The study of CO₂ absorption intensification using porous media material in aqueous AMP solution

In this work, the performance of CO₂ absorption into aqueous 2-amino-2-methyl-propanol (AMP) solution was investigated by measuring the amount of CO₂ in the liquid phase during CO₂ absorption process to identify initial CO₂ absorption rate. Then, the porous media material named as MCM41 was introduced into the amine solution to test its influence on CO₂ absorption. It was found that MCM41 increased initial CO₂ absorption rate and enhanced CO₂ absorption process. The physico-chemical properties of MCM41 were characterized in terms of specific surface area, average pore diameter, total pore volume and chemical properties, the amount of acidic sites and the Brϕnsted/Lewis (B/L) acid sites ratio. Results showed that MCM41 was a type of Lewis acid catalyst with large specific surface area and pore volume. In addition, the pKa of AMP solution with and without MCM41 was obtained using acid titration technology to help understand the effect brought by MCM41. A mechanism illustrating how MCM41 increases the CO₂ absorption rate of the AMP solution was proposed and demonstrated that MCM41 is a potential material for enhancing CO₂ absorption.