Metal Oxyhydroxide Catalysts Promoted CO2 Absorption and Desorption in Amine-Based Carbon Capture: A Feasibility Study

Long Ji; Jiabi Li; Rongrong Zhai; Jinyi Wang; Xiaolong Wang; Shuiping Yan; Ming Hua

doi:10.1021/acsomega.2c02851

Metal Oxyhydroxide Catalysts Promoted CO₂ Absorption and Desorption in Amine-Based Carbon Capture: A Feasibility Study

ACS Omega. 2022 Nov 29;7(49):44620-44630. doi: 10.1021/acsomega.2c02851. eCollection 2022 Dec 13.

Authors

Long Ji^{1

2}, Jiabi Li¹, Rongrong Zhai³, Jinyi Wang⁴, Xiaolong Wang⁴, Shuiping Yan², Ming Hua¹

Affiliations

¹ State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
² College of Engineering, Huazhong Agricultural University, Wuhan 430070, China.
³ School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China.
⁴ Huaneng Clean Energy Research Institute, Beijing 102209, China.

Abstract

The huge energy penalty of CO₂ desorption is the greatest challenge impeding the commercial application of amine-based CO₂ capture. To deal with this problem, a series of metal oxide and oxyhydroxide catalysts were synthesized in this study to kinetically facilitate the CO₂ desorption from 5.0 M monoethanolamine (MEA). The effects of selected catalysts on CO₂ absorption kinetics, CO₂ absorption capacity, CO₂ reaction enthalpy, and desorption duty reduction of 2.0 M MEA were investigated by a true heat flow reaction calorimeter to access the practical feasibility of the catalytic CO₂ desorption. The kinetic study of catalytic CO₂ desorption was also carried out. CO₂ desorption chemistry, catalyst characterization, and structure-function relationships were investigated to reveal the underlying mechanisms. Results show that addition of the catalyst had slight effects on the CO₂ absorption kinetics and CO₂ reaction enthalpy of MEA. In contrast, the CO₂ desorption efficiency greatly increased from 28% in reference MEA to 52% in ZrO(OH)₂-aided MEA. Compared to the benchmark catalyst HZSM-5, ZrO(OH)₂ exhibited a 13% improvement in CO₂ desorption efficiency. More importantly, compared to the reference MEA, the CO₂ desorption duties of ZrO(OH)₂ and FeOOH-aided MEA significantly reduced by 45 and 47% respectively, which are better than those of most other reported catalysts. The large surface area, pore volume, pore diameter, and amount of surface hydroxyl groups of ZrO(OH)₂ and FeOOH afforded the catalytic performance by promoting the adsorption of alkaline speciation (e.g., MEA and HCO₃ ^-) onto the particle surface.