Molecular Sieve Carbon Membrane from Lignin-based Materials

Abstract

Carbon membranes were prepared by coating thin layers of lignocresol derived from lignin by the phase-separation method and then carbonizing the lignocresol at 673?1073K by high frequency induction heating or conventional tube reactors. The thickness of the membrane formed on the outer surface of a porous alumina substrate was about 400-1000 nm judging from SEM observation. The activation energy for gas permeation through the membranes increased with increasing molecular diameter of the penetrant gas, indicating activated diffusion process. The permeation properties were dependent on heating conditions. It can be concluded that carbon membranes derived from lignin-based materials provide one of the promising candidates for high performance membrane.