H₂S Removal and CO₂/CH₄Separation of Ternary Mixtures Using Polyimide Hollow Fiber Membrane

Abstract

− In this study, by using the polymeric membrane separation process, the CO 2 /CH