Reducing Heat Duty of MEA Regeneration Using a Sulfonic Acid-Functionalized Mesoporous MCM-41 Catalyst
Qiang Sun, Tianhao Li, Yu Mao, Hongxia Gao, Teerawat Sema, Shengyu Wang, Libing Liu, Zhiwu Liang
Abstract
Amine-based CO2 capture is a promising method to limit global CO2 emissions. However, large thermal energy consumption for CO2 desorption during amine regeneration has limited large-scale worldwide applications. Here, we show that an efficient MCM-41-SO3H-0.6 catalyst presented a superior catalytic performance, decreasing the relative heat duty by one-third and enhancing the instantaneous desorption rate by up to 195% in comparison with the monoethanolamine (MEA) regeneration without catalysts. The excellent catalytic activity is related to the combination of the properties of mesopore surface area × total acid sites, and a possible catalytic mechanism is proposed for the MCM-41-SO3H catalysts. Furthermore, the experimental results in the MEA solution regeneration process were consistent with density functional theory calculations in revealing the catalytic desorption mechanism. This work demonstrated that MCM-41 functionalized with sulfonic acid group catalysts could play an essential role in the post-combustion CO2 capture technology using aqueous MEA for industrial applications.