Destruction of 2,4-dichlorophenol vapor in a process involving the combined action of DBD in oxygen and a catalyst

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А. Lapshova, N. E. Gordina, E. Yu. Kvitkova, T. V. Izvekova, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3850529/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 17 Mar, 2024 Read the published version in Plasma Chemistry and Plasma Processing → Version 1 posted 7 You are reading this latest preprint version Abstract In this work, the process of decomposition of 2,4-dichlorophenol (2,4-DCP) vapor under the influence of atmospheric pressure DBD in oxygen was studied. The studies were carried out in two modes: with a catalyst (natural vermiculite doped with zirconium) and without it. A number of basic characteristics of the catalyst were assessed. The rates and effective rate constants of sorption processes, as well as decomposition processes in plasma and plasma-catalytic systems, were determined. Based on these data, the energy efficiency of the decomposition process was calculated. The data obtained suggested that the initial stage of decomposition is the reaction of interaction of electrons with pollutant molecules. The catalyst has been shown to speed up the decomposition process, increase energy efficiency and the conversion of 2,4-DCP to CO 2 molecules, and prevent the formation of condensed products on the reactor walls. The work estimates the carbon and chlorine balances before and after treatment, which reach a maximum of 99 and 60%, respectively. It was also shown that the catalyst retains its activity for at least 7 hours of continuous operation. 2 4-dichlorophenol destruction dielectric barrier discharge catalyst Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction 2,4 dichlorophenol (2,4-DCP) belongs to a group of VOCs (volatile organic compounds) that are ubiquitous [ 1 – 6 ]. A peculiarity of 2,4-DCP (as well as other organochlorine compounds) is that it concentrates when moving along trophic chains [ 7 ]. The main methods for suppressing emissions and discharges of such compounds into the environment involve the use of thermal methods [ 8 , 9 ]. However, in this case, complete neutralization requires the use of high temperatures (more than 1200 degrees C) and long combustion times to prevent the formation of more dangerous compounds such as dioxins [ 10 , 11 ]. For this reason, methods based on the use of plasma of various types of gas discharges for VOC removal are attracting increased interest from researchers [ 12 – 18 ]. Previously [ 17 ] it was studied the decomposition of 2,4-DCP vapor in an atmospheric pressure barrier discharge in oxygen. The process showed quite high efficiency (the degree of decomposition of 2,4-DCP reached 90%). But a drawback was also identified. During operation, a polymer film formed on the inner surface of the reactor and the process performance deteriorated. To eliminate this phenomenon and improve efficiency, in this study we tried a process in which a catalyst was introduced into the plasma zone, because among various VOC elimination strategies, catalytic oxidation is considered one of the most promising technologies for the complete oxidation of VOCs from municipal and industrial waste streams [ 19 – 26 ]. Materials and methods Description of the Experimental Setup The experimental setup is shown in Fig. 1 . This is a cylindrical reactor with an internal diameter of 22 mm made of Pyrex glass, which is a dielectric barrier. An external electrode made of aluminum foil was located outside the glass tube. The internal electrode was an aluminum rod with a diameter of 16 mm. The length of the discharge zone was 8 cm. A catalyst weighing 1 g was located in the gap between the inner electrode and the inner wall of the Pyrex tube. The catalyst was fixed with Teflon perforated washers placed on the internal electrode. To excite the discharge, an alternating voltage source (1000 Hz) was used, which provided an amplitude voltage of up to 60 kV. The voltage drop across the discharge was measured using a high-voltage probe (2000:1). To determine the discharge current, the voltage drop across a 100 Ohm resistance connected in series with the reactor power circuit was measured. A two-channel digital oscilloscope GW Instek GDS-2072 (Instek, Taiwan) was used for measurements. The rms voltage varied in the range of (8–10) kV. In this case, the root mean square value of the current varied from 0.2 to 1.0 mA. The power introduced into the discharge was calculated by numerical integration over the period of the product of current and voltage. The plasma-forming gas was technical oxygen (99.8%), which was supplied to the discharge device using a gas flow former Khromatek-Kristall FGP (Russia) with a volumetric flow rate of 1–3 cm 3 /s. The concentration of 2,4 DCP was set by the temperature of the cell through which the oxygen flow passed. The range of concentration changes was 0.01-1 g/m 3 . To analyze the products, the gas leaving the reactor was passed through an absorption vessel containing ethanol. Analysis methods To quantitatively determine the content of 2,4-DCP at the inlet and outlet of the discharge device, the gas chromatography method (chromatograph Khromatek Kristall-5000, Russia) with an electron capture detector (carrier gas - nitrogen) was used. The chromatograph was preliminarily calibrated using a series of standard solutions of 2,4-DCP in ethanol. The concentration of carbon dioxide was also determined chromatographically using a methanator and a flame ionization detector. The gaseous chlorine formed during the decomposition of 2,4-DCP was absorbed by water, and then active chlorine was determined by the titrimetric method, based on the fact that free chlorine, hypochlorous acid, hypochlorite ion, mono- and dichloramines in an acidic environment react with potassium iodide to release iodine, which was titrated with sodium thiosulfate in the presence of starch [ 27 ]. The probable degradation products of 2,4-DCP were determined by gas chromatography-mass spectral method (GCMS-QP2010Ultra, Shimadzu Europa GMBH). Toluene and n-hexane were used as extractants in sample preparation. Calculated parameters Residence time of the gas in the reactor, calculated as τ R = L⋅S/Q, s − 1 (1) where L is the length of the discharge zone ( L = 8 cm), S is the area of the annular gap of the reactor (S = 1.79 cm 2 ) was 4–14 s, Q is volumetric gas flow (l/s). The degree of decomposition (α) of 2,4-DCP was calculated from the relationship: \(\alpha =\frac{{C}_{in}-{C}_{out}}{{C}_{in}}\times 100\) , % (2) where C in is the concentration of 2,4-DCP at the inlet to the reactor, C out is the concentration of 2,4-DCP at the outlet of the reactor. Kinetic dependences (dependence of concentration on gas residence time) were processed under the assumption that decomposition occurs irreversibly in a reaction of the first kinetic order in the concentration of 2,4-DCP. For this case, the kinetic equation has the form [ 28 ]: \({C}_{out}={C}_{in}\times \text{e}\text{x}\text{p}(-{K}_{D}\times {\tau }_{R})\) , mg m −3 (3) where K D is the effective decomposition rate constant, τ R is the residence time. Eq. (3) describes the experimental data quite well (coefficient of determination R 2 > 0.97). Based on the kinetic data, we also calculated energy efficiency of decomposition φ (the number of decayed molecules per 100 eV of energy input) and the rate of decomposition process W. Since the values of φ and W depend on the contact time, φ and W were determined for the time τ R → 0. The ratios used for the calculation were as follows: \(\phi =\frac{W({\tau }_{R}=0)\times {V}_{R}\times 1.6\times {10}^{-19}\times 100}{P}\) , molecules per 100 eV (4) W(τ R = 0) = K D ×C in (5) where V R – volume of plasma zone (mL 3 ), W – decomposition rate (mL − 3 s − 1 ), 1.6 ×10 − 19 charge of an electron (C), P – the inputted power (W). Based on the measured concentrations of destruction products, the balance of carbon and chlorine was also assessed. For this we used the ratio: $$\delta =\frac{{Y}_{P}}{Y}$$ 6 where Y P is the content of the corresponding element in the product, and Y is the content of the same element in decomposed 2,4-DCP. Characterization of the Catalyst The starting material for preparing the catalyst was natural vermiculite from the Kovdor (Russia) deposit. The size of vermiculite grains was up to 0.6 mm. The chemical composition corresponded to: SiO 2 (37.2%), Al 2 O 3 (6.2%), CaO (15.3%), Fe 2 O 3 (19%), MgO (13.1%). To improve the catalytic properties, the catalyst contained zirconium oxide. To obtain it, zirconium oxychloride octahydrate ZrOCl 2 ∙8H 2 O (CAS No. 13520–92–8) was added to the original vermiculite. The amount of salt was such that the zirconium content was 5 weights percent. The resulting mixture was activated mechanochemically. After this, granules with a diameter of 3 mm were molded from the activated mass and subjected to thermal firing. The catalyst preparation procedure is described in more detail in [ 29 ]. The resulting catalyst had a specific surface area of 15.1±0.8 m 2 /g and a pore volume of 0.023±0.001 cm 3 /g. These values were calculated based on measurements of nitrogen adsorption-desorption isotherms at 77 K using the BET theory. Also, the resulting catalyst turned out to be a good sorbent for 2,4-DCP (Fig. 2 ). From the obtained dependence one can obtain some formal characteristics of adsorption. Let us assume that adsorption occurs on active surface centers of the same type. Then, approximately, we can write the following kinetic equations $$\frac{d{C}_{g}}{dt}=-{K}_{A}\times {C}_{g}\times {C}_{S}$$ 6 $$\frac{d{C}_{s}}{dt}=-{K}_{A}\times {C}_{g}\times {C}_{g}$$ 7 where C g is the concentration in the gas phase, C s is the concentration of active centers on the surface, K A is the effective adsorption rate constant. The solution to the system of Eq. ( 6 ) and Eq. ( 7 ) with the initial conditions C g =C g 0 and C s =C s 0 at t = 0 has the form: $${C}_{g}\left(t\right)=\frac{{C}_{g}^{0}-{C}_{s}^{0}}{1-\frac{{C}_{s}^{0}}{{C}_{g}^{0}}\times \text{e}\text{x}\text{p}[-{K}_{A}\times ({C}_{g}^{0}-{C}_{s}^{0})\times t]}$$ 8 Eq. ( 8 ) describes the experimental dependence very well (Fig. 2 ). The coefficient of determination is R 2 = 0.999. Processing the adsorption curve gives the following parameter values: C g 0 -C s 0 = (14.7±1.7) mg/m 3 , C s 0 / C g 0 =0.88±0.01, K A ×( C g 0 -C s 0 ) = 0.06±0.02 min − 1 or (1±0.3) ×10 − 3 s − 1 . These quantities give the following values: C g =123±15 mg/m 3 (experiment − 125 mg/m 3 ), C s 0 = 108 mg/m 3 , K A =0.0041 m 3 /(mg×min) or 1.1×10 4 l/(mol×s). In order to avoid the influence of absorption on the kinetics of plasma destruction, in all experiments the catalyst was saturated with 2,4-DCP before ignition of the discharge. Results and Discussion Figure 3 shows the kinetics of the decomposition of 2,4-DCP at various initial concentrations in the presence of a catalyst and without it. As already noted, the kinetics of decomposition is well described by a formal first-order law for the concentration of 2,4-DCP (R 2 > 0.97). The effective rate constants ( K eff ), degradation rates, and energy yields of decomposition found from these data are presented in Table 1 . It can be seen that at a constant discharge power, the effective rate constants, within the measurement error, do not depend on the initial concentration of 2,4-DCP. Table 1 Parameters of the 2,4-DCP decomposition process Type of discharge system Initial concentration, g×m − 3 /cm − 3 Rate constant, s- 1 Decomposition rate at τ R →0, cm − 3 ×s − 1 Energy efficiency φ, molecules per 100 eV DBD 1.0/3.7×10 15 (0.23±0.03) (0.85±0.08) ×10 15 (1.7±0.3) ×10 − 2 DBD 0.46/1.7×10 15 (0.17±0.03) (0.29±0.07)×10 15 (0.58±0.04) ×10 − 2 DBD + catalyst 0.93/3.4×10 15 (0.42±0.04) (1.44±0.1)×10 15 (2.9±0.4) ×10 − 2 The degree of decomposition also weakly depends on the initial concentration. (Fig. 4). For this reason, decomposition rates are also approximately directly proportional to concentration. This situation may occur when the primary reaction of destruction of 2,4-DCP is electron impact. The rate constant of this reaction is determined by the nonequilibrium electron energy distribution function (EEDF). The EEDF, in turn, depends on the magnitude of the reduced electric field strength E/N and the composition of the gas phase. The main influence on the formation of the EEDF is exerted by the transport cross sections for the interaction of electrons with molecules. The characteristic value of the transport cross section for the O 2 molecule is ~ 8×10 − 16 cm 2 [ 30 ], and for the phenol molecule - ~2.5×10 − 15 cm 2 [ 31 ]. In the Boltzmann equation, the solution of which determines the type of EEDF, the cross-sectional values are multiplied by the mole fractions of the corresponding components. Since the mole fraction of 2,4-DCP is ~ 10 − 4 , one can expect a negligible effect of the 2,4-DCP content on the EEDF and rate constants involving electrons. For a specific discharge power of 0.8 W/cm 3 , the average value of E/N over the period is 150 Td, and the current value is 1 mA [ 32 ]. Solving the Boltzmann equation for the indicated parameters as described in [ 33 ], we calculated the electron drift velocity ( V D ). Using the equation j = N e ×e×V D ( e is the electron charge, j is the current density), we estimated the average electron concentration ( N e ), which turned out to be equal to ~ 7 × 10 6 cm − 3 . Using the effective constants ( K eff ) from Table 1 , we can estimate the rate constant for destruction of 2,4-DCP by electron impact ( E D ) from the relation K D =K eff /N e . The calculation gives a value of (2.3–3.3) ×10 − 8 cm − 3 × s − 1 . This value is quite reasonable, since at E/N = 150 Td this constant is obtained with a process cross section of less than 10 − 17 cm 2 . This cross-sectional value is typical for the processes of dissociation and dissociative attachment. The use of a catalyst significantly improves the performance of the decomposition process. Decomposition rates and energy efficiencies are almost doubled. Based on the results obtained, we cannot explain the mechanism of action of the catalyst. This result may be associated not only with the acceleration of the rates of heterogeneous reactions on the surface of the catalyst, but also with the fact that the properties of the discharge in the catalyst zone differ from the properties of the discharge in the discharge zone without it. The discharge in the catalyst zone consists of individual microdischarges burning in the spaces between the catalyst granules. In any case, with or without a catalyst, increasing the power applied to the discharge leads to an increase in the degree of 2,4-DCP decomposition (Fig. 5 ). This result is quite expected, since an increase in power leads to an increase in the rates of formation of almost all active particles, as well as the average energy and concentration of electrons [ 34 ]. As the analysis results showed, the decomposition products of 2,4-DCP are CO 2 molecules and chlorine molecules (atoms). No other products were detected in measurable quantities. The results of calculations of balances for carbon atoms and chlorine molecules are given in Table 2 . Table 2 Destruction products Concentration at the inlet to the reactor, g/m 3 