/gFrOH2b+bdlz254ILTkMhxnYgFoOJLNJM/y4nUhYy400g4O9bRIgv5hZ9jbcTm5jZmzG6xf2GckPH/z4YwMMsYOPb/z4c9t2fnvzwQ8f8WiBAgkIxdgGJhsIqkcCf0hRPApGwSgYBSMFAABs300P9qKg2wAAAABJRU5ErkJggg==","orcid":"","institution":"Universidade Federal de Minas Gerais","correspondingAuthor":true,"prefix":"","firstName":"Theles","middleName":"","lastName":"Costa","suffix":""}],"badges":[],"createdAt":"2025-01-09 17:53:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5798522/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5798522/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":73948514,"identity":"dd208fd4-42ee-4dbf-8f3d-cfb5cf3edde5","added_by":"auto","created_at":"2025-01-16 09:09:24","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":39657,"visible":true,"origin":"","legend":"\u003cp\u003eFull car exhaust system.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5798522/v1/024c5d4644e3bb38d6679799.png"},{"id":73948515,"identity":"e9b5c723-fcaa-40e2-a238-8522f18d954b","added_by":"auto","created_at":"2025-01-16 09:09:24","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":249328,"visible":true,"origin":"","legend":"\u003cp\u003eChassis dynamometer scheme, gas analyzer and gas sampler in Emissions Laboratory.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5798522/v1/d1dc7d9ba18c6b2aafc43433.png"},{"id":73948564,"identity":"2b34cb35-9855-4df5-9e5c-e98a670b93d6","added_by":"auto","created_at":"2025-01-16 09:09:26","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":1846771,"visible":true,"origin":"","legend":"\u003cp\u003eEmission testing in Chassis Dynamometer.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5798522/v1/b7463bb7aa2d9e6f94ee7bc0.png"},{"id":73948571,"identity":"10e8f61c-05dd-4801-8723-3b92c81bb53e","added_by":"auto","created_at":"2025-01-16 09:09:27","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":956805,"visible":true,"origin":"","legend":"\u003cp\u003ea. Total emission of CO\u003csub\u003e2\u003c/sub\u003e + CO with Ethanol in FTP-75 cycle\u003c/p\u003e\n\u003cp\u003eb. Total emission of CO\u003csub\u003e2\u003c/sub\u003e + CO with Gasoline 22% AEAC in FTP-75 cycle.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-5798522/v1/3c8afc2432d9b5b746304862.png"},{"id":73948511,"identity":"475616e7-4e9e-4113-a030-ac0e268dc397","added_by":"auto","created_at":"2025-01-16 09:09:24","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":454515,"visible":true,"origin":"","legend":"\u003cp\u003eTotal emission of CO\u003csub\u003e2\u003c/sub\u003e + CO in combined cycle route with Ethanol, Gasoline 22% AEAC and combined fueling (55% ethanol and 45% gasoline, in volume).\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-5798522/v1/e8d973e9e0f282666cf2d770.png"},{"id":73948861,"identity":"ed81d227-4c56-4aef-931b-edc1ae353315","added_by":"auto","created_at":"2025-01-16 09:17:28","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":431998,"visible":true,"origin":"","legend":"\u003cp\u003ea. Concentrations of CO\u003csub\u003e2\u003c/sub\u003e with Ethanol, urban and roadway phase of FTP-75 cycle.\u003c/p\u003e\n\u003cp\u003eb. Concentration of CO\u003csub\u003e2\u003c/sub\u003e with Gasoline 22% AEAC, urban and roadway phase of FTP-75 cycle.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-5798522/v1/cba82eef23c7b3cd2fc4a8f9.png"},{"id":73948554,"identity":"fcd7fe55-a6da-401d-8606-bba125330259","added_by":"auto","created_at":"2025-01-16 09:09:25","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":354030,"visible":true,"origin":"","legend":"\u003cp\u003ea. CO emissions accumulated by the year 2035 by vehicles with engine size 1.4 L to 2.0 L, operating with Ethanol.\u003c/p\u003e\n\u003cp\u003eb. CO emissions accumulated by the year 2035 by vehicles with engine size 1.4 L to 2.0 L, operating with Gasoline 22% AEAC (b).\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-5798522/v1/3fcf4beea5e899214261069c.png"},{"id":75836670,"identity":"39fa3dbf-2811-4a46-aa7e-e6fff4464e1f","added_by":"auto","created_at":"2025-02-09 14:46:43","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4928032,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5798522/v1/9ad19b04-b787-4db9-99a2-8b64da58ccc0.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eMethodology Development for Capturing Co2 and Precursor Gases of Greenhouse Effect From the Exhaust of Flex-fuel Internal Combustion Engines\u003c/p\u003e","fulltext":[{"header":"1. INTRODUCTION","content":"\u003cp\u003eClimate changes predicted for the 21st century and the subsequent ones do not present exciting prospects. According to the projections of the Intergovernmental Panel on Climate Change (IPCC), a group funded by the United Nations Environmental Plan, if no further action is taken to reduce emissions of CO\u003csub\u003e2\u003c/sub\u003e and other greenhouse effect gases; around the year of 2035, the average air temperature will be 1\u0026deg;C higher than it was in 1990. In the year of 2100, it will increase more than 2\u0026deg;C (IPCC, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2000a\u003c/span\u003e and 2011).\u003c/p\u003e \u003cp\u003eThere are numerous technical and scientific arguments built through experiments and empirical methodological resources, which illustrate the current and modern ways to reduce greenhouse effect gas emissions by proposals of capture and adsorption of carbon dioxide and precursor gases from emissions gases in flows launched to the atmosphere by anthropogenic action, mainly through the burning of fossil fuels. There are many techniques that can be used in the separation of CO\u003csub\u003e2\u003c/sub\u003e from fuel gas streams, and the adsorption is the most widely used commercial operation (Yong, Mata, Rodrigues, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2001\u003c/span\u003e; Madia, Barbieri, Drioli, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e1999\u003c/span\u003e). The carbon capture and storage (CCS) is the technology with the greatest potential to reduce CO\u003csub\u003e2\u003c/sub\u003e emissions on a large scale in the next 20 years (Strangeland, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). Economic growth in this period will not allow abandoning fossil fuels, but it should be considered the adoption of three bases: increasing of the energy efficiency of manufacturing processes, enhanced participation of renewable energy in the energy matrix and promotion of the widespread application of CCS (Carbon Capture and Storage).