Animal bones-based chars and activated carbons for xylene adsorption

Animal bones-based chars and activated carbons for xylene adsorption | 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 Animal bones-based chars and activated carbons for xylene adsorption Zuzana Jankovská, Pavlína Peikertová, Jonáš Tokarský, Lenka Matějová This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7931927/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 Beef and pork waste bones, both original and activated, were microwave pyrolyzed to obtain chars usable as adsorbents of xylene from air. Bone activation with potassium carbonate or potassium hydroxide has been tested to increase adsorption efficiency by inducing micropore formation and increasing surface area. Composition and structure of the resulting chars were analyzed by a wide range of methods: proximate and elemental analyses, thermogravimetry, nitrogen physisorption, X-ray fluorescence spectroscopy, Raman spectroscopy, and Fourier-transform infrared spectroscopy. The results demonstrate that the well-developed porous structure including micropores positively affects the adsorption of xylene. Beef and pork waste bones activated with potassium carbonate were proved to be a useful input material for the preparation of cheap and sustainable adsorbents of xylene from air. Environmental Engineering animal bones char xylene microwave activation adsorption Figures Figure 1 1. Introduction Xylene is a typical representative of a group of aromatic compounds known as volatile organic compounds (VOCs). These toxic and carcinogenic substances pose a significant environmental and health risks [ 1 ]. Sources of volatile organic compounds (VOCs) are diverse, from cleaning products and cosmetics to building materials, industrial production, and forest fires, to name a few [ 2 , 3 ]. Both the risks and the variety of sources are the reason for serious societal interest in controlling VOC emissions and reducing the amount of VOCs in the atmosphere [ 3 ]. Adsorption is a highly efficient and easy-to-use method for the treatment of VOCs. Molecular sieves or aerogels are suitable for this purpose, however, chars are the most interesting in terms of low cost and the possibility of using various solid wastes (e.g. biomass[ 4 – 6 ], scrap tyres[ 1 , 4 , 7 ], polymers [ 8 , 9 ], animal bones[ 10 – 20 ]) as input material for production[ 1 , 10 ]. Chars from animal bones were studied as adsorbents of various pollutants such as heavy metals [ 12 , 14 – 16 ], or dyes [ 20 , 21 ], but studies focusing on VOCs removal are almost lacking. This study is one of the few that focuses on the use of microwave pyrolysis of animal bones to obtain bone chars and activated bone chars as adsorbents. In the case of activation, we follow up on our earlier studies, which have already indicated that properly chosen activators contribute to better pore formation and thus improve adsorption efficiency [ 1 , 4 , 22 ]. A novelty of this study is the first-ever demonstration of these chars as adsorbents of xylene from air. 2. Materials and methods 2.1. Raw bones and microwave pyrolysis Xylene p.a. was obtained from VWR International, Inc. (Czech Republic). Beef and pork bones were obtained from Těšínské jatky, s.r.o. (Czech Republic). A microwave power of 200 W was used in this study. Microwave pyrolyzed samples of resulting chars were washed with weak acid, then with distilled water, and finally dried overnight. To enhance formation of pores, the beef and pork bones were also activated with potassium carbonate or potassium hydroxide, immersed in strong acid, then washed with distilled water and dried overnight. Activated bones were then pyrolyzed under the same conditions as the original bones. 2.2. Xylene adsorption Adsorption experiments in this study were performed under the same conditions as the xylene adsorption described in our previous papers [ 1 , 23 , 24 ]. Xylene was adsorbed on both original (not activated) and activated chars. 2.3. Characterisation methods Proximate analysis was performed using LECO TGA 701 analyser. Elemental analysis was performed using LECO CHNS 628 analyser. Thermogravimetric curves were determined using SDT 600 thermogravimeter in a dynamic inert atmosphere. Nitrogen physisorption was performed on Micromeritics 3Flex instrument at 77K X-ray fluorescence spectroscopy was used to semi-quantitatively determine the chemical composition. Spectro XEPOS energy dispersion spectrometer was used. Raman spectra were detected using an XploRA™ Raman spectrometer equipped with 532 nm laser. Fourier-transform infrared (FTIR) spectra were recorded using Nicolet 6700 FT-IR spectrometer. 