Catalytic carbon dioxide absorption and stripping using nanofibrous membrane contactors

Abstract

Catalyst-assisted CO₂ capture processes are developed using membrane gas-solvent contactors. While chemical absorption-based capture methods are among the most practical for CO₂ capture, they are generally regarded as energy-intensive, particularly for the regeneration of CO₂-rich solvents. Herein, we propose catalytic membrane-based CO₂ absorption and desorption processes which significantly lower the solvent regeneration temperature and offer additional CO₂ sorption sites within mesoporous MCM-41 based catalysts. The incorporation of membrane gas-solvent contactors with hydrophobic polymer nanofibres enhances CO₂ transfer by creating a larger mass transfer area. The resulting catalytic CO₂ capture process, incorporating 1.0 wt% of SO₄^2-/MCM-41 nanocatalysts in 5 M monoethanolamine (MEA) solution and Thermally Rearranged polymer (TR-PBOI) nanofibre membranes, demonstrates 23.5mmol m⁻² s⁻¹ of CO₂ absorption flux at 50 °C and 32.6mmol m⁻² s⁻¹ of CO₂ desorption flux at 90 °C, presenting a catalytic enhancement of 150 %.