Abstract: A reaction-based process developed for the selective removal of CO2 from a multicomponent gas mixture to provide a gaseous stream depleted in CO2 compared to the inlet CO2 concentration. The proposed process effects the separation of CO2 from a mixture of gases by its reaction with metal oxides. The Calcium based Reaction Separation for CO2 (CaRS-CO2) process consists of contacting CO2 laden gas with CaO in a reactor such that CaO captures CO2 by the formation of CaCO3. CaCO3 is regenerated by calcination leading to the formation of fresh CaO sorbent and the evolution of a concentrated stream of CO2. The “regenerated” CaO is then recycled for the further capture of CO2. This carbonation-calcination cycle forms the basis of the CaRS-CO2 process. This process also may use a mesoporous CaCO3 structure that attains >90% conversion over multiple carbonation and calcination cycles.

Abstract: A reaction-based process developed for the selective removal of CO2 from a multicomponent gas mixture to provide a gaseous stream depleted in CO2 compared to the inlet CO2 concentration. The proposed process effects the separation of CO2 from a mixture of gases by its reaction with metal oxides. The Calcium based Reaction Separation for CO2 (CaRS-CO2) process consists of contacting CO2 laden gas with CaO in a reactor such that CaO captures CO2 by the formation of CaCO3. CaCO3 is regenerated by calcination leading to the formation of fresh CaO sorbent and the evolution of a concentrated stream of CO2. The “regenerated” CaO is then recycled for the further capture of CO2. This carbonation-calcination cycle forms the basis of the CaRS-CO2 process. This process also may use a mesoporous CaCO3 structure that attains >90% conversion over multiple carbonation and calcination cycles.

Abstract: A reaction-based process has been developed for the selective removal of carbon dioxide (CO2) from a multicomponent gas mixture to provide a gaseous stream depleted in CO2 compared to the inlet CO2 concentration in the stream. The proposed process effects the separation of CO2 from a mixture of gases (such as flue gas/fuel gas) by its reaction with metal oxides (such as calcium oxide). The Calcium based Reaction Separation for CO2 (CaRS—CO2) process consists of contacting a CO2 laden gas with calcium oxide (CaO) in a reactor such that CaO captures the CO2 by the formation of calcium carbonate (CaCOa). Once “spent”, CaCO3 is regenerated by its calcination leading to the formation of fresh CaO sorbent and the evolution of a concentrated stream of CO2. The “regenerated” CaO is then recycled for the further capture of more CO2. This carbonation-calcination cycle forms the basis of the CaRS—CO2 process.

Abstract: A process for producing hydrogen, comprising the steps of: (a) gasifying a fuel into a raw synthesis gas comprising CO, hydrogen, steam and sulfur and halide contaminants in the form of H2S, COS and HX, where X is a halide; (b) passing the raw synthesis gas through a water gas shift reactor (WGSR) into which CaO and steam are injected, the CaO reacting with the shifted gas to remove CO2, sulfur and halides in a solid-phase calcium-containing product comprising CaCO3, CaS and CaX2; (c) separating the solid-phase calcium-containing product from an enriched gaseous hydrogen product; and (d) regenerating the CaO by calcining the solid-phase calcium-containing product at a condition selected from the group consisting of: in the presence of steam, in the presence of CO2, in the presence of synthesis gas, in the presence of H2 and O2, under partial vacuum, and combinations thereof. The CaO may have a surface area of at least 12.0 m2/g and a pore volume of at least 0.

Abstract: Applying an acid treatment to eggshells provides a sorbent with unexpectedly high CO2 capture capacity and ability to regenerate.

Abstract: A reaction-based process has been developed for the selective removal of carbon dioxide from a multicomponent gas mixture. The proposed process effects the separation of CO2 from a mixture of gases by its reaction with metal oxides. The Calcium based Reaction Separation for CO2 process consists of contacting a CO2 laden gas with calcium oxide in a reactor such that CaO captures the CO2 by the formation of calcium carbonate. Once “spent”, CaCO3 is regenerated by its calcination leading to the formation of fresh CaO sorbent. The “regenerated” CaO is then recycled for the further capture of more CO2. This process also identifies the application of a mesoporous CaCO3 structure, that attains >90% conversion over multiple carbonation and calcination cycles. Lastly, thermal regeneration (calcination) under vacuum provided a better sorbent structure that maintained reproducible reactivity levels over multiple cycles.

Abstract: A process for producing hydrogen, comprising the steps of: (a) gasifying a fuel into a raw synthesis gas comprising CO, hydrogen, steam and sulfur and halide contaminants in the form of H2S, COS and HX, where X is a halide; (b) passing the raw synthesis gas through a water gas shift reactor (WGSR) into which CaO and steam are injected, the CaO reacting with the shifted gas to remove CO2, sulfur and halides in a solid-phase calcium-containing product comprising CaCO3, CaS and CaX2; (c) separating the solid-phase calcium-containing product from an enriched gaseous hydrogen product; and (d) regenerating the CaO by calcining the solid-phase calcium-containing product at a condition selected from the group consisting of: in the presence of steam, in the presence of CO2, in the presence of synthesis gas, in the presence of H2 and O2, under partial vacuum, and combinations thereof. The CaO may have a surface area of at least 12.0 m2/g and a pore volume of at least 0.

Abstract: A reaction-based process has been developed for the selective removal of carbon dioxide (CO2) from a multicomponent gas mixture to provide a gaseous stream depleted in CO2 compared to the inlet CO2 concentration in the stream. The proposed process effects the separation of CO2 from a mixture of gases (such as flue gas/fuel gas) by its reaction with metal oxides (such as calcium oxide). The Calcium based Reaction Separation for CO2 (CaRS—CO2) process consists of contacting a CO2 laden gas with calcium oxide (CaO) in a reactor such that CaO captures the CO2 by the formation of calcium carbonate (CaCOa). Once “spent”, CaCO3 is regenerated by its calcination leading to the formation of fresh CaO sorbent and the evolution of a concentrated stream of CO2. The “regenerated” CaO is then recycled for the further capture of more CO2. This carbonation-calcination cycle forms the basis of the CaRS—CO2 process.