\u003c/p\u003e \u003cp\u003eMuch of the currently used processes for the adsorptive separation is based on the balance, using synthetic zeolites, 5A and 13X as adsorbents. In contrast, carbon molecular sieve (CMS) and 4A zeolites can separate the air based on their kinetic selectivity (Peck and Yang, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e1995\u003c/span\u003e). Soares et al. (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2007\u003c/span\u003e) investigated the equilibrium kinetics of CO\u003csub\u003e2\u003c/sub\u003e adsorption in Brazilian coal at low pressures. The adsorption capacity was in the range of 0.089\u0026ndash;0.186 mmol CO\u003csub\u003e2\u003c/sub\u003e/g, typical values for coal with high ash content. The adsorption in a fixed bed column containing the granular carbon (0.8, 2.4 and 4.8 mm) showed that the rate of adsorption is fast and a mathematical model describing the dynamics of CO\u003csub\u003e2\u003c/sub\u003e adsorption on a fixed bed column was developed (Soares et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2007\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe most important industrial processes of gaseous stream adsorption are associated with the adsorption in one column. Adsorbent particles are accommodated in a column and a gaseous stream containing one or more adsorbates flows through the bed (Suzuki, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e1990\u003c/span\u003e; France et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). When the volume of the fluid begins to flow through the column, the mass transfer zone varies from 0\u0026ndash;100% of the inlet concentration (corresponding to full saturation of the adsorbent). From a practical point of view, the saturation time is established when the adsorbed concentration in the effluent reaches 90 to 95% of the inlet concentration (Calero et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). The flux of a component of a control volume inwards or outward can include a large amount flux, with dispersion flux and molecular diffusion (Weber Jr. and Smith, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e1987\u003c/span\u003e). The resultant differential equations that represent the variation of adsorbate concentration in both, fluid and solid phases using an equation of state can be adapted to a gaseous supply (Crittenden and Thomas, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e1998\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIt is unclear how the carbon dioxide and the greenhouse effect precursor gases could be removed from car exhaust gases and other less centralized sources, but collectively important; perhaps this goal could be achieved indirectly by the use of hydrogen or electricity as an energy source, which could be produced from carbonaceous fuels, in a plant, in which \u003cem\u003eCO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e and precursor gases could be collected efficiently or, as suggested by this paper by adsorption directly in vehicular exhaust duct.\u003c/p\u003e \u003cp\u003eThe objective of this work is to develop an appropriate methodology to alleviate the emission of carbon dioxide and greenhouse effect precursor gases by the selective capture of this gas in the exhaust gaseous streams from internal combustion engines. Therefore, it means specifically to propose an innovative system for reducing emissions of greenhouse effect gases released by internal combustion engines, and evaluate the efficiency of solid commercial adsorbents, for these gases released by vehicles operating on Gasoline 22% Anhydrous Ethyl Alcohol Fuel (AEAC) and hydrated Ethanol.\u003c/p\u003e"},{"header":"2. Material and Methods","content":"\u003cp\u003eIn thermal engines, the amount of air is an essential factor in gases emissions, because by ranging the amount of air in the mixture of air/fuel an incomplete combustion may occur causing high concentrations of pollutants and greenhouse effect precursory gases in exhaustion. On the other hand, the complete burning of this fuel will inevitable produce amounts of CO\u003csub\u003e2\u003c/sub\u003e, a major greenhouse effect gas.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1. Infrastructure\u003c/h2\u003e \u003cp\u003eThe tests were performed in a commercial production vehicle, Fiat Idea, Attractive version, 1.4 8V EVO Flex Fuel, 5 doors, kindly yielded by Fiat Chrysler Automobiles, with flicker ignition combustion engine of Otto cycle, 4 cylinders in line, transverse position, powered by gasoline or hydrated ethanol. With the aid of an experimental device for the measurement and analysis of vehicle emissions, before the installation of adsorption column in the vehicles exhaust system.\u003c/p\u003e \u003cdiv id=\"Sec4\" class=\"Section3\"\u003e \u003ch2\u003e2.1.1. Vehicle's exhaust system\u003c/h2\u003e \u003cp\u003eThe Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the vehicle exhaust set and its main components. The front noise damper also works as a Fixed Bed Column of Horizontal Flow and its internal part is filled up with the adsorbent material for capture of CO\u003csub\u003e2\u003c/sub\u003e and greenhouse effect precursor gases from other exhaust gases.