{"id":{"repo_id":"columbia-diss","oai_identifier":"oai:academiccommons.columbia.edu:10.7916/D8F76KPR"},"canonical_url":"https://search.dev.ndltd.org/etd/columbia-diss/oai:academiccommons.columbia.edu:10.7916/D8F76KPR","repository":{"repo_id":"columbia-diss","name":"Columbia University","base_url":"https://academiccommons.columbia.edu/oai"},"display":{"title":"Catalytic Reforming of Biogas for Syngas Production","abstract":"Biogas is a mixture of methane and carbon dioxide produced from the anaerobic microbial digestion of biomass. It is an inexpensive, local source of energy but is usually wasted because the CO₂ content dilutes the quality of the fuel. Dry and auto-thermal reforming are catalytic methods that convert both the CH₄ and CO₂ into H₂ and CO, or syngas, a valuable product that can be used to produce liquid fuels, provide H₂ for fuel cells, or improve the combustion of biogas. A Rh/Al₂O₃ catalyst is successful in dry reforming biogas to syngas without deactivation from carbon formation at CH₄/CO₂ ratios of one or lower. In CH₄ rich mixtures, auto-thermal reforming (ATR) is effective because it provides additional oxidant that eliminates carbon formation and combusts a portion of the CH4 in-situ to provide the heat needed for the endothermic reforming reactions. In addition to CH₄ and CO₂, biogas also contains chlorocarbons that are potential catalyst poisons. Chlorocarbons are unique to biogas and bio-derived fuels due to the natural presence of chlorinated compounds in organic material that are released during decomposition or thermal treatment. Despite their presence in biogas in 10-50ppm concentrations, the effect of chlorocarbons on the dry reforming reaction has not been extensively studied. This work investigated the effect of CH₃Cl in particular on the activity and selectivity of CH₄ dry and auto-thermal reforming using a Rh/Al₂O₃ catalyst. It was determined that CH₃Cl introduction into the reforming reaction deposits chloride on the alumina catalyst support, which increases the surface acidity, poisons the water-gas shift reactions by replacing basic hydroxyl groups, and poisons the dry reforming reaction by reducing hydrogen mobility and the affinity of CO₂ for the alumina support. CH3Cl also likely competes and reacts preferentially over CH₄ for dry reforming sites. In CO₂ rich environments, the reverse water gas shift reaction is poisoned, resulting in an increase of the H₂/CO ratio, while in H₂O rich environments, the forward water gas shift reaction is poisoned, resulting in a decrease of the H₂/CO ratio. With 50 ppm addition of CH₃Cl into a dry reforming reaction, the H₂/CO ratio increases by 53% at a relatively low temperature of 350°C and increases by only 3% at 700°C. The poisoning of the water gas shift and dry reforming reactions, and the resulting changes in product selectivity and dry reforming activity, are completely reversible upon removal of CH₃Cl from the feed. Therefore, the amount of chlorocarbon expected in a biogas mixture, between 10-50ppm, is not particularly harmful for the 4% Rh/Al2O3 catalyst. The degree of chloride poisoning is directly proportional to CH3Cl concentration and inversely proportional to H₂O concentration and temperature. Therefore, O₂ or air co-feeding minimizes chloride poisoning because it produces H₂O and additional heat from the CH4 combustion reaction, both of which decrease chloride poisoning. Auto-thermal reforming is therefore more effective than dry reforming biogas because it keeps the Rh/Al2O3 catalyst clean of carbon and chloride deposition, thereby maintaining the activity and selectivity of the catalyst for conversion of biogas into syngas.","abstract_html":"Biogas is a mixture of methane and carbon dioxide produced from the anaerobic microbial digestion of biomass. It is an inexpensive, local source of energy but is usually wasted because the CO₂ content dilutes the quality of the fuel. Dry and auto-thermal reforming are catalytic methods that convert both the CH₄ and CO₂ into H₂ and CO, or syngas, a valuable product that can be used to produce liquid fuels, provide H₂ for fuel cells, or improve the combustion of biogas. A Rh/Al₂O₃ catalyst is successful in dry reforming biogas to syngas without deactivation from carbon formation at CH₄/CO₂ ratios of one or lower. In CH₄ rich mixtures, auto-thermal reforming (ATR) is effective because it provides additional oxidant that eliminates carbon formation and combusts a portion of the CH4 in-situ to provide the heat needed for the endothermic reforming reactions. In addition to CH₄ and CO₂, biogas also contains chlorocarbons that are potential catalyst poisons. Chlorocarbons are unique to biogas and bio-derived fuels due to the natural presence of chlorinated compounds in organic material that are released during decomposition or thermal treatment. Despite their presence in biogas in 10-50ppm concentrations, the effect of chlorocarbons on the dry reforming reaction has not been extensively studied. This work investigated the effect of CH₃Cl in particular on the activity and