SEPARATION OF CARBON DIOXIDE (CO2) FROM GAS MIXTURES BY CALCIUM BASED REACTION SEPARATION (CARS-CO2) PROCESS

摘要

Carbon dioxide is selectively removed from a gas mixture to provide a gaseous stream depleted in CO sub 2 compared to the inlet stream The CO sub 2 is separated from a gas mixture (e g flue gas/fuel gas) by its reaction with metal oxides (such as calcium oxide) Calcium-based reaction separation for CO sub 2 (CaRS-CO sub 2) consists of contacting a CO sub 2 laden gas with calcium oxide (CaO) in a reactor such that CaO captures the CO sub 2 by the formation of calcium carbonate (CaCO sub 3) Once "spent", CaCO sub 3 is regenerated by its calcination leading to the formation of fresh CaO sorbent and the evolution of a concentrated stream of CO sub 2 The "regenerated" CaO is then recycled for the further capture of more CO sub 2 A mesoporous CaCO sub 3 structure that attains >90% conversion over multiple carbonation and calcination cycles is identified Thermal regeneration (calcination) under vacuum proves a sorbent structure that maintains reproducible reactivity levels over multiple cycles