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe front noise damper, a metallic tube set with internal division called Resonator box which receives, by spraying, the exhaustion gases for final reduction of the noise level, will also serve as exhaust gas filter. The Fixed Bed Column is located at this component of the exhaust line by filling up the rear resonance compartment with adsorbents to retain a portion of vehicle emissions.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.2. The adsorbents used\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe adsorbent used in the fixed bed column of horizontal flow were ZN 2040 natural zeolite Clinoptilolita supplied by Celta Brazil and Oxan_X synthetic zeolite, supplied by Oxanyl Raos. Two different materials with similar adsorption characteristics and singular obtainment ways, one extracted directly from nature and used fresh and a material synthesized in laboratory were also tested.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.3. Adsorbents characterization (zeolites)\u003c/h2\u003e \u003cp\u003eThe characterization of the adsorbent included the semi-quantitative chemical composition by X-ray fluorescence, specific surface area measurement by N\u003csub\u003e2\u003c/sub\u003e Chemisorption, specific weight by Picnometry by water intrusion thermal behavior by TGA (thermogravimetric analysis); DTA (Differential thermal analysis), DSC (Differential scanning calorimetry) and crystalline phases identification by X-ray Diffraction (XRD). The equipment employed in the analysis were: a fluorescence spectrometer for x-ray dispersive Energy, brand SHIMADZU model EDX-720, adsorptometers, Quantachrome instruments, brand NEW model 1000 capacity for a range of 10\u0026thinsp;\u0026minus;\u0026thinsp;8 P/P0 (N\u003csub\u003e2\u003c/sub\u003e/77 K), picnometer of 50 ml; Shimadzu precision scale AY 220 max. 220 g/min. 0.01 g with resolution 0.0001 g. Thermobalance Shimadzu-TGA50H, thermobalance Netzsch -STA409EP, differential calorimeter Shimadzu-DSC50, Analyzer thermomechanical Shimadzu-TMA50, Analyzer DTG-60 simultaneous TG/DTA Shimadzu and an x-ray diffractometer PANalytical EMPYREAN model, equipped with copper anode tube. The analyzes were performed at the Laboratory of Materials and Chemical Analysis of Fiat Chrysler Automobiles, at the Physical Chemistry labs and X-rays of DEMET- Department of Metallurgical and Material Engineering, and in the Institute of Exact Sciences ICEX - Chemistry Department of the Federal University of Minas Gerais - UFMG.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e2.4. Emissions laboratory\u003c/h2\u003e \u003cp\u003eThe determinations of vehicle emissions were held at the Emissions Laboratory of the Innovation and Technology Center SENAI / FIEMG - Campus CETEC, equipped with:\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003eChassis Dynamometer;\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eGases Analyzers;\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eSampling system for constant volume (AVL);\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eDriver-Aid; Fuel storage chamber;\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eFlow calibrator Laminar Flow Element type (LEF);\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eCFO system (Critical Flow Orifice) and,\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eA modern structure with computerized hardware or software that enable the interface and real-time transfer of results.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003eThe Figure (2) illustrates the main modules of the workbench for emission testing with assembly layout and distribution of equipment used for the analysis of vehicle emissions, the concentration of CO\u003csub\u003e2\u003c/sub\u003e and greenhouse effect precursor gases. From the roller dynamometer, through the collection/dilution of emission gases led to the analyzers, finishing with the records of the data analysis.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eSampling of gases was performed by measuring the emissions gases real mass produced in the burning of the fuel that were released by vehicle exhaust. Sampling system with constant volume Pierburg brand CVS-CFV 30wt 3D-model comprising: Venturis of 6, 9 e 12 m\u0026sup3;/min.; Four pair of \u0026ldquo;bags\u0026rdquo;; Heat exchanger system in the duct of the exhaust gases with GWK temperature control unit; Logotherm, Teco WDC 100.18 model; Collection system of the exhaust gases, ambient air filtration and dilution. The total volume of the mixture between exhaust gas/air dilutions was measured, and a part of this volume was continuously collected for analysis. The \"bags\" manufactured with specific material, were responsible for the collection of samples for the dilution air and the diluted gas emissions without changes in composition of the stored samples.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e2.5. Vehicle settings\u003c/h2\u003e \u003cp\u003eThree different configurations were set up, one with the vehicle in its original condition and the other two with the adsorbents filling up the column in the front noise damper. The settings were called: Reference Column, ZN 2040 Column and Oxan_X Column. The steps for the columns preparation were:\u003c/p\u003e \u003cp\u003eStep 1 - Preparation of two cuts (100 x 100mm) in the plate of the damper casing, for filling up the front cavity with the adsorbent, which forms the Fixed Bed Column in this region for adsorption of gases.\u003c/p\u003e \u003cp\u003eStep 2 - To control the weights of the front noise damper before and after filling up with the adsorbent.\u003c/p\u003e \u003cp\u003eStep 3 - The region of the resonator chamber was filled up with the adsorbent. Two kilograms (2.0 kg) for each column. After filling up the column, the cutouts in the external noise damper plate were welded.\u003c/p\u003e \u003cp\u003eStep 4 - After finishing the preparation of the fixed bed column in the rear noise damper, this was replaced in the vehicle for the emission testing. After the assembly, the same testing was carried out with the vehicle at reference conditions, Figure (3).