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⁻¹). 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.