Experimental conditions Maximum concentration СО 2 , mg/m 3 Maximum concentration Сl 2 , mg/m 3 Contribution of CO 2 to the carbon balance,% Contribution of Cl 2 to the chlorine balance, % 1 DBD (0.8 W/сm 3 ) 1460 283 72 52 0.93 DBD + catalyst (0.8 W/сm 3 ) 1490 243 99 60 These data show that during a discharge without a catalyst, some amount of carbon and chlorine remains in the discharge system. The formation of something like a polymer film on the walls of the reactor is observed. In the presence of a catalyst, almost all of the carbon contained in 2,4-DCP is converted to CO 2 . But some of the chlorine produced apparently reacts with the internal metal electrode, forming non-volatile products. An important indicator of the feasibility of using a catalyst is the preservation of its activity during operation. Data characterizing the preservation of the catalyst's performance during operation are presented in Fig. 6 . It can be seen that the activity of the catalyst remains almost unchanged after 7 hours of operation. Conclusions Thus, the atmospheric pressure dielectric barrier discharge in oxygen is an effective tool for cleaning gases from vapors of chlorinated phenols. Under the influence of a discharge, chlorophenol is quickly destroyed with the formation of chlorine and carbon dioxide molecules in the gas phase. The resulting molecules can be easily converted by simple chemical methods into non-toxic carbonate and chloride ions. The use of a catalyst in the discharge zone significantly accelerates destruction, increases the degree of decomposition and the energy indicators of the process. In a discharge with a catalyst, in contrast to a discharge without a catalyst, the formation of any condensed products on the walls of the reactor is not observed. Declarations Acknowledgements The work was supported by the Ministry of Higher Education and Science of the Russian Federation, project no. FZZW-2023-0010 using facilities of the Center for Shared Use of Scientific Equipment at the Ivanovo State University of Chemistry and Technology (with the support of the Ministry of Higher Education and Science of Russia, agreement no. 075-15-2021-671). Authors contributions All authors contributed to the writing of this study. Data collection and analysis were performed by K.A. Lapshova, G.I. Gusev and E.Yu. Kvitkova. A.A. Gushchin, V.V. Rybkin and V.V. Grinevich wrote background and discussion parts, made calculations and drawing figures and tables. T.V. Izvekova and N.E. Gordina were responsible for the designing and literature search. The first draft of the manuscript was written by V.V. Grinevich. A.A. Gushchin along with the other authors reviewed and edited all versions of the manuscript. A.A. Gushchin was also responsible for project administration and supervision. All authors read and approved the final manuscript. Funding The work was supported by the Ministry of Higher Education and Science of the Russian Federation, project no. FZZW-2023-0010. Conflict of interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Ethical approval This article does not contain any studies with human participants or animals performed by any of the authors. Consent of publish We authors accept and confirm responsibility for releasing this material on behalf of any and all co-authors. 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Cite Share Download PDF Status: Published Journal Publication published 17 Mar, 2024 Read the published version in Plasma Chemistry and Plasma Processing → Version 1 posted Editorial decision: Revision requested 25 Jan, 2024 Reviews received at journal 22 Jan, 2024 Reviewers agreed at journal 18 Jan, 2024 Reviewers invited by journal 16 Jan, 2024 Submission checks completed at journal 11 Jan, 2024 Editor assigned by journal 11 Jan, 2024 First submitted to journal 10 Jan, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-3850529","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":266430805,"identity":"79adbc46-d01d-4e92-bb84-b4d70b0a61dc","order_by":0,"name":"K. А. Lapshova","email":"","orcid":"","institution":"Ivanovo State University of Chemistry and Technology","correspondingAuthor":false,"prefix":"","firstName":"K.","middleName":"А.","lastName":"Lapshova","suffix":""},{"id":266430806,"identity":"2f81b913-4cde-48e3-996a-c5dedae318b5","order_by":1,"name":"N. E. Gordina","email":"","orcid":"","institution":"Ivanovo State University of Chemistry and Technology","correspondingAuthor":false,"prefix":"","firstName":"N.","middleName":"E.","lastName":"Gordina","suffix":""},{"id":266430807,"identity":"8128c960-e8a0-4d2a-a009-6955881f598c","order_by":2,"name":"E. Yu. Kvitkova","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAuUlEQVRIiWNgGAWjYBACAxCRUGHDww+kDzwgWsuDM2kykg1ALQnEamF82HbYxuAAyDpitJhL5D5gSGxL4zG+dvgh0JZ7iQ2EtFjOSDdgSDhnw2N2O80AqKWYsBaDG2lA95SlAbUkgLQkEKuF7TCP8ez0D6RoaTvMYyCdQ6Qtlj3PgFrOpPFI3M4pOJBgkGBMUIs5exoD448KG3v+2embP3yoSJAlqAUI2H8guZMI9aNgFIyCUTAKCAMAIIk/FwMaPiQAAAAASUVORK5CYII=","orcid":"","institution":"Ivanovo State University of Chemistry and Technology","correspondingAuthor":true,"prefix":"","firstName":"E.","middleName":"Yu.","lastName":"Kvitkova","suffix":""},{"id":266430808,"identity":"668d9e81-62f4-4fa1-808f-2b815e0b2b86","order_by":3,"name":"T. V. Izvekova","email":"","orcid":"","institution":"Ivanovo State University of Chemistry and Technology","correspondingAuthor":false,"prefix":"","firstName":"T.","middleName":"V.","lastName":"Izvekova","suffix":""},{"id":266430809,"identity":"16c605a8-3bfa-42f3-be4c-ec05331d1155","order_by":4,"name":"V. I. Grinevich","email":"","orcid":"","institution":"Ivanovo State University of Chemistry and Technology","correspondingAuthor":false,"prefix":"","firstName":"V.","middleName":"I.","lastName":"Grinevich","suffix":""},{"id":266430810,"identity":"3abde19b-f3b7-458b-bb69-fd7ff474b754","order_by":5,"name":"G. I. Gusev","email":"","orcid":"","institution":"Ivanovo State University of Chemistry and Technology","correspondingAuthor":false,"prefix":"","firstName":"G.","middleName":"I.","lastName":"Gusev","suffix":""},{"id":266430811,"identity":"e04011de-cb36-4b77-92cd-407ff6c95013","order_by":6,"name":"V. V. Rybkin","email":"","orcid":"","institution":"Ivanovo State University of Chemistry and Technology","correspondingAuthor":false,"prefix":"","firstName":"V.","middleName":"V.","lastName":"Rybkin","suffix":""},{"id":266430812,"identity":"5c24e25b-0647-45cd-b50f-55ff7ae48e16","order_by":7,"name":"A. A. Gushchin","email":"","orcid":"","institution":"Ivanovo State University of Chemistry and Technology","correspondingAuthor":false,"prefix":"","firstName":"A.","middleName":"A.","lastName":"Gushchin","suffix":""}],"badges":[],"createdAt":"2024-01-10 14:16:04","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3850529/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3850529/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s11090-024-10462-y","type":"published","date":"2024-03-17T19:48:47+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":49536435,"identity":"87961b1a-2ac7-4b1b-9482-00776c8b125e","added_by":"auto","created_at":"2024-01-12 16:03:00","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":74957,"visible":true,"origin":"","legend":"\u003cp\u003eThe scheme of the experimental setup\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-3850529/v1/6854360fd1bad2f62e37717f.jpeg"},{"id":49536438,"identity":"428a5292-3fb5-49d6-9de4-0f6683ad7452","added_by":"auto","created_at":"2024-01-12 16:03:00","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":115580,"visible":true,"origin":"","legend":"\u003cp\u003eAdsorption of 2,4-DCP on a catalyst. The dots are an experiment. Line – calculation according to equation (8)\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3850529/v1/2dbe2afbc4c4a539abd65862.jpg"},{"id":49536437,"identity":"6ebe4c58-b908-4ba0-bf16-dc1abe44598e","added_by":"auto","created_at":"2024-01-12 16:03:00","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":153313,"visible":true,"origin":"","legend":"\u003cp\u003eConcentration of 2,4-DCP as a function of residence time. \u003cem\u003e1,3\u003c/em\u003e - DBD. \u003cem\u003e2\u003c/em\u003e - DBD with catalyst. The specific discharge power is 0.8 W/cm\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3850529/v1/22aada90f18060d97344bf22.jpg"},{"id":49536436,"identity":"f2d84473-7666-4923-b0a4-200abe813647","added_by":"auto","created_at":"2024-01-12 16:03:00","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":143322,"visible":true,"origin":"","legend":"\u003cp\u003eDependence of the degree of decomposition on the initial concentration. Specific power is 0.8 W/cm\u003csup\u003e3\u003c/sup\u003e. Gas residence time is 14 s.