Study on the performance of CO2 capture from flue gas with ceramic and PTFE membrane contactors

Abstract

Excessive CO2 emissions contribute to global warming, which may cause potential threat to survival of humans and other creatures, and it is necessary to take effective measures to curb CO2 emissions. Gas-liquid membrane contact CO2 separation technology is an emerging CO2 capture technology that combines advantages of membrane separation and chemical absorption. In this paper, differences of CO2 capture performance between ceramic and polytetrafluoroethylene (PTFE) membranes with pore size of 10 nm and 100 nm are investigated comprehensively. The morphological structure, pore size distribution, wettability and membrane flux of ceramic and PTFE membranes are analyzed by membrane characterization. Moreover, with monoethanolamine (MEA) as absorbent, CO2 capture performance under different operating parameters (e.g., absorber flow rate and temperature, gas flow rate and pressure) is investigated through experiments based on ceramic and PTFE membrane modules. The CO2 capture efficiency of ceramic and PTFE membrane is 94.7% and 99.3%, respectively. However, the mass transfer rate of ceramic membrane is much higher than that of PTFE membrane. The results show that ceramic membrane exhibits favorable CO2 capture performance under appropriate operation parameters. This paper will provide theoretical and technical references for subsequent industrial CO2 capture applications.