selectivity of CH₄ dry and auto-thermal reforming using a Rh/Al₂O₃ catalyst. It was determined that CH₃Cl introduction into the reforming reaction deposits chloride on the alumina catalyst support, which increases the surface acidity, poisons the water-gas shift reactions by replacing basic hydroxyl groups, and poisons the dry reforming reaction by reducing hydrogen mobility and the affinity of CO₂ for the alumina support. CH3Cl also likely competes and reacts preferentially over CH₄ for dry reforming sites. In CO₂ rich environments, the reverse water gas shift reaction is poisoned, resulting in an increase of the H₂/CO ratio, while in H₂O rich environments, the forward water gas shift reaction is poisoned, resulting in a decrease of the H₂/CO ratio. With 50 ppm addition of CH₃Cl into a dry reforming reaction, the H₂/CO ratio increases by 53% at a relatively low temperature of 350°C and increases by only 3% at 700°C. The poisoning of the water gas shift and dry reforming reactions, and the resulting changes in product selectivity and dry reforming activity, are completely reversible upon removal of CH₃Cl from the feed. Therefore, the amount of chlorocarbon expected in a biogas mixture, between 10-50ppm, is not particularly harmful for the 4% Rh/Al2O3 catalyst. The degree of chloride poisoning is directly proportional to CH3Cl concentration and inversely proportional to H₂O concentration and temperature. Therefore, O₂ or air co-feeding minimizes chloride poisoning because it produces H₂O and additional heat from the CH4 combustion reaction, both of which decrease chloride poisoning. Auto-thermal reforming is therefore more effective than dry reforming biogas because it keeps the Rh/Al2O3 catalyst clean of carbon and chloride deposition, thereby maintaining the activity and selectivity of the catalyst for conversion of biogas into syngas.","abstract_has_math":false,"creators":["Kohn, McKenzie Primerano"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2012,"date_issued":"2012","date_published":"2012","updated_at":"2026-07-24T01:44:22Z","subjects":["Chemical engineering","Environmental engineering","Biogas","Synthesis gas","Catalytic reforming","Methane","Carbon dioxide","Aluminum oxide","Methyl chloride","Chlorides--Environmental aspects"],"languages":["English"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://doi.org/10.7916/D8F76KPR","outbound_label":"DOI","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Kohn, McKenzie Primerano"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2012"]},{"key":"dc:type","label":"Dc Type","values":["Theses"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Chemical engineering","Environmental engineering","Biogas","Synthesis gas","Catalytic reforming","Methane","Carbon dioxide","Aluminum oxide","Methyl chloride","Chlorides--Environmental aspects"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["English"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://doi.org/10.7916/D8F76KPR"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Biogas is a mixture of methane and carbon dioxide produced from the anaerobic microbial digestion of biomass. It is an inexpensive, local source of energy but is usually wasted because the CO₂ content dilutes the quality of the fuel. Dry and auto-thermal reforming are catalytic methods that convert both the CH₄ and CO₂ into H₂ and CO, or syngas, a valuable product that can be used to produce liquid fuels, provide H₂ for fuel cells, or improve the combustion of biogas. A Rh/Al₂O₃ catalyst is successful in dry reforming biogas to syngas without deactivation from carbon formation at CH₄/CO₂ ratios of one or lower. In CH₄ rich mixtures, auto-thermal reforming (ATR) is effective because it provides additional oxidant that eliminates carbon formation and combusts a portion of the CH4 in-situ to provide the heat needed for the endothermic reforming reactions. In addition to CH₄ and CO₂, biogas also contains chlorocarbons that are potential catalyst poisons. Chlorocarbons are unique to biogas and bio-derived fuels due to the natural presence of chlorinated compounds in organic material that are released during decomposition or thermal treatment. Despite their presence in biogas in 10-50ppm concentrations, the effect of chlorocarbons on the dry reforming reaction has not been extensively studied. This work investigated the effect of CH₃Cl in particular on the activity and selectivity of CH₄ dry and auto-thermal reforming using a Rh/Al₂O₃ catalyst. It was determined that CH₃Cl introduction into the reforming reaction deposits chloride on the alumina catalyst support, which increases the surface acidity, poisons the water-gas shift reactions by replacing basic hydroxyl groups, and poisons the dry reforming reaction by reducing hydrogen mobility and the affinity of CO₂ for the alumina support. CH3Cl also likely competes and reacts preferentially over CH₄ for dry reforming sites. In CO₂ rich environments, the reverse water gas shift reaction is poisoned, resulting in an increase of the H₂/CO ratio, while in H₂O rich