A high performance antioxidative and acid resistant membrane prepared by interfacial polymerization for CO2 separation from flue gas

An antioxidative composite membrane was developed by interfacial polymerization of trimesoyl chloride and sodium 3,5-diaminobenzoate on a cross-linked polydimethylsiloxane coating polysulfone membrane. Diethylene glycol bis(3-aminopropyl) ether was added into the aqueous phase to improve CO2 permeance by the CO2-philic group, namely ether oxygen. Attenuated total reflectance-Fourier transform infrared resonance spectroscopy and scanning electron microscopy were used to characterize the composite membranes. The effects of the molar ratio of monomers in the aqueous phase and the concentrations of monomers in both the aqueous phase and the organic phase were investigated to obtain higher permselectivity. For CO2/N-2 gas mixture (15/85 by volume), the optimized membrane displays a CO2 permeance of 5831 GPU and CO2/N-2 selectivity of 86 at 0.11 MPa feed pressure. Moreover, the membrane shows excellent antioxidizability and acid resistance. Finally, the economic evaluation of the membranes prepared in this work for flue gas separation was carried out. A two-stage membrane system using the membrane prepared in this work shows cost-competition compared with the traditional chemical absorption method.