Performance of a new water lean absorbent composed of EHA and DEGDEE in CO2 capture and regeneration

Previous work has shown that non-aqueous absorbent composed of dimethyl sulfoxide (DMSO) and 2-ethylhexylan-1-amine (EHA) is superior to commercial monoethanolamine (MEA) in both absorption of CO 2 and desorption. However, the price of DMSO is too high, which leads to the high cost of reagents. It is worthwhile to choose a cheap solvent instead of DMSO, which can also achieve satisfactory absorption and desorption performance. Around this goal, we selected diethylene glycol diethyl ether (DEGDEE) to form a non-aqueous absorbent with EHA and investigated the absorption and desorption performance. The desorption efficiency of 70 wt% EHA +30 wt% DEGDEE was 99 % at 373 K. The desorption efficiency was 89.4 %, and the desorption energy consumption was only 45.1 % of MEA when the water content was 10 wt%. DEGDEE can achieve similar or even better performance than DMSO, while the cost of DEGDEE (12000–31000 RMB/ton, technical grade purity 99 %) is lower than DMSO (40000–48000 RMB/ton, technical grade purity 99 %). In addition, it also has a good recycling capacity. These advantages will certainly endow this newly developed absorbent with great application prospects in the field of CO 2 capture.