3. Results and discussion 3.1. Characterization of chars According to the proximate analysis, nearly two times higher amount of fixed carbon was found in char from beef bones compared to char from pork bones. Char from beef bones also contained higher amount of P and Ca compared to char from pork bones. Chemical composition of activated chars allows them to be called Ca-rich chars. The Ca, C, and P content shows that the dominant phase is hydroxyapatite. According to nitrogen physisorption, original chars are mesoporous and macroporous, while activated chars also contain micropores. The specific surface area of chars from activated beef and pork bones increased ~ 2× and ~ 8×, respectively, compared to chars from original bones. Raman spectroscopy of chars revealed the presence of carbon, hydroxyapatite, and calcium carbonate. The ratio of disorder band to graphitic band intensities (I D /I G ) was found to be very similar for all chars. Despite this, spectra of chars from original bones show slightly lower I D /I G ratios compared to chars from activated bones, which indicates a slightly higher amount of graphitic carbon. FTIR spectra confirmed the presence of carbon, hydroxyapatite, and carbonates in the chars. 3.2. Adsorption of xylene onto chars The highest adsorption capacity was shown by char prepared from pork bones activated with potassium carbonate (Fig. 1 ). Using the same activator in the case of beef bones resulted in approximately one-third the adsorption capacity compared to the previous sample. Potassium hydroxide did not prove to be a suitable activator compared to carbonate. In the case of char prepared from original beef bones, about six times the adsorption capacity was achieved compared to char prepared from original pork bones, which was the least effective adsorbent of all the samples studied (Fig. 1 ). Literature search shows that chars prepared from activated bones exhibits higher adsorption capacity compared to chars obtained from waste tires [ 1 ]. Adsorption capacity of chars prepared from original bones is comparable to the adsorption capacity of these tire-based chars. 4. Conclusion To our knowledge, this study is the first to report the use of microwave pyrolyzed beef and pork bones for the adsorption of xylene from air. Activation of beef and pork bones with potassium carbonate prior to pyrolysis resulted in the formation of chars containing micropores in addition to meso- and macropores. The practical use of waste animal bones as input materials for microwave pyrolysis was demonstrated. A significant result is the formation of micropores in chars prepared from bones activated with potassium carbonate. These chars appear to be cheap and sustainable adsorbents capable of contributing to the reduction of xylene in the air. Declarations Declaration of Competing Interest The authors declare that they have no known competing financial interest or personal relationships that could have appeared to influence the work reported in this paper. Funding Financial support of the European Union under the REFRESH - Research Excellence For REgion Sustainability and High-tech Industries project [CZ.10.03.01/00/22_003/0000048] via the Operational Programme Just Transition is acknowledged. The research was also funded by the OP JAK project "INOVO!!!" [CZ.02.01.01/00/23_021/0008588] and the MATUR – Materials and Technologies for Sustainable Development project [CZ.02.01.01/00/22_008/0004631] supported by the Ministry of Education, Youth and Sports of the Czech Republic, and co-financed by the European Union. Experiments were performed by using Large Research Infrastructure ENREGAT [LM2018098; LM2023056] supported by the Ministry of Education, Youth and Sports of the Czech Republic. Data availability: Open research data will be available on Zenodo in the final version of the manuscript. References Jankovská Z et al (2024) Microporous carbon prepared by microwave pyrolysis of scrap tyres and the effect of K + in its structure on xylene adsorption. Carbon 216:118581 Rajabi H et al (2021) Sorption behaviour of xylene isomers on biochar from a range of feedstock. Chemosphere, 268 Xin YZ, Kamisaka Y, Shirai T (2025) Elimination of volatile organic compound by hydroxyapatites derived from waste bone biomass. J Ceram Soc Jpn 133(5):220–224 Jankovská Z et al (2024) Carbons prepared by microwave co-pyrolysis of waste scrap tyres and corn cob: Effect of cation size and charge on xylene adsorption. J Environ Chem Eng, 12(6) Cruz GJF et al (2015) A Comparative Study on Activated Carbons Derived from a Broad Range of Agro-industrial Wastes in Removal of Large-Molecular-Size Organic Pollutants in Aqueous Phase. Water Air Soil Pollution 226(11):214 Matejová L et al (2024) Microwave pyrolysis-prepared engineering carbons from corn cobs and red mombin seeds towards xylene adsorption. J Anal Appl Pyrol, 181 Kusmierek K et al (2021) Adsorption on activated carbons from end-of-life tyre pyrolysis for environmental applications. Part I. preparation of adsorbent and adsorption from gas phase. J Anal Appl Pyrol, 157 Dong N et al (2024) Preparation of CPVC-based activated carbon spheres and insight into the adsorption-desorption performance for typical volatile organic compounds. Environ Pollut, 343 Hayashi J et al (2005) Preparation and characterization of high-specific-surface-area activated carbons from K2CO3-treated waste polyurethane. J Colloid Interface Sci 281(2):437–443 