\u003cem\u003e 1\u003c/em\u003e-discharge with catalyst. \u003cem\u003e2\u003c/em\u003e- discharge without catalyst\u003c/p\u003e","description":"","filename":"4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3850529/v1/d0ed322fff8bb0d91f7a2483.jpg"},{"id":49536440,"identity":"dc3bbac1-7654-407b-9dea-83c8245ef500","added_by":"auto","created_at":"2024-01-12 16:03:00","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":227830,"visible":true,"origin":"","legend":"\u003cp\u003eDependence of the concentration of 2,4-DCP and the degree of decomposition on the inputted power. Residence time is 14 s. \u003cem\u003e1\u003c/em\u003e-discharge with catalyst. \u003cem\u003e2\u003c/em\u003e- discharge without catalyst\u003c/p\u003e","description":"","filename":"5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3850529/v1/4330e720f5cfc0ae9eb3f8e1.jpg"},{"id":49536439,"identity":"2a4b2230-b17d-46c8-845e-d24acdd9921c","added_by":"auto","created_at":"2024-01-12 16:03:00","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":191567,"visible":true,"origin":"","legend":"\u003cp\u003eDependence of the degree of decomposition (\u003cem\u003e1\u003c/em\u003e) and concentration (\u003cem\u003e2\u003c/em\u003e) on the operating time of the reactor. Residence time is 14 s. Power is 0.8 W/cm\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e","description":"","filename":"6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3850529/v1/0bbd947c765fa9ecffb06871.jpg"},{"id":52848110,"identity":"48a1880f-4ddf-4f8c-8233-3ba2eb6501fc","added_by":"auto","created_at":"2024-03-17 19:48:56","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":649496,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3850529/v1/716d7d52-da34-434c-94f8-8bb92b8943fa.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Destruction of 2,4-dichlorophenol vapor in a process involving the combined action of DBD in oxygen and a catalyst","fulltext":[{"header":"Introduction","content":"\u003cp\u003e2,4 dichlorophenol (2,4-DCP) belongs to a group of VOCs (volatile organic compounds) that are ubiquitous [\u003cspan additionalcitationids=\"CR2 CR3 CR4 CR5\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. A peculiarity of 2,4-DCP (as well as other organochlorine compounds) is that it concentrates when moving along trophic chains [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. The main methods for suppressing emissions and discharges of such compounds into the environment involve the use of thermal methods [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. However, in this case, complete neutralization requires the use of high temperatures (more than 1200 degrees C) and long combustion times to prevent the formation of more dangerous compounds such as dioxins [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. For this reason, methods based on the use of plasma of various types of gas discharges for VOC removal are attracting increased interest from researchers [\u003cspan additionalcitationids=\"CR13 CR14 CR15 CR16 CR17\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Previously [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] it was studied the decomposition of 2,4-DCP vapor in an atmospheric pressure barrier discharge in oxygen. The process showed quite high efficiency (the degree of decomposition of 2,4-DCP reached 90%). But a drawback was also identified. During operation, a polymer film formed on the inner surface of the reactor and the process performance deteriorated. To eliminate this phenomenon and improve efficiency, in this study we tried a process in which a catalyst was introduced into the plasma zone, because among various VOC elimination strategies, catalytic oxidation is considered one of the most promising technologies for the complete oxidation of VOCs from municipal and industrial waste streams [\u003cspan additionalcitationids=\"CR20 CR21 CR22 CR23 CR24 CR25\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e].\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n\u003ch2\u003eDescription of the Experimental Setup\u003c/h2\u003e\n\u003cp\u003eThe experimental setup is shown in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. This is a cylindrical reactor with an internal diameter of 22 mm made of Pyrex glass, which is a dielectric barrier. An external electrode made of aluminum foil was located outside the glass tube. The internal electrode was an aluminum rod with a diameter of 16 mm. The length of the discharge zone was 8 cm. A catalyst weighing 1 g was located in the gap between the inner electrode and the inner wall of the Pyrex tube. The catalyst was fixed with Teflon perforated washers placed on the internal electrode.\u003c/p\u003e\n\u003cp\u003eTo excite the discharge, an alternating voltage source (1000 Hz) was used, which provided an amplitude voltage of up to 60 kV. The voltage drop across the discharge was measured using a high-voltage probe (2000:1). To determine the discharge current, the voltage drop across a 100 Ohm resistance connected in series with the reactor power circuit was measured. A two-channel digital oscilloscope GW Instek GDS-2072 (Instek, Taiwan) was used for measurements. The rms voltage varied in the range of (8\u0026ndash;10) kV. In this case, the root mean square value of the current varied from 0.2 to 1.0 mA. The power introduced into the discharge was calculated by numerical integration over the period of the product of current and voltage.\u003c/p\u003e\n\u003cp\u003eThe plasma-forming gas was technical oxygen (99.8%), which was supplied to the discharge device using a gas flow former Khromatek-Kristall FGP (Russia) with a volumetric flow rate of 1\u0026ndash;3 cm\u003csup\u003e3\u003c/sup\u003e/s.\u003c/p\u003e\n\u003cp\u003eThe concentration of 2,4 DCP was set by the temperature of the cell through which the oxygen flow passed. The range of concentration changes was 0.01-1 g/m\u003csup\u003e3\u003c/sup\u003e. To analyze the products, the gas leaving the reactor was passed through an absorption vessel containing ethanol.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n\u003ch2\u003eAnalysis methods\u003c/h2\u003e\n\u003cp\u003eTo quantitatively determine the content of 2,4-DCP at the inlet and outlet of the discharge device, the gas chromatography method (chromatograph Khromatek Kristall-5000, Russia) with an electron capture detector (carrier gas - nitrogen) was used. The chromatograph was preliminarily calibrated using a series of standard solutions of 2,4-DCP in ethanol.\u003c/p\u003e\n\u003cp\u003eThe concentration of carbon dioxide was also determined chromatographically using a methanator and a flame ionization detector.