氨基酸类固-液相变吸收剂捕集CO2及反应-相变机制OA北大核心CSTPCD

Solid-liquid phase change absorbents based on pure amino acids have defects such as low carbon dioxide(CO2)absorption rate and poor regeneration.Therefore,potassium alanine(K-Ala)which has good comprehensive performance of CO2 absorption loading and precipitation capacity was used as the main component.Piperazine(PZ)which is resistant to degradation and has high reactivity was used as the activator,while n-propanol(NPA)which promotes the formation of solid phase products was used as the solvent.A novel solid-liquid phase change CO2 absorption system K-Ala+PZ+NPA+H2O was constructed,and CO2 capture performance,reaction mechanism and phase change mechanism of the absorption system were studied.The saturated CO2 absorption loading of this system is 0.68 mol·mol-1,and the regeneration efficiency is 83.04%.The saturated solid phase mainly contains K-Ala carbamate(K-Ala-COO-),PZ carbamate(PZ-COO-)and bicarbonate(HCO3-).Due to the higher polarity and lower solvation free energy of the above products compared with the original components,self-polymerization between the products occurred and finally the phase separation behavior formed.