Yang YX et al (2020) Surface modified and activated waste bone char for rapid and efficient VOCs adsorption. Chemosphere 256:9 Rojas-Mayorga CK et al (2013) Optimization of pyrolysis conditions and adsorption properties of bone char for fluoride removal from water. J Anal Appl Pyrol 104:10–18 Alkurdi SSA et al (2020) Effect of pyrolysis conditions on bone char characterization and its ability for arsenic and fluoride removal. Environ Pollut, 262 Shahid MK et al (2020) Effect of pyrolysis conditions on characteristics and fluoride adsorptive performance of bone char derived from bone residue. J Water Process Eng, 37 Cisneros-Ontiveros HG et al (2022) Optimization of synthesis variables and characterization of devilfish bone chars for the removal of cadmium(II) from water. Mrs Adv 7(32):997–1003 Park JH et al (2021) Removal of potentially toxic metal by biochar derived from rendered solid residue with high content of protein and bone tissue. Ecotoxicology and Environmental Safety, p 208 Vamvuka D et al (2018) Valorization of Meat and Bone Meal through pyrolysis for soil amendment or lead adsorption from wastewaters. Food Bioprod Process 109:148–157 Cascarosa E et al (2012) Sulphur removal using char and ash from meat and bone meal pyrolysis. Biomass Bioenergy 40:190–193 Zhang XY et al (2021) A mechanistic study on removal efficiency of four antibiotics by animal and plant origin precursors-derived biochars. Sci Total Environ, 772 Patel S et al (2015) Synthesis and characterisation of mesoporous bone char obtained by pyrolysis of animal bones, for environmental application. J Environ Chem Eng 3(4):2368–2377 Li YY et al (2023) Adsorption/desorption behavior of ionic dyes on sintered bone char. Mater Chem Phys, 297 Cortes LN et al (2019) Preparation of carbonaceous materials from pyrolysis of chicken bones and its application for fuchsine adsorption. Environ Sci Pollut Res 26(28):28574–28583 Dobrzynska J, Jankovska Z, Matejova L (2023) Chicken Cartilage-Derived Carbon for Efficient Xylene Removal. Int J Mol Sci, 24(13) Vastyl M et al (2022) A case study on microwave pyrolysis of waste tyres and cocoa pod husk; effect on quantity and quality of utilizable products. J Environ Chem Eng, 10(1) Jankovska Z, Peikertová P, Tokarský J, Matějová L (2025) Adsorbents prepared by pyrolysis for VOC abatement , in Research Square Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted 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. 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1","display":"","copyAsset":false,"role":"figure","size":48024,"visible":true,"origin":"","legend":"\u003cp\u003eAdsorption capacities of chars prepared from pork and beef bones, both original and activated with potassium carbonate or potassium hydroxide.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7931927/v1/745a3d0ce307906836c91e12.png"},{"id":94467291,"identity":"501e5c6b-9dec-42d2-b547-5b04ddfbef03","added_by":"auto","created_at":"2025-10-27 15:21:54","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":403922,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7931927/v1/98c4d774-eb8f-4bae-b1c4-c0e2da286454.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eAnimal bones-based chars and activated carbons for xylene adsorption\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eXylene is a typical representative of a group of aromatic compounds known as volatile organic compounds (VOCs). These toxic and carcinogenic substances pose a significant environmental and health risks [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Sources of volatile organic compounds (VOCs) are diverse, from cleaning products and cosmetics to building materials, industrial production, and forest fires, to name a few [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Both the risks and the variety of sources are the reason for serious societal interest in controlling VOC emissions and reducing the amount of VOCs in the atmosphere [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Adsorption is a highly efficient and easy-to-use method for the treatment of VOCs. Molecular sieves or aerogels are suitable for this purpose, however, chars are the most interesting in terms of low cost and the possibility of using various solid wastes (e.g. biomass[\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], scrap tyres[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], polymers [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e], animal bones[\u003cspan additionalcitationids=\"CR11 CR12 CR13 CR14 CR15 CR16 CR17 CR18 CR19\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]) as input material for production[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Chars from animal bones were studied as adsorbents of various pollutants such as heavy metals [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan additionalcitationids=\"CR15\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e], or dyes [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], but studies focusing on VOCs removal are almost lacking.