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e2.6. Implementation of emissions testing\u003c/h2\u003e \u003cp\u003eThe tests were performed according to the methods described in the NBR 6601 (ABNT, 2005) and NBR 7024 standards (ABNT, 2002) and simulated a trip of average duration, in urban areas, approximately 17.88 km on an urban cycle, and a trip of 16.40 km on a roadway cycle. The cycle was defined by a continuous chart of speed in function of time, known as the FTP-75 test. The gas collected in the vehicle is diluted in air in order to obtain a constant total flow. Part of this mixture was also collected in constant flow and stored for analysis. The levels of emission were determined by the final sample concentrations and by the mixture total volume during the stages of the cycle.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results and Considerations","content":"\u003cdiv id=\"Sec11\"\u003e\n \u003ch2\u003e3.1. Adsorbents characterization\u003c/h2\u003e\n \u003cp\u003eAs expected, in both samples, the elements silicon (Si) and aluminum (Al) are predominant. In synthetic zeolite, Oxan_X the Si/Al ratio was equal to 1.6:1. The silicon and the aluminum are characteristic elements in the structural organization of the aluminosilicate, by the three-dimensional combination of tetrahedron of the type \\(\\:\\text{S}\\text{i}{\\text{O}}_{4}^{-}\\) and \\(\\:\\text{A}\\text{l}{\\text{O}}_{4}^{-}\\) bound together by oxygen atoms (O). In zeolite ZN 2040, the Si/Al ratio is much higher, approximately 6:1. Other metals as iron (Fe), calcium (Ca), potassium (K) e sulfur (S), were detected at lower concentrations, but not less important because they perform functions, within the crystal structure, that contribute decisively on the adsorption of various adsorbents.\u003c/p\u003e\n \u003cp\u003eIn the diffractogram of zeolite ZN 2040 the set of peaks at 2Ɵ are characteristic of the Clinoptilolite with traces of Mordernite and the presence of heulandite, strong evidence of a crystalline monoclinic system with orthorhombic traits, characteristic of Mordernite. The synthetic zeolite Oxan_X, displays the characteristic peaks of the faujazite structure (FAU).\u003c/p\u003e\n \u003cp\u003eThe samples presented different mass loss behavior. The thermogravimetric curve of zeolite ZN 2040 shows water loss between 25 to 192 ºC, with a peak in 29.46 ºC. It holds thermal stability at temperatures above 650°C. The mass loss observed corresponds to 9.41%. The curve of the synthetic zeolite Oxan_X showed water loss of hydration between the 28.32 ºC to 180 ºC and a subsequent peak around 590 ºC related to zeolitic water. Mass loss of approximately 11.26% was observed.\u003c/p\u003e\n \u003cp\u003eSurface area and porosity were measured by the adsorption and desorption isotherms –with nitrogen gas condensing (N\u003csub\u003e2\u003c/sub\u003e). The Table\u0026nbsp;(1) shows the specific physical properties by the BET multi point method in the range between 0.033 and 0.305 P/P\u003csub\u003e0\u003c/sub\u003e.\u003c/p\u003e\n \u003cdiv\u003e\n \u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv\u003eTable 1\u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003ePhysical properties of the adsorbents tested.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"8\"\u003e \u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\n \u003cp\u003eSpecific Surface Area\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"5\" nameend=\"c8\" namest=\"c4\"\u003e\n \u003cp\u003ePorosity\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eAdsorbents\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eMulti Point BET\u003c/p\u003e\n \u003cp\u003e(m²/g)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003eSpecific Zeolite Weight (g/cm³)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003ePores Total Volume (cm\u003csup\u003e3\u003c/sup\u003e/g)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003eAverage Diameter (Å)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003ePores Size (Å)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003eMicropore volume \u0026lt; 200 (Å) (cm³/g)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c8\"\u003e\n \u003cp\u003eDFT (Monte Carlo) – Pores Volume (cm³/g)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eNatural ZN 2040\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e59.535\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e2.1044\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.0683\u003c/p\u003e\n \u003cp\u003e(\u0026lt; 315 Å)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e48.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e21.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e0.0612\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c8\"\u003e\n \u003cp\u003e0.068\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eSynthetic Oxan_X\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e506.638\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e2.2429\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.3102\u003c/p\u003e\n \u003cp\u003e(\u0026lt; 304.7Å)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e23.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e104.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e0.2989\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c8\"\u003e\n \u003cp\u003e0.310\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003eThe synthetic zeolite Oxan_X showed a higher total pore volume and, consequently, higher micropore volume. The results show the relationship between the existences of the higher volume of microspores with the specific surface area. Measurements of specific weight were conducted by picnometer technique with water, wherein the synthetic zeolite Oxan_X showed slightly higher specific weight of (2.2429 ± 0.0016 g/cm³), and the natural zeolite ZN 2040 showed lower specific weight (2.1044 ± 0.0001 g/cm³).