Amino acids to reduce the escape of organic amines in the CO2 capture process

Abstract

Carbon neutrality and carbon peaking are important strategic policies for our country. Carbon dioxide capture technology is the bottom of the realization of this strategy, in which amine escape is an important issue for the development of this technology. Herein, the proposal to utilize amino acids for reducing volatilization of organic amines was introduced for the first time. Diethylaminoethanol (DEEA), widely applied and highly volatile, was selected as the primary target for volatility reduction, while hydroxyethyl ethylenediamine (AEEA) and piperazine (PZ) were chosen as the main absorbents for absorption and desorption processes. The effects of DEEA addition on the main absorbent, different types of amino acid additives on volatility, and amino acids on absorption and desorption performance were investigated, respectively. Glutamine (Tyr) demonstrated significant potential in reducing the volatilization of organic amines; when 2% Tyr was added during gas–liquid equilibrium experiments, it resulted in a 74.5% decrease in DEEA volatilization within the absorbent system. Simulated gas–liquid entrainment escape showed that CO2 loading reduced volatilization by 42.31%, with a further reduction of 53.93% achieved when loaded with 0.5 molCO2/mol amine; this loading also had a promotional effect on absorption and desorption processes. Moreover, Tyr exhibited excellent stability without generating any degradation products, thereby prolonging absorber lifespan and minimizing economic cost losses.