Study on the improvement of the carbonation characteristics of Ca-based CO_2 absorbent by steam repetitive calcination-carbonation

Repetitive calcination-carbonation of Ca-based CO2 absorbent with adding steam was performed experimentally to investigate the effect of steam on the cyclic characteristics of Ca-based CO2 absorbent.The maximum conversion rate,pore radius and specific surface area microstructure of hydrated Ca-based CO2 absorbent was analyzed.Results showed that the cyclic characteristics of the hydrated Ca-based CO2 absorbent was improved,the maximum conversion of Ca-based CO2 absorbent was increased by 50% than dry ones.The reason was that the steam treatment could greatly increase the specific surface area of the absorbent and improve the distributions of pore radius.From the experiment we can conclude that direct hydrogen production by carbon energy could be realized without any additives or auxiliary conditions,which would meatain the cyclic activity of Ca-based CO2 absorbent.