\u003c/p\u003e\n\u003cp\u003eThe gaseous chlorine formed during the decomposition of 2,4-DCP was absorbed by water, and then active chlorine was determined by the titrimetric method, based on the fact that free chlorine, hypochlorous acid, hypochlorite ion, mono- and dichloramines in an acidic environment react with potassium iodide to release iodine, which was titrated with sodium thiosulfate in the presence of starch [\u003cspan class=\"CitationRef\"\u003e27\u003c/span\u003e].\u003c/p\u003e\n\u003cp\u003eThe probable degradation products of 2,4-DCP were determined by gas chromatography-mass spectral method (GCMS-QP2010Ultra, Shimadzu Europa GMBH). Toluene and n-hexane were used as extractants in sample preparation.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\n\u003ch2\u003eCalculated parameters\u003c/h2\u003e\n\u003cp\u003eResidence time of the gas in the reactor, calculated as\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u0026tau;\u003c/em\u003e \u003csub\u003e \u003cem\u003eR\u003c/em\u003e \u003c/sub\u003e\u0026thinsp;\u003cem\u003e=\u0026thinsp;L\u0026sdot;S/Q, s\u003c/em\u003e\u003csup\u003e\u003cem\u003e\u0026minus;\u0026thinsp;1\u003c/em\u003e\u003c/sup\u003e (1)\u003c/p\u003e\n\u003cp\u003ewhere \u003cem\u003eL\u003c/em\u003e is the length of the discharge zone (\u003cem\u003eL\u003c/em\u003e\u0026thinsp;=\u0026thinsp;8 cm), \u003cem\u003eS\u003c/em\u003e is the area of the annular gap of the reactor (S\u0026thinsp;=\u0026thinsp;1.79 cm\u003csup\u003e2\u003c/sup\u003e) was 4\u0026ndash;14 s, \u003cem\u003eQ\u003c/em\u003e is volumetric gas flow (l/s).\u003c/p\u003e\n\u003cp\u003eThe degree of decomposition (\u0026alpha;) of 2,4-DCP was calculated from the relationship:\u003c/p\u003e\n\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e \u003cspan class=\"mathinline\"\u003e\\(\\alpha =\\frac{{C}_{in}-{C}_{out}}{{C}_{in}}\\times 100\\)\u003c/span\u003e \u003c/span\u003e, % (2)\u003c/p\u003e\n\u003cp\u003ewhere \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003ein\u003c/em\u003e\u003c/sub\u003e is the concentration of 2,4-DCP at the inlet to the reactor, \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003eout\u003c/em\u003e\u003c/sub\u003e is the concentration of 2,4-DCP at the outlet of the reactor.\u003c/p\u003e\n\u003cp\u003eKinetic dependences (dependence of concentration on gas residence time) were processed under the assumption that decomposition occurs irreversibly in a reaction of the first kinetic order in the concentration of 2,4-DCP. For this case, the kinetic equation has the form [\u003cspan class=\"CitationRef\"\u003e28\u003c/span\u003e]:\u003c/p\u003e\n\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e \u003cspan class=\"mathinline\"\u003e\\({C}_{out}={C}_{in}\\times \\text{e}\\text{x}\\text{p}(-{K}_{D}\\times {\\tau }_{R})\\)\u003c/span\u003e \u003c/span\u003e, mg m\u003csup\u003e\u0026minus;3\u003c/sup\u003e (3)\u003c/p\u003e\n\u003cp\u003ewhere \u003cem\u003eK\u003c/em\u003e\u003csub\u003e\u003cem\u003eD\u003c/em\u003e\u003c/sub\u003e is the effective decomposition rate constant, \u003cem\u003e\u0026tau;\u003c/em\u003e\u003csub\u003e\u003cem\u003eR\u003c/em\u003e\u003c/sub\u003e is the residence time.\u003c/p\u003e\n\u003cp\u003eEq.\u0026nbsp;(3) describes the experimental data quite well (coefficient of determination R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.97).\u003c/p\u003e\n\u003cp\u003eBased on the kinetic data, we also calculated energy efficiency of decomposition \u0026phi; (the number of decayed molecules per 100 eV of energy input) and the rate of decomposition process W. Since the values of \u003cem\u003e\u0026phi;\u003c/em\u003e and \u003cem\u003eW\u003c/em\u003e depend on the contact time, \u003cem\u003e\u0026phi;\u003c/em\u003e and \u003cem\u003eW\u003c/em\u003e were determined for the time \u003cem\u003e\u0026tau;\u003c/em\u003e\u003csub\u003e\u003cem\u003eR\u003c/em\u003e\u003c/sub\u003e \u0026rarr; 0. The ratios used for the calculation were as follows:\u003c/p\u003e\n\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e \u003cspan class=\"mathinline\"\u003e\\(\\phi =\\frac{W({\\tau }_{R}=0)\\times {V}_{R}\\times 1.6\\times {10}^{-19}\\times 100}{P}\\)\u003c/span\u003e \u003c/span\u003e, molecules per 100 eV (4)\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eW(\u0026tau;\u003c/em\u003e \u003csub\u003e \u003cem\u003eR\u003c/em\u003e \u003c/sub\u003e\u0026thinsp;\u003cem\u003e=\u0026thinsp;0)\u0026thinsp;=\u0026thinsp;K\u003c/em\u003e\u003csub\u003e\u003cem\u003eD\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e\u0026times;C\u003c/em\u003e\u003csub\u003e\u003cem\u003ein\u003c/em\u003e\u003c/sub\u003e (5)\u003c/p\u003e\n\u003cp\u003ewhere \u003cem\u003eV\u003c/em\u003e\u003csub\u003e\u003cem\u003eR\u003c/em\u003e\u003c/sub\u003e \u0026ndash; volume of plasma zone (mL\u003csup\u003e3\u003c/sup\u003e), \u003cem\u003eW\u003c/em\u003e \u0026ndash; decomposition rate (mL\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), 1.6 \u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;19\u003c/sup\u003e charge of an electron (C), \u003cem\u003eP\u003c/em\u003e \u0026ndash; the inputted power (W).\u003c/p\u003e\n\u003cp\u003eBased on the measured concentrations of destruction products, the balance of carbon and chlorine was also assessed. For this we used the ratio:\u003c/p\u003e\n\u003cdiv id=\"Equ1\" class=\"Equation\"\u003e\n\u003cdiv id=\"FileID_Equ1\" class=\"mathdisplay\"\u003e$$\\delta =\\frac{{Y}_{P}}{Y}$$\u003c/div\u003e\n\u003cdiv class=\"EquationNumber\"\u003e6\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003ewhere \u003cem\u003eY\u003c/em\u003e\u003csub\u003e\u003cem\u003eP\u003c/em\u003e\u003c/sub\u003e is the content of the corresponding element in the product, and \u003cem\u003eY\u003c/em\u003e is the content of the same element in decomposed 2,4-DCP.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\n\u003ch2\u003eCharacterization of the Catalyst\u003c/h2\u003e\n\u003cp\u003eThe starting material for preparing the catalyst was natural vermiculite from the Kovdor (Russia) deposit. The size of vermiculite grains was up to 0.6 mm. The chemical composition corresponded to: SiO\u003csub\u003e2\u003c/sub\u003e (37.2%), Al\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e (6.2%), CaO (15.3%), Fe\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e (19%), MgO (13.1%). To improve the catalytic properties, the catalyst contained zirconium oxide. To obtain it, zirconium oxychloride octahydrate ZrOCl\u003csub\u003e2\u003c/sub\u003e∙8H\u003csub\u003e2\u003c/sub\u003eO (CAS No. 13520\u0026ndash;92\u0026ndash;8) was added to the original vermiculite. The amount of salt was such that the zirconium content was 5 weights percent. The resulting mixture was activated mechanochemically. After this, granules with a diameter of 3 mm were molded from the activated mass and subjected to thermal firing. The catalyst preparation procedure is described in more detail in [\u003cspan class=\"CitationRef\"\u003e29\u003c/span\u003e]. The resulting catalyst had a specific surface area of 15.1\u0026plusmn;0.8 m\u003csup\u003e2\u003c/sup\u003e/g and a pore volume of 0.023\u0026plusmn;0.001 cm\u003csup\u003e3\u003c/sup\u003e/g. These values were calculated based on measurements of nitrogen adsorption-desorption isotherms at 77 K using the BET theory. Also, the resulting catalyst turned out to be a good sorbent for 2,4-DCP (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eFrom the obtained dependence one can obtain some formal characteristics of adsorption. Let us assume that adsorption occurs on active surface centers of the same type. Then, approximately, we can write the following kinetic equations\u003c/p\u003e\n\u003cdiv id=\"Equ2\" class=\"Equation\"\u003e\n\u003cdiv id=\"FileID_Equ2\" class=\"mathdisplay\"\u003e$$\\frac{d{C}_{g}}{dt}=-{K}_{A}\\times {C}_{g}\\times {C}_{S}$$\u003c/div\u003e\n\u003cdiv class=\"EquationNumber\"\u003e6\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Equ3\" class=\"Equation\"\u003e\n\u003cdiv id=\"FileID_Equ3\" class=\"mathdisplay\"\u003e$$\\frac{d{C}_{s}}{dt}=-{K}_{A}\\times {C}_{g}\\times {C}_{g}$$\u003c/div\u003e\n\u003cdiv class=\"EquationNumber\"\u003e7\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003ewhere \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003eg\u003c/em\u003e\u003c/sub\u003e is the concentration in the gas phase, \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e is the concentration of active centers on the surface, \u003cem\u003eK\u003c/em\u003e\u003csub\u003e\u003cem\u003eA\u003c/em\u003e\u003c/sub\u003e is the effective adsorption rate constant.