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\"\u003e\n \u003ch2\u003e3.2. Vehicle emissions of greenhouse effect gases\u003c/h2\u003e\n \u003cp\u003eFigures (4) and (5) present the results of CO\u003csub\u003e2\u003c/sub\u003e emissions added to CO emissions, because both can cause greenhouse effect, one as a direct agent and the other as a precursory agent. The use of natural zeolite ZN 2040 provided a reduction in the emissions of those gases of approximately 24.97%, considering the combined cycle (55% urban and 45% roadway), 20.96% and 32.60% in urban and roadway separate cycles, respectively, using ethanol fuel. With the synthetic zeolite Oxan_X, the emission reductions are around 15.62% in combined cycle, and 14.39% and 17.46% in urban and roadway cycle, respectively, with Ethanol, Figure (4a).\u003c/p\u003e\n \u003cp\u003eOperating with Gasoline 22% AEAC, the zeolite ZN 2040 reduced, around, 8.03% of CO\u003csub\u003e2\u003c/sub\u003e + CO, only in the road route, in the urban route there is an increase in emissions, around, 23.43%, as a consequence, the results in the combined route presents an increase of emissions of greenhouse effect and precursor gases, around 12.57%. On the other hand, with the application of synthetic zeolite Oxan_X there were reductions of 12.83% in urban cycle, 29.31% in roadways and 17.18% in combined cycle, as it is shown in the Figure (4b).\u003c/p\u003e\n \u003cp\u003eThe results can be shown as well, in combined cycle route (55% urban and 45% roadway) with ethanol, gasoline and 22% AEAC and combined fueling (55% Ethanol and 45% Gasoline 22% AEAC, in volume), as shown in the Fig.\u0026nbsp;5. With the fixed bed column packed with natural zeolite ZN 2040, in the combination of CO\u003csub\u003e2\u003c/sub\u003e + CO with ethanol, it occurs a reduction in the emission of greenhouse effect gases of 28.57%, and an increase in these emissions of 6.50%, with Gasoline 22% AEAC. With the synthetic zeolite Oxan_X there is a reduction of 16.15% with Ethanol 21.32% with Gasoline 22% AEAC. Considering the vehicle is fueled with 55% ethanol, 45% gasoline and 22% AEAC, with natural zeolite ZN 2040 there is a reduction in CO\u003csub\u003e2\u003c/sub\u003e + CO emissions of 20.01% and reduction of 18.13% with synthetic zeolite Oxan_X.\u003c/p\u003e\n \u003cp\u003eThe results show that the use of flow fixed bed column filled up with synthetic zeolite Oxan_X, presents a better performance in reducing the emissions of CO\u003csub\u003e2\u003c/sub\u003e and greenhouse effect precursor gases, released by automotive vehicles of Otto cycle, which operate on ethanol or gasoline 22% AEAC.\u003c/p\u003e\n \u003cp\u003eThe results of carbon dioxide (CO\u003csub\u003e2\u003c/sub\u003e) and carbon monoxide (CO), on a molar basis (mols/L) are shown in Figures (6a) and (6b). When using Ethanol there was reduction but, fueled with Gasoline 22% AEAC there was no reduction in the substance quantity concentration of CO\u003csub\u003e2\u003c/sub\u003e, using the natural zeolite ZN 2040 in urban and roadway route. With synthetic zeolite, Oxan_X occurs reductions.\u003c/p\u003e\n \u003cp\u003eThe results show that using a fixed bed column packed with natural zeolite ZN 2040 it is possible to achieve reductions in CO\u003csub\u003e2\u003c/sub\u003e concentration, around, 4.23% in an urban route, 3.48% in roadway route and 3.88% in combined route, with ethanol fuel. When using synthetic zeolite Oxan_X with Ethanol the reductions were 1.75% in urban cycle, 4.39% in roadways and 2.90% in the combined route, on a molar basis. With gasoline 22% AEAC and column with the zeolite Oxan_X in urban route, there was no reduction, but in the roadway, there was a reduction of 4.37%, and in combined route a reduction of 1.89%.\u003c/p\u003e\n \u003cp\u003eThe presence of column with less porous surface features and apparent density lower, cause a transient regime of operation of the motor with slight loss of load in vehicle exhaust. In addition to factors such as: average temperature increase of exhaust and catalytic converter that requires greater raw fuel spray for your cooling, increasing the presence of CO and hydrocarbons; oxidation of the combustion gases, also at high temperatures in the exhaust, in face of the exposure time by the loss of load; CO and CO\u003csub\u003e2\u003c/sub\u003e from the oxidation of unburnt hydrocarbons and; excess CO caused by possible incomplete combustion on chamber. These factors alone or by a combination between them, caused by the presence of the column in the exhaust system, with the structural characteristics of zeolite ZN 2040, associated with the largest concentration of CO and CO\u003csub\u003e2\u003c/sub\u003e, by the burning of gasoline, contributes to the increase of CO\u003csub\u003e2\u003c/sub\u003e in the urban cycle, when using zeolite ZN 2040. Material with less surface area, low total volume of pores and small pore size, when compared to synthetic zeolite Oxan_X.\u003c/p\u003e\n \u003cp\u003eThe reductions of emissions, on a molar basis, of (CO\u003csub\u003e2\u003c/sub\u003e) with the fixed bed column packed with the synthetic zeolite Oxan_X are better, on average, 4.10%, when compared to the results of the natural zeolite ZN 2040. It is a reasonable result, considering that the physical characteristics of the synthetic zeolite Oxan_X present structure with surface area, total pore volume, presence of macro pores and micro pores and pores width greater than the natural zeolite ZN 2040. In addition to chemical and structural characteristics such as: abundant presence of the chemical element aluminum (Al), a trivalent entity, whose tetrahedral of AlO\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e−\u003c/sup\u003e type, besides inducing negative charges in the structure that promote both acidity and basicity character in their structural sites.