environments, the forward water gas shift reaction is poisoned, resulting in a decrease of the H₂/CO ratio. With 50 ppm addition of CH₃Cl into a dry reforming reaction, the H₂/CO ratio increases by 53% at a relatively low temperature of 350°C and increases by only 3% at 700°C. The poisoning of the water gas shift and dry reforming reactions, and the resulting changes in product selectivity and dry reforming activity, are completely reversible upon removal of CH₃Cl from the feed. Therefore, the amount of chlorocarbon expected in a biogas mixture, between 10-50ppm, is not particularly harmful for the 4% Rh/Al2O3 catalyst. The degree of chloride poisoning is directly proportional to CH3Cl concentration and inversely proportional to H₂O concentration and temperature. Therefore, O₂ or air co-feeding minimizes chloride poisoning because it produces H₂O and additional heat from the CH4 combustion reaction, both of which decrease chloride poisoning. Auto-thermal reforming is therefore more effective than dry reforming biogas because it keeps the Rh/Al2O3 catalyst clean of carbon and chloride deposition, thereby maintaining the activity and selectivity of the catalyst for conversion of biogas into syngas."]},{"key":"dc:title","label":"Title","values":["Catalytic Reforming of Biogas for Syngas Production"]}]}],"canonical_facts":{"dc:creator":["Kohn, McKenzie Primerano"],"dc:date":["2012"],"dc:description":["Biogas is a mixture of methane and carbon dioxide produced from the anaerobic microbial digestion of biomass. It is an inexpensive, local source of energy but is usually wasted because the CO₂ content dilutes the quality of the fuel. Dry and auto-thermal reforming are catalytic methods that convert both the CH₄ and CO₂ into H₂ and CO, or syngas, a valuable product that can be used to produce liquid fuels, provide H₂ for fuel cells, or improve the combustion of biogas. A Rh/Al₂O₃ catalyst is successful in dry reforming biogas to syngas without deactivation from carbon formation at CH₄/CO₂ ratios of one or lower. In CH₄ rich mixtures, auto-thermal reforming (ATR) is effective because it provides additional oxidant that eliminates carbon formation and combusts a portion of the CH4 in-situ to provide the heat needed for the endothermic reforming reactions. In addition to CH₄ and CO₂, biogas also contains chlorocarbons that are potential catalyst poisons. Chlorocarbons are unique to biogas and bio-derived fuels due to the natural presence of chlorinated compounds in organic material that are released during decomposition or thermal treatment. Despite their presence in biogas in 10-50ppm concentrations, the effect of chlorocarbons on the dry reforming reaction has not been extensively studied. This work investigated the effect of CH₃Cl in particular on the activity and selectivity of CH₄ dry and auto-thermal reforming using a Rh/Al₂O₃ catalyst. It was determined that CH₃Cl introduction into the reforming reaction deposits chloride on the alumina catalyst support, which increases the surface acidity, poisons the water-gas shift reactions by replacing basic hydroxyl groups, and poisons the dry reforming reaction by reducing hydrogen mobility and the affinity of CO₂ for the alumina support. CH3Cl also likely competes and reacts preferentially over CH₄ for dry reforming sites. In CO₂ rich environments, the reverse water gas shift reaction is poisoned, resulting in an increase of the H₂/CO ratio, while in H₂O rich environments, the forward water gas shift reaction is poisoned, resulting in a decrease of the H₂/CO ratio. With 50 ppm addition of CH₃Cl into a dry reforming reaction, the H₂/CO ratio increases by 53% at a relatively low temperature of 350°C and increases by only 3% at 700°C. The poisoning of the water gas shift and dry reforming reactions, and the resulting changes in product selectivity and dry reforming activity, are completely reversible upon removal of CH₃Cl from the feed. Therefore, the amount of chlorocarbon expected in a biogas mixture, between 10-50ppm, is not particularly harmful for the 4% Rh/Al2O3 catalyst. The degree of chloride poisoning is directly proportional to CH3Cl concentration and inversely proportional to H₂O concentration and temperature. Therefore, O₂ or air co-feeding minimizes chloride poisoning because it produces H₂O and additional heat from the CH4 combustion reaction, both of which decrease chloride poisoning. Auto-thermal reforming is therefore more effective than dry reforming biogas because it keeps the Rh/Al2O3 catalyst clean of carbon and chloride deposition, thereby maintaining the activity and selectivity of the catalyst for conversion of biogas into syngas."],"dc:identifier":["https://doi.org/10.7916/D8F76KPR"],"dc:language":["English"],"dc:subject":["Chemical engineering","Environmental engineering","Biogas","Synthesis gas","Catalytic reforming","Methane","Carbon dioxide","Aluminum oxide","Methyl chloride","Chlorides--Environmental aspects"],"dc:title":["Catalytic Reforming of Biogas for Syngas Production"],"dc:type":["Theses"]},"updated_at":"2026-07-24T01:44:22Z"}