\u003c/p\u003e\n\u003cp\u003eThe solution to the system of Eq.\u0026nbsp;(\u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e) and Eq.\u0026nbsp;(\u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e) with the initial conditions \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003eg\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e=C\u003c/em\u003e\u003csub\u003e\u003cem\u003eg\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u003cem\u003e0\u003c/em\u003e\u003c/sup\u003e and \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e=C\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u003cem\u003e0\u003c/em\u003e\u003c/sup\u003e at t\u0026thinsp;=\u0026thinsp;0 has the form:\u003c/p\u003e\n\u003cdiv id=\"Equ4\" class=\"Equation\"\u003e\n\u003cdiv id=\"FileID_Equ4\" class=\"mathdisplay\"\u003e$${C}_{g}\\left(t\\right)=\\frac{{C}_{g}^{0}-{C}_{s}^{0}}{1-\\frac{{C}_{s}^{0}}{{C}_{g}^{0}}\\times \\text{e}\\text{x}\\text{p}[-{K}_{A}\\times ({C}_{g}^{0}-{C}_{s}^{0})\\times t]}$$\u003c/div\u003e\n\u003cdiv class=\"EquationNumber\"\u003e8\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003eEq.\u0026nbsp;(\u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e) describes the experimental dependence very well (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). The coefficient of determination is R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.999. Processing the adsorption curve gives the following parameter values: \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003eg\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u003cem\u003e0\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e-C\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u003cem\u003e0\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e=\u003c/em\u003e(14.7\u0026plusmn;1.7) mg/m\u003csup\u003e3\u003c/sup\u003e, \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u003cem\u003e0\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e/ C\u003c/em\u003e\u003csub\u003e\u003cem\u003eg\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u003cem\u003e0\u003c/em\u003e\u003c/sup\u003e=0.88\u0026plusmn;0.01, \u003cem\u003eK\u003c/em\u003e\u003csub\u003e\u003cem\u003eA\u003c/em\u003e\u003c/sub\u003e\u0026times;( \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003eg\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u003cem\u003e0\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e-C\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u003cem\u003e0\u003c/em\u003e\u003c/sup\u003e)\u0026thinsp;=\u0026thinsp;0.06\u0026plusmn;0.02 min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e or (1\u0026plusmn;0.3) \u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. These quantities give the following values: C\u003csub\u003eg\u003c/sub\u003e=123\u0026plusmn;15 mg/m\u003csup\u003e3\u003c/sup\u003e (experiment \u0026minus;\u0026thinsp;125 mg/m\u003csup\u003e3\u003c/sup\u003e), \u003cem\u003eC\u003c/em\u003e\u003csub\u003e\u003cem\u003es\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u003cem\u003e0\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e=\u003c/em\u003e108 mg/m\u003csup\u003e3\u003c/sup\u003e, \u003cem\u003eK\u003c/em\u003e\u003csub\u003e\u003cem\u003eA\u003c/em\u003e\u003c/sub\u003e=0.0041 m\u003csup\u003e3\u003c/sup\u003e/(mg\u0026times;min) or 1.1\u0026times;10\u003csup\u003e4\u003c/sup\u003e l/(mol\u0026times;s).\u003c/p\u003e\n\u003cp\u003eIn order to avoid the influence of absorption on the kinetics of plasma destruction, in all experiments the catalyst was saturated with 2,4-DCP before ignition of the discharge.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Results and Discussion","content":"\u003cp\u003eFigure\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e shows the kinetics of the decomposition of 2,4-DCP at various initial concentrations in the presence of a catalyst and without it. As already noted, the kinetics of decomposition is well described by a formal first-order law for the concentration of 2,4-DCP (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.97).\u003c/p\u003e\n\u003cp\u003eThe effective rate constants (\u003cem\u003eK\u003c/em\u003e\u003csub\u003e\u003cem\u003eeff\u003c/em\u003e\u003c/sub\u003e), degradation rates, and energy yields of decomposition found from these data are presented in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. It can be seen that at a constant discharge power, the effective rate constants, within the measurement error, do not depend on the initial concentration of 2,4-DCP.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eParameters of the 2,4-DCP decomposition process\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eType of discharge system\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eInitial concentration, g\u0026times;m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e/cm\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRate constant, s-\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDecomposition rate at \u003cem\u003e\u0026tau;\u003c/em\u003e\u003csub\u003e\u003cem\u003eR\u003c/em\u003e\u003c/sub\u003e\u0026rarr;0, cm\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e \u0026times;s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eEnergy efficiency \u0026phi;, molecules per 100 eV\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\"\u003e\n \u003cp\u003eDBD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.0/3.7\u0026times;10\u003csup\u003e15\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e(0.23\u0026plusmn;0.03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e(0.85\u0026plusmn;0.08) \u0026times;10\u003csup\u003e15\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e(1.7\u0026plusmn;0.3) \u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDBD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.46/1.7\u0026times;10\u003csup\u003e15\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e(0.17\u0026plusmn;0.03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e(0.29\u0026plusmn;0.07)\u0026times;10\u003csup\u003e15\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e(0.58\u0026plusmn;0.04) \u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDBD\u0026thinsp;+\u0026thinsp;catalyst\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.93/3.4\u0026times;10\u003csup\u003e15\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e(0.42\u0026plusmn;0.04)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e(1.44\u0026plusmn;0.1)\u0026times;10\u003csup\u003e15\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e(2.9\u0026plusmn;0.4) \u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003eThe degree of decomposition also weakly depends on the initial concentration. (Fig. 4).