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\"\u003e\n \u003ch2\u003e3.3. CO\u003csub\u003e2\u003c/sub\u003e e CO Emissions projection\u003c/h2\u003e\n \u003cp\u003eWith data from National Federation of Automotive Vehicle Distribution (FENABRAVE, 2013), vehicles with engine size between 1.4 L and 2.0 L, licensed every year in Brazil, around 2.154.945 vehicles, it is possible to estimate the emissions of CO\u003csub\u003e2\u003c/sub\u003e by vehicles in this engine class. Extending the projections of light vehicles licensed from 2015 until the year 2035, Tables\u0026nbsp;(2) and (5) show CO\u003csub\u003e2\u003c/sub\u003e emissions by vehicles with engine size 1.4 L to 2.0 L, operating with Ethanol and Gasoline 22% AEAC, in a time line on the combined cycle, 55% urban and 45% roadway. Considering the number of license plates without engine and vehicle class discrimination, the forecast can reach approximately 5800000 vehicle units in licensed per year in Brazil, according to FENABRAVE (Nacional Federation of Automotive Vehicle Distributors).\u003c/p\u003e\n \u003cdiv\u003e\n \u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv\u003eTable 2\u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eCO\u003csub\u003e2\u003c/sub\u003e emissions accumulated until the year 2035 for vehicles with engine size 1.4 L to 2.0 L, operating with Ethanol in combined cycle.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"6\"\u003e \u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\n \u003cp\u003eColumn/Adsorbent\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e\n \u003cp\u003eTemporal Emission of CO\u003csub\u003e2\u003c/sub\u003e (Gg) - Ethanol\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e2015\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e2020\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e2025\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e2030\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e2035\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eReference\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e6830\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e23907\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e40983\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e58059\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e75135\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eNatural ZN 2040\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e6717\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e23510\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e40303\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e57097\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e73889\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eSynthetic Oxan_X\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e6724\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e23535\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e40346\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e57157\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e73967\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003eIn the projection to the year 2035, vehicles with engine size 1.4 L to 2.0 L fueled with ethanol fuel, using the fixed bed column with the synthetic zeolite Oxan_X, cease to release 1.168 Gg of CO\u003csub\u003e2\u003c/sub\u003e to the environment, and with the zeolite ZN 2040 it ceases to release 1246 Gg. The results show that the performance of zeolite ZN 2040 were slightly better for CO\u003csub\u003e2\u003c/sub\u003e compared to the synthetic zeolite Oxan_X when using ethanol.\u003c/p\u003e\n \u003cp\u003eTable\u0026nbsp;(3) shows the results of CO\u003csub\u003e2\u003c/sub\u003e emissions in the projection until the year 2035, for the vehicles with engine size 1.4 L to 2.0 L fueled with Gasoline 22% AEAC on the combined cycle.\u003c/p\u003e\n \u003cdiv\u003e\n \u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv\u003eTable 3\u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eCO\u003csub\u003e2\u003c/sub\u003e emissions accumulated until the year 2035 by vehicles with engine size 1.4 L to 2.0 L, operating with gasoline 22% AEAC in combined cycle.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"6\"\u003e \u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\n \u003cp\u003eColumn/Adsorbent\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e\n \u003cp\u003eTemporal Emission of \u003cem\u003eCO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e (Gg) - Gasoline\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e2015\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e2020\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e2025\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e2030\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e2035\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eReference\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e7045\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e24657\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e42270\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e59882\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e77495\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eNatural ZN 2040\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e7095\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e24833\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e42571\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e60309\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e78046\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eSynthetic Oxan_X\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e6976\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e24414\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e41853\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e59292\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e76731\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003eThe results showed that operating with Gasoline 22% AEAC the synthetic zeolite Oxan_X presents a greater performance than the natural zeolite ZN 2040. Thus, by using the column with the synthetic zeolite Oxan_X until 2035, the vehicle in this engine category may cease to release 764 Gg of CO\u003csub\u003e2\u003c/sub\u003e in the environment, considering combined cycle route (55% urban and 45% roadway). The natural zeolite ZN 2040 does not present good performance in the adsorption of CO\u003csub\u003e2\u003c/sub\u003e when the fuel is gasoline 22% AEAC.