Polyurethane/polyethersulfone dual-layer anisotropic membranes for CO2 removal from flue gas

摘要

Removing CO2 from flue gas streams has been a permanent challenge regarding environmental issues. Membrane technology is a solution for this problem but more efficient membranes are required. The fabrication of dual-layer polyurethane/polyethersulfone membrane by the co-casting technique is undertaken and the effects of previous evaporation time and coagulation water bath temperature on membrane morphology are explored. Uniform layers with excellent adhesion are obtained. The effect of feed pressure and temperature on membrane permeability and selectivity for CO2, N-2, and O-2 are studied. Increasing the pressure from 1 to 8 bar results in a reduction of CO2 permeability and CO2/N-2 ideal selectivity from 19.6 to 13.0 barrer, and from 66 to 60, respectively. Temperature in the range of 25-45 degrees C enhances CO2 permeability from 19.6 to 28.9 barrer, although CO2/N-2 selectivity decreases from 66 to 43, yet showing good potential for applications.