\u003c/p\u003e\n\u003c/div\u003e\n\u003cp\u003eFor this reason, decomposition rates are also approximately directly proportional to concentration. This situation may occur when the primary reaction of destruction of 2,4-DCP is electron impact. The rate constant of this reaction is determined by the nonequilibrium electron energy distribution function (EEDF). The EEDF, in turn, depends on the magnitude of the reduced electric field strength E/N and the composition of the gas phase. The main influence on the formation of the EEDF is exerted by the transport cross sections for the interaction of electrons with molecules. The characteristic value of the transport cross section for the O\u003csub\u003e2\u003c/sub\u003e molecule is ~\u0026thinsp;8\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;16\u003c/sup\u003e cm\u003csup\u003e2\u003c/sup\u003e [\u003cspan class=\"CitationRef\"\u003e30\u003c/span\u003e], and for the phenol molecule - ~2.5\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;15\u003c/sup\u003e cm\u003csup\u003e2\u003c/sup\u003e [\u003cspan class=\"CitationRef\"\u003e31\u003c/span\u003e]. In the Boltzmann equation, the solution of which determines the type of EEDF, the cross-sectional values are multiplied by the mole fractions of the corresponding components. Since the mole fraction of 2,4-DCP is ~\u0026thinsp;10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e, one can expect a negligible effect of the 2,4-DCP content on the EEDF and rate constants involving electrons. For a specific discharge power of 0.8 W/cm\u003csup\u003e3\u003c/sup\u003e, the average value of E/N over the period is 150 Td, and the current value is 1 mA [\u003cspan class=\"CitationRef\"\u003e32\u003c/span\u003e]. Solving the Boltzmann equation for the indicated parameters as described in [\u003cspan class=\"CitationRef\"\u003e33\u003c/span\u003e], we calculated the electron drift velocity (\u003cem\u003eV\u003c/em\u003e\u003csub\u003e\u003cem\u003eD\u003c/em\u003e\u003c/sub\u003e). Using the equation \u003cem\u003ej\u0026thinsp;=\u0026thinsp;N\u003c/em\u003e\u003csub\u003e\u003cem\u003ee\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e\u0026times;e\u0026times;V\u003c/em\u003e\u003csub\u003e\u003cem\u003eD\u003c/em\u003e\u003c/sub\u003e (\u003cem\u003ee\u003c/em\u003e is the electron charge, \u003cem\u003ej\u003c/em\u003e is the current density), we estimated the average electron concentration (\u003cem\u003eN\u003c/em\u003e\u003csub\u003e\u003cem\u003ee\u003c/em\u003e\u003c/sub\u003e), which turned out to be equal to ~\u0026thinsp;7\u003cem\u003e\u0026times;\u003c/em\u003e10\u003csup\u003e6\u003c/sup\u003e cm\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e. Using the effective constants (\u003cem\u003eK\u003c/em\u003e\u003csub\u003e\u003cem\u003eeff\u003c/em\u003e\u003c/sub\u003e) from Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e, we can estimate the rate constant for destruction of 2,4-DCP by electron impact (\u003cem\u003eE\u003c/em\u003e\u003csub\u003e\u003cem\u003eD\u003c/em\u003e\u003c/sub\u003e) from the relation \u003cem\u003eK\u003c/em\u003e\u003csub\u003e\u003cem\u003eD\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e=K\u003c/em\u003e\u003csub\u003e\u003cem\u003eeff\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e/N\u003c/em\u003e\u003csub\u003e\u003cem\u003ee\u003c/em\u003e\u003c/sub\u003e. The calculation gives a value of (2.3\u0026ndash;3.3) \u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;8\u003c/sup\u003e cm\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e\u003cem\u003e\u0026times;\u003c/em\u003es\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. This value is quite reasonable, since at \u003cem\u003eE/N\u003c/em\u003e\u0026thinsp;=\u0026thinsp;150 Td this constant is obtained with a process cross section of less than 10\u003csup\u003e\u0026minus;\u0026thinsp;17\u003c/sup\u003e cm\u003csup\u003e2\u003c/sup\u003e. This cross-sectional value is typical for the processes of dissociation and dissociative attachment. The use of a catalyst significantly improves the performance of the decomposition process. Decomposition rates and energy efficiencies are almost doubled. Based on the results obtained, we cannot explain the mechanism of action of the catalyst. This result may be associated not only with the acceleration of the rates of heterogeneous reactions on the surface of the catalyst, but also with the fact that the properties of the discharge in the catalyst zone differ from the properties of the discharge in the discharge zone without it. The discharge in the catalyst zone consists of individual microdischarges burning in the spaces between the catalyst granules.\u003c/p\u003e\n\u003cp\u003eIn any case, with or without a catalyst, increasing the power applied to the discharge leads to an increase in the degree of 2,4-DCP decomposition (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e). This result is quite expected, since an increase in power leads to an increase in the rates of formation of almost all active particles, as well as the average energy and concentration of electrons [\u003cspan class=\"CitationRef\"\u003e34\u003c/span\u003e].\u003c/p\u003e\n\u003cp\u003eAs the analysis results showed, the decomposition products of 2,4-DCP are CO\u003csub\u003e2\u003c/sub\u003e molecules and chlorine molecules (atoms). No other products were detected in measurable quantities. The results of calculations of balances for carbon atoms and chlorine molecules are given in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eDestruction products\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eConcentration at the inlet to the reactor, g/m\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eExperimental conditions\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMaximum concentration СО\u003csub\u003e2\u003c/sub\u003e, mg/m\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMaximum concentration\u003c/p\u003e\n \u003cp\u003eСl\u003csub\u003e2\u003c/sub\u003e, mg/m\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eContribution of CO\u003csub\u003e2\u003c/sub\u003e to the carbon balance,%\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eContribution of Cl\u003csub\u003e2\u003c/sub\u003e to the chlorine balance, %\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\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDBD (0.8 W/сm\u003csup\u003e3\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1460\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e283\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDBD\u0026thinsp;+\u0026thinsp;catalyst (0.8 W/сm\u003csup\u003e3\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1490\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e243\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e60\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\u003eThese data show that during a discharge without a catalyst, some amount of carbon and chlorine remains in the discharge system. The formation of something like a polymer film on the walls of the reactor is observed. In the presence of a catalyst, almost all of the carbon contained in 2,4-DCP is converted to CO\u003csub\u003e2\u003c/sub\u003e. But some of the chlorine produced apparently reacts with the internal metal electrode, forming non-volatile products.\u003c/p\u003e\n\u003cp\u003eAn important indicator of the feasibility of using a catalyst is the preservation of its activity during operation. Data characterizing the preservation of the catalyst\u0026apos;s performance during operation are presented in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e.