\u003c/p\u003e\u003cp\u003eThis study is one of the few that focuses on the use of microwave pyrolysis of animal bones to obtain bone chars and activated bone chars as adsorbents. In the case of activation, we follow up on our earlier studies, which have already indicated that properly chosen activators contribute to better pore formation and thus improve adsorption efficiency [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. A novelty of this study is the first-ever demonstration of these chars as adsorbents of xylene from air.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"2. Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1. Raw bones and microwave pyrolysis\u003c/h2\u003e\u003cp\u003eXylene p.a. was obtained from VWR International, Inc. (Czech Republic). Beef and pork bones were obtained from Těš\u0026iacute;nsk\u0026eacute; jatky, s.r.o. (Czech Republic).\u003c/p\u003e\u003cp\u003eA microwave power of 200 W was used in this study. Microwave pyrolyzed samples of resulting chars were washed with weak acid, then with distilled water, and finally dried overnight. To enhance formation of pores, the beef and pork bones were also activated with potassium carbonate or potassium hydroxide, immersed in strong acid, then washed with distilled water and dried overnight. Activated bones were then pyrolyzed under the same conditions as the original bones.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e2.2. Xylene adsorption\u003c/h2\u003e\u003cp\u003eAdsorption experiments in this study were performed under the same conditions as the xylene adsorption described in our previous papers [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Xylene was adsorbed on both original (not activated) and activated chars.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003e2.3. Characterisation methods\u003c/h2\u003e\u003cp\u003eProximate analysis was performed using LECO TGA 701 analyser. Elemental analysis was performed using LECO CHNS 628 analyser. Thermogravimetric curves were determined using SDT 600 thermogravimeter in a dynamic inert atmosphere. Nitrogen physisorption was performed on Micromeritics 3Flex instrument at 77K X-ray fluorescence spectroscopy was used to semi-quantitatively determine the chemical composition. Spectro XEPOS energy dispersion spectrometer was used. Raman spectra were detected using an XploRA\u0026trade; Raman spectrometer equipped with 532 nm laser. Fourier-transform infrared (FTIR) spectra were recorded using Nicolet 6700 FT-IR spectrometer.\u003c/p\u003e\u003c/div\u003e"},{"header":"3. Results and discussion","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003e3.1. Characterization of chars\u003c/h2\u003e\u003cp\u003eAccording to the proximate analysis, nearly two times higher amount of fixed carbon was found in char from beef bones compared to char from pork bones. Char from beef bones also contained higher amount of P and Ca compared to char from pork bones. Chemical composition of activated chars allows them to be called Ca-rich chars. The Ca, C, and P content shows that the dominant phase is hydroxyapatite. According to nitrogen physisorption, original chars are mesoporous and macroporous, while activated chars also contain micropores. The specific surface area of chars from activated beef and pork bones increased\u0026thinsp;~\u0026thinsp;2\u0026times; and ~\u0026thinsp;8\u0026times;, respectively, compared to chars from original bones.\u003c/p\u003e\u003cp\u003eRaman spectroscopy of chars revealed the presence of carbon, hydroxyapatite, and calcium carbonate. The ratio of disorder band to graphitic band intensities (I\u003csub\u003eD\u003c/sub\u003e/I\u003csub\u003eG\u003c/sub\u003e) was found to be very similar for all chars. Despite this, spectra of chars from original bones show slightly lower I\u003csub\u003eD\u003c/sub\u003e/I\u003csub\u003eG\u003c/sub\u003e ratios compared to chars from activated bones, which indicates a slightly higher amount of graphitic carbon. FTIR spectra confirmed the presence of carbon, hydroxyapatite, and carbonates in the chars.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003e3.2. Adsorption of xylene onto chars\u003c/h2\u003e\u003cp\u003eThe highest adsorption capacity was shown by char prepared from pork bones activated with potassium carbonate (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Using the same activator in the case of beef bones resulted in approximately one-third the adsorption capacity compared to the previous sample. Potassium hydroxide did not prove to be a suitable activator compared to carbonate. In the case of char prepared from original beef bones, about six times the adsorption capacity was achieved compared to char prepared from original pork bones, which was the least effective adsorbent of all the samples studied (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eLiterature search shows that chars prepared from activated bones exhibits higher adsorption capacity compared to chars obtained from waste tires [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Adsorption capacity of chars prepared from original bones is comparable to the adsorption capacity of these tire-based chars.