CO2 capture by dry alkanolamines and an efficient microwave regeneration process

Abstract

Removal of acidic gases such as H₂S and CO₂ is performed during the purification of raw natural gas, most commonly using amine gas treatment. However, this industrially entrenched method is limited by significant shortcomings including low operational capture efficiency, amine pipeline corrosion and a large energy penalty due to the sorbent regeneration process. To address these shortcomings, we have studied the use of perfluorinated silica-stabilized dry alkanolamines (DA_f) for CO₂ capture. Due to their micronized liquid domains, DA_f display high operational CO₂ capture efficiency. Further, to minimize energy requirements for sorbent regeneration, microwave-assisted regeneration of the spent DA_f sorbent was also studied and shown to decrease the energy requirements by about ten times. In contrast to very recent work, our results show that the use of DA_f exhibits extraordinary recyclability, with a negligible decrease in absorption capacity over at least ten absorption–regeneration cycles, indicating the potential of this material for gas treatment applications.