\u003c/p\u003e\n \u003cp\u003eStill in this same line of thought, the Figures (7a) and (7b) shows the CO emissions, that can be mitigated by the year 2035, by the vehicles with engine size 1.4 L to 2.0 L, operating with Ethanol and Gasoline 22% AEAC in the combined route cycle, using fixed bed columns packed with natural ZN 2040 and synthetic Oxan_X adsorbents.\u003c/p\u003e\n \u003cp\u003eWith the use of horizontal flow fixed-bed column, packed with the synthetic zeolite Oxan_X, employed in automotive vehicles with Otto cycle and \"Flex Fuel\" technology, besides the reduction in greenhouse effect gases of direct action, such as CO\u003csub\u003e2\u003c/sub\u003e, there is also mitigation of precursor gases such as CO in significant amounts in a temporal projection. On average, the levels of CO reduction, in this condition, are 20.50%, with the synthetic zeolite. With the natural zeolite ZN 2040 there was an increase in CO emissions, on average, 5.90% due to urban route condition that does not reduce emissions of this gas with this natural zeolite, when the fuel is gasoline 22% AEAC.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"4. CONCLUSIONS","content":"\u003cp\u003eThe application of horizontal flow fixed-bed column in automotive vehicles with Otto cycle and \"Flex Fuel\" technology for mitigation of greenhouse effect gases is an effective contributor to the sum of efforts to minimize the effects of global warming, caused by motor vehicles through the burning of fossil fuels.\u003c/p\u003e \u003cp\u003eThe results show that the capacity of adsorption of CO\u003csub\u003e2\u003c/sub\u003e and precursor greenhouse effect gases, by the adsorbents contained in the fixed bed column are also related, beyond the physical and chemical characteristics of the adsorbent, with the mass amount of adsorbent used in the fixed bed column, because the weight and volume ratio contributes directly to the increase of the surface area and contact of the adsorbate/adsorbent for the mass diffusion of gases on the porous adsorbents. A mass quantity of 2 kg of adsorbents reduced, around, 2% of CO\u003csub\u003e2\u003c/sub\u003e emissions and 17% CO emissions by motor vehicles.\u003c/p\u003e \u003cp\u003eAmong the zeolites applied, the zeolite that provided greater reduction in vehicle emissions of CO\u003csub\u003e2\u003c/sub\u003e and CO, for both fuels, was the synthetic zeolite Oxan_X, although the natural zeolite has also shown adequate performance in reducing greenhouse effect gases and precursors, under specific conditions. The good performance of zeolite Oxan_X is directly related to the higher volume of micro pores, the higher specific surface area and its selectivity for these gases in view of its crystal and molecular structure.\u003c/p\u003e \u003cp\u003eThe vehicles could be manufactured in a more efficient way from an energy point of view in order to spend less fuel to travel a given distance. However, improvements in energy efficiency do not necessarily lead to a reduction in energy demand or in emissions of carbon dioxide and other greenhouse effect gases. The reason is that once the equipment is manufactured to reduce energy consumption, the costs required to perform a given task will drop, which will incur in a natural tendency to use the equipment more often because its lower cost operation. Thus, due to the \"rebound\" effect, the energy saving and the reduction of greenhouse effect gases attributed to improved efficiency in energy consumption would not be achieved in a long-term basis. However, considering technologies that capture these gases added to the efficiency in fuel consumption, it is possible to keep the emissions of CO\u003csub\u003e2\u003c/sub\u003e and of other greenhouse effect gases at controlled and acceptable levels, even with the increase in world energy consumption by the use of automotive transportation.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eACKNOWLEDGMENT\u003c/p\u003e\n\u003cp\u003eThe authors acknowledge Fiat SA for providing laboratories, vehicle and measurement instrumentation for the implementation of the tests. They also thanks UFMG for the technical and scientific support, especially the DEMEC, DEMET, INCT - ACQUA and ICex departments.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDeclaration of interests\u003c/strong\u003e\u003c/p\u003e\n\n\u003cp\u003eThe author declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e\n"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eABNT (Brazilian Association for Technical Standards). \u003cem\u003eNBR 6601: Ve\u0026iacute;culos rodovi\u0026aacute;rios automotores leves: Determina\u0026ccedil;\u0026atilde;o de hidrocarbonetos, mon\u0026oacute;xido de carbono, \u0026oacute;xidos de nitrog\u0026ecirc;nio, di\u0026oacute;xido de carbono e material particulado no g\u0026aacute;s de escapamento\u003c/em\u003e. Rio de Janeiro, 2005.\u003c/li\u003e\n\u003cli\u003eABNT (Brazilian Association for Technical Standards). \u003cem\u003eNBR 7024: Ve\u0026iacute;culos rodovi\u0026aacute;rios automotores leves (light Road automotive vehicles): Medi\u0026ccedil;\u0026atilde;o do consumo de combust\u0026iacute;vel (Fuel Consumption measurement)\u003c/em\u003e. Rio de Janeiro, 2002.