An integrated technology for the absorption and utilization of CO2 in alkanolamine solution for the preparation of BaCO3 in a high-gravity environment

Abstract

In this study, an integrated technology is proposed for the absorption and utilization of CO2 in alkanolamine solution for the preparation of BaCO3 in a high gravity environment. The effects of absorbent type, high gravity factor, gas/liquid ratio, and initial BaCl2 concentration on the absorption rate and amount of CO2 and the preparation of BaCO3 are investigated. The results reveal that the absorption rate and amount of CO2 follow the order of ethyl alkanolamine (MEA) > diethanol amine (DEA) > N-methyldiethanolamine (MDEA), and thus MEA is the most effective absorbent for CO2 absorption. The absorption rate and amount of CO2 under high gravity are higher than that under normal gravity. Notably, the absorption rate at 75 min under high gravity is approximately 2 times that under normal gravity. This is because the centrifugal force resulting from the high-speed rotation of the packing can greatly increase gas-liquid mass transfer and micromixing. The particle size of BaCO3 prepared in the rotating packed bed is in the range of 57.2−89 nm, which is much smaller than that prepared in the bubbling reactor (>100.3 nm), and it also has higher purity (99.6 %) and larger specific surface area (14.119 m2/g). It is concluded that the high gravity technology has the potential to increase the absorption and utilization of CO2 in alkanolamine solution for the preparation of BaCO3. This study provides new insights into carbon emissions reduction and carbon utilization.