\u003c/p\u003e\n\u003cp\u003eIt can be seen that the activity of the catalyst remains almost unchanged after 7 hours of operation.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThus, the atmospheric pressure dielectric barrier discharge in oxygen is an effective tool for cleaning gases from vapors of chlorinated phenols. Under the influence of a discharge, chlorophenol is quickly destroyed with the formation of chlorine and carbon dioxide molecules in the gas phase. The resulting molecules can be easily converted by simple chemical methods into non-toxic carbonate and chloride ions. The use of a catalyst in the discharge zone significantly accelerates destruction, increases the degree of decomposition and the energy indicators of the process. In a discharge with a catalyst, in contrast to a discharge without a catalyst, the formation of any condensed products on the walls of the reactor is not observed.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u0026nbsp;\u003c/strong\u003eThe work was supported by the Ministry of Higher Education and Science of the Russian Federation, project no. FZZW-2023-0010 using facilities of the Center for Shared Use of Scientific Equipment at the Ivanovo State University of Chemistry and Technology (with the support of the Ministry of Higher Education and Science of Russia, agreement no. 075-15-2021-671).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors contributions\u0026nbsp;\u003c/strong\u003eAll authors contributed to the writing of this study. Data collection and analysis were performed by K.A. Lapshova, G.I. Gusev and E.Yu. Kvitkova. A.A. Gushchin, V.V. Rybkin and V.V. Grinevich wrote background and discussion parts, made calculations and drawing figures and tables. T.V. Izvekova and N.E. Gordina were responsible for the designing and literature search. The first draft of the manuscript was written by V.V. Grinevich. A.A. Gushchin along with the other authors reviewed and edited all versions of the manuscript. A.A. Gushchin was also responsible for project administration and supervision. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003eThe work was supported by the Ministry of Higher Education and Science of the Russian Federation, project no. FZZW-2023-0010.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest\u0026nbsp;\u003c/strong\u003eThe authors 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\u003cp\u003e\u003cstrong\u003eEthical approval\u0026nbsp;\u003c/strong\u003eThis article does not contain any studies with human participants or animals performed by any of the authors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent of publish\u003c/strong\u003e We authors accept and confirm responsibility for releasing this material on behalf of any and all co-authors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and material\u003c/strong\u003e All data generated or analyzed during this study are included in this published article in results section.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eHuang B, Lei C, Wei C, Zeng G (2014) Chlorinated volatile organic compounds (Cl-VOCs) in environment-sources, potential human health impacts, and current remediation technologies. 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Chemosphere 270:129392. https://doi.org/10.1016/j.chemosphere.2020.129392\u003c/li\u003e\n \u003cli\u003eSmirnov SA, Shutov DA, Bobkova ES, Rybkin VV (2015) Physical Parameters and Chemical Composition of a Nitrogen DC Discharge with Water Cathode. Plasma Chem Plasma Process. 35:639-657. doi: 10.1007/s11090-015-9626-9\u003c/li\u003e\n \u003cli\u003eBobkova E, Khodor Y, Kornilova O, Rybkin V (2014) Chemical Composition of Plasma of Dielectric Barrier Dischargeat Atmospheric Pressure with a Liquid Electrode. High Temp 52:511-517. doi: 10.1134/S0018151X14030055\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"plasma-chemistry-and-plasma-processing","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":" Learn more about [Plasma Chemistry and Plasma Processing](https://www.springer.com/journal/11090 ","snPcode":"11090","submissionUrl":"https://mc.manuscriptcentral.com/pcpp","title":"Plasma Chemistry and Plasma Processing","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"2,4-dichlorophenol, destruction, dielectric barrier discharge, catalyst","lastPublishedDoi":"10.21203/rs.3.rs-3850529/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3850529/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIn this work, the process of decomposition of 2,4-dichlorophenol (2,4-DCP) vapor under the influence of atmospheric pressure DBD in oxygen was studied. The studies were carried out in two modes: with a catalyst (natural vermiculite doped with zirconium) and without it. A number of basic characteristics of the catalyst were assessed. The rates and effective rate constants of sorption processes, as well as decomposition processes in plasma and plasma-catalytic systems, were determined. Based on these data, the energy efficiency of the decomposition process was calculated. The data obtained suggested that the initial stage of decomposition is the reaction of interaction of electrons with pollutant molecules. The catalyst has been shown to speed up the decomposition process, increase energy efficiency and the conversion of 2,4-DCP to CO\u003csub\u003e2\u003c/sub\u003e molecules, and prevent the formation of condensed products on the reactor walls. The work estimates the carbon and chlorine balances before and after treatment, which reach a maximum of 99 and 60%, respectively. It was also shown that the catalyst retains its activity for at least 7 hours of continuous operation.\u003c/p\u003e","manuscriptTitle":"Destruction of 2,4-dichlorophenol vapor in a process involving the combined action of DBD in oxygen and a catalyst","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-01-12 16:02:54","doi":"10.21203/rs.3.rs-3850529/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-01-25T18:52:02+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-01-22T11:27:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"48a0f45b-a299-4b64-8817-802c94005adc","date":"2024-01-18T14:10:00+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-01-16T13:43:29+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-01-11T07:30:09+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-01-11T07:30:09+00:00","index":"","fulltext":""},{"type":"submitted","content":"Plasma Chemistry and Plasma Processing","date":"2024-01-10T14:00:47+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"plasma-chemistry-and-plasma-processing","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":" Learn more about [Plasma Chemistry and Plasma Processing](https://www.springer.com/journal/11090 ","snPcode":"11090","submissionUrl":"https://mc.manuscriptcentral.com/pcpp","title":"Plasma Chemistry and Plasma Processing","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"defff952-92f5-4ebe-9b1f-c6dfd1f38746","owner":[],"postedDate":"January 12th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-03-17T19:48:47+00:00","versionOfRecord":{"articleIdentity":"rs-3850529","link":"https://doi.org/10.1007/s11090-024-10462-y","journal":{"identity":"plasma-chemistry-and-plasma-processing","isVorOnly":false,"title":"Plasma Chemistry and Plasma Processing"},"publishedOn":"2024-03-17 19:48:47","publishedOnDateReadable":"March 17th, 2024"},"versionCreatedAt":"2024-01-12 16:02:54","video":"","vorDoi":"10.1007/s11090-024-10462-y","vorDoiUrl":"https://doi.org/10.1007/s11090-024-10462-y","workflowStages":[]},"version":"v1","identity":"rs-3850529","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3850529","identity":"rs-3850529","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}