\u003c/p\u003e\u003c/div\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eTo our knowledge, this study is the first to report the use of microwave pyrolyzed beef and pork bones for the adsorption of xylene from air. Activation of beef and pork bones with potassium carbonate prior to pyrolysis resulted in the formation of chars containing micropores in addition to meso- and macropores.\u003c/p\u003e\u003cp\u003eThe practical use of waste animal bones as input materials for microwave pyrolysis was demonstrated. A significant result is the formation of micropores in chars prepared from bones activated with potassium carbonate. These chars appear to be cheap and sustainable adsorbents capable of contributing to the reduction of xylene in the air.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003ch2\u003eDeclaration of Competing Interest\u003c/h2\u003e\u003cp\u003eThe authors declare that they have no known competing financial interest or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e\u003cp\u003eFinancial support of the European Union under the REFRESH - Research Excellence For REgion Sustainability and High-tech Industries project [CZ.10.03.01/00/22_003/0000048] via the Operational Programme Just Transition is acknowledged. The research was also funded by the OP JAK project \"INOVO!!!\" [CZ.02.01.01/00/23_021/0008588] and the MATUR \u0026ndash; Materials and Technologies for Sustainable Development project [CZ.02.01.01/00/22_008/0004631] supported by the Ministry of Education, Youth and Sports of the Czech Republic, and co-financed by the European Union. Experiments were performed by using Large Research Infrastructure ENREGAT [LM2018098; LM2023056] supported by the Ministry of Education, Youth and Sports of the Czech Republic.\u003c/p\u003e\u003ch2\u003eData availability:\u003c/h2\u003e\u003cp\u003eOpen research data will be available on Zenodo in the final version of the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eJankovsk\u0026aacute; Z et al (2024) Microporous carbon prepared by microwave pyrolysis of scrap tyres and the effect of K\u0026thinsp;+\u0026thinsp;in its structure on xylene adsorption. 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Environ Sci Pollut Res 26(28):28574\u0026ndash;28583\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDobrzynska J, Jankovska Z, Matejova L (2023) Chicken Cartilage-Derived Carbon for Efficient Xylene Removal. Int J Mol Sci, 24(13)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eVastyl M et al (2022) A case study on microwave pyrolysis of waste tyres and cocoa pod husk; effect on quantity and quality of utilizable products. J Environ Chem Eng, 10(1)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eJankovska Z, Peikertov\u0026aacute; P, Tokarsk\u0026yacute; J, Matějov\u0026aacute; L (2025) \u003cem\u003eAdsorbents prepared by pyrolysis for VOC abatement\u003c/em\u003e, in \u003cem\u003eResearch Square\u003c/em\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"VSB-Technical University of Ostrava","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":"animal bones, char, xylene, microwave, activation, adsorption","lastPublishedDoi":"10.21203/rs.3.rs-7931927/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7931927/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBeef and pork waste bones, both original and activated, were microwave pyrolyzed to obtain chars usable as adsorbents of xylene from air. Bone activation with potassium carbonate or potassium hydroxide has been tested to increase adsorption efficiency by inducing micropore formation and increasing surface area. Composition and structure of the resulting chars were analyzed by a wide range of methods: proximate and elemental analyses, thermogravimetry, nitrogen physisorption, X-ray fluorescence spectroscopy, Raman spectroscopy, and Fourier-transform infrared spectroscopy. The results demonstrate that the well-developed porous structure including micropores positively affects the adsorption of xylene. Beef and pork waste bones activated with potassium carbonate were proved to be a useful input material for the preparation of cheap and sustainable adsorbents of xylene from air.\u003c/p\u003e","manuscriptTitle":"Animal bones-based chars and activated carbons for xylene adsorption","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-27 11:30:18","doi":"10.21203/rs.3.rs-7931927/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":"3e14bcf3-f642-449d-a76d-d7e90ffa58d8","owner":[],"postedDate":"October 27th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":56770239,"name":"Environmental Engineering"}],"tags":[],"updatedAt":"2025-10-27T11:30:19+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-27 11:30:18","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7931927","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7931927","identity":"rs-7931927","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}