Abstract
To date,the primary industrial carbon capture approach is still absorption using aqueous solutions of alkanolamines.Here,to pursue a substitute for the amine-based approach to improve the CO2 capture efficiency and decrease the energy cost further,we report a new carbon capture approach using a 2-methylimidazole(mIm)aqueous solution.The properties and sorption behaviors of this approach have been experimentally investigated.The results show that the mIm solution has higher CO2 absorption capacity under relatively higher equilibrium pressure(＞130 kPa)and lower desorption heat than the methyldiethanolamine solution.91.6％sorption capacity of mIm solution can be recovered at 353.15 K and 80 kPa.The selectivity for CO2/N2 and CO2/CH4 can reach an exceptional 7609 and 4324,respectively.Furthermore,the pilot-scale tests were also performed,and the results demonstrate that more than 98％of CO2 in the feed gas could be removed and cyclic absorption capacity can reach 1 mol·L-1.This work indicates that mIm is an excellent alternative to alkanolamines for carbon capture in the industry.
万方数据