\u003c/li\u003e\n\u003cli\u003eCalero, M., Hernainz, F., Blazquez, G., Tenorio, G., Martin-Lara, M.A. \u003cem\u003eStudy of Cr (III) biosorption in a fixed-bed column\u003c/em\u003e. J. Hazard. Mater. 171, pp. 886-893, 2009.\u003c/li\u003e\n\u003cli\u003eCrittenden, B., Thomas, W.J. \u003cem\u003eAdsorption technology and design\u003c/em\u003e. Elsevier Science and Technology Books, 271p., 1998.\u003c/li\u003e\n\u003cli\u003eFrance, A. S., Oliveira, L. S., Nunes, A. A., Alves, C. C. O. \u003cem\u003eMicrowave assisted thermal treatment of defective coffee beans press cake for the production of adsorbents\u003c/em\u003e. Bioresource Technology, v.101, pp. 1068-1074, 2010, ISSN 0960-8524. Science Direct.\u003c/li\u003e\n\u003cli\u003eIPCC. \u003cem\u003eSpecial Report on Renewable Energy Sources and Climate Change Mitigation\u003c/em\u003e. Prepared by Working Group III of the Intergovernmental Panel on Climate Change [O. Edenhofer, R. Pichs-Madruga, Y. Sokona, K. Seyboth, P. Matschoss, S. Kadner, T. Zwickel, P. Eickemeier, G. Hansen, S. Schl\u0026ouml;mer, C. von Stechow (eds)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 1075p., 2011.\u003c/li\u003e\n\u003cli\u003eIPCC. \u003cem\u003eClimate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change\u003c/em\u003e.\u003cem\u003e \u003c/em\u003eCore Writing Team, R.K. Pachauri, and A. Reisinger\u003cem\u003e \u003c/em\u003e(eds.), Cambridge University Press, 104p., 2007a.\u003c/li\u003e\n\u003cli\u003eIPCC. \u003cem\u003eSpecial Report on Emission Scenarios. \u003c/em\u003eN. Nakicenovic and R. Swart (eds.), Cambridge University Press, 570p., 2000a.\u003c/li\u003e\n\u003cli\u003eMadia, G. S., Barbieri, G., Drioli, E. Theoretical and experimental analysis of methane steam reforming in a membrane reactor. The Canad. Journal. Chem. Eng., 77, n.4, pp.698-706, 1999.\u003c/li\u003e\n\u003cli\u003ePeck, J. D., Yang, R. T. \u003cem\u003eEffect of binary cross-term diffusivities in molecular sieve on adsorber dynamics\u003c/em\u003e. Chem. Eng. Sci.,\u003cem\u003e \u003c/em\u003e50, n.21, pp.3487-3491, 1995.\u003c/li\u003e\n\u003cli\u003eSoares, J. L., Oberziner, A. L. B., Jos\u0026eacute;, H. J., Rodrigues, A. E., Moreira, R. F. P. M. \u003cem\u003eCarbon Dioxide Adsorption in Brazilian Coals.\u003c/em\u003e Energy \u0026amp; Fuels 2007, v.21, pp. 209\u0026ndash;215, 2007.\u003c/li\u003e\n\u003cli\u003eStrangeland, A. \u003cem\u003eWhy CO\u003csub\u003e2\u003c/sub\u003e Capture and Storage (CCS) is an important strategy to reduce global CO\u003csub\u003e2\u003c/sub\u003e emissions\u003c/em\u003e. Bellona Paper. http://www.bellona.no. T Bellona Foundation, Oslo, Norway, 2007.\u003c/li\u003e\n\u003cli\u003eSuzuki, M. \u003cem\u003eAdsorption Engineering\u003c/em\u003e. 1 ed., Amsterdam: Elsevier, 1990.\u003c/li\u003e\n\u003cli\u003eYong, Z., Mata, V., Rodrigues, A. E. \u003cem\u003eAdsorption of Carbon Dioxide Onto Hydrotalcite-Like Compounds (Htlcs) at High Temperatures\u003c/em\u003e. Ind. Eng. Chem. Res., 4, 204p., 2001.\u003c/li\u003e\n\u003cli\u003eWeber Jr., W. J., Smith, E.H. \u003cem\u003eSimulation and design models for adsorption processes\u003c/em\u003e. Environ. Sci. Technol. 21, pp.1040- 1050, 1987.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Adsorption, Combustion Engine, Emissions, Dioxide Carbon, Greenhouse Effect, Zeolites","lastPublishedDoi":"10.21203/rs.3.rs-5798522/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5798522/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eDerived largely from the combustion of fuels used in automotive vehicles, CO\u003csub\u003e2\u003c/sub\u003e and precursor gases of greenhouse effect are important emission gases and deserve attention. This paper proposes a method to remove these gases by adsorption, through the capture and separation in exhaustion of vehicles with flex-fuel technology. The technique is feasible because it is based on the solid adsorption capacity and selectivity for CO\u003csub\u003e2\u003c/sub\u003e and precursor gases. The characterization of the used adsorbents, natural ZN2040 and synthetic Oxan_X, show unique characteristics, especially the surface area, adsorption at low pressures, stability to wet gases, application at high temperature, high Si/Al ratio in the crystal structure and the presence of elements such as Fe, Ca, K and S. The adsorbents were arranged in a horizontal fixed bed column, installed in the front vehicle noise muffler of the exhaust system. The Oxan_X synthetic zeolite with improved performance, showed reductions in average of 2,20% of CO\u003csub\u003e2\u003c/sub\u003e about 17% on the precursor gases, mainly CO, both for Gasoline 22% EAAF (Ethyl Alcohol Anhydrous Fuel) and ethanol burning. In addition, it allowed the reduction of other vehicle pollutants. In the long term, the use of vehicular fixed bed column contributes to a reduction of approximately 764000 tons of CO\u003csub\u003e2\u003c/sub\u003e and 23300 t of CO when the vehicle is operating with Gasoline, and 1168000 tons of CO\u003csub\u003e2\u003c/sub\u003e and 18000 t of CO when it is operating with Ethanol. Considering the vehicles of motorization 1.4 L to 2.0 L, and employing 2.0 kg of adsorbent.\u003c/p\u003e","manuscriptTitle":"Methodology Development for Capturing Co2 and Precursor Gases of Greenhouse Effect From the Exhaust of Flex-fuel Internal Combustion Engines","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-01-16 09:08:23","doi":"10.21203/rs.3.rs-5798522/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7475f82d-364b-4041-8c8b-d5dec843d62d","owner":[],"postedDate":"January 16th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-02-09T14:38:34+00:00","versionOfRecord":[],"versionCreatedAt":"2025-01-16 09:08:23","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5798522","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5798522","identity":"rs-5798522","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}