2-Hydroxypropyl-diethylenetriamine (HPDETA)-based nonaqueous absorbents for energy-efficient CO2 capture with high stability and low corrosivity

Nonaqueous amine absorbents have received considerable attention currently due to their energy efficiency and noncorrosiveness for CO2 capture. In this study, the new nonaqueous amine absorbents were developed by dissolving 2-hydroxypropyl-diethylenetriamine (HPDETA) in various organic solvents. The experimental results demonstrated that the obtained HPDETA-based nonaqueous amine absorbents have improved efficiency for CO2 capture compared to HPDETA in H2O, especially in terms of CO2 cyclic capability, reusability, and thermal stability. Moreover, the regeneration energy consumption of the optimal nonaqueous amine absorbent, HPDETA in diethylene glycol (HPDETA/DEG), can be reduced to as low as 2.00 GJ center dot t(-1) CO2. Importantly, HPDETA/DEG demonstrated near noncorrosiveness to 20# carbon steel during CO2 capture, which is significantly superior to that of DETA and HPDETA in H2O. Overall, the HPDETA-based nonaqueous amine absorbents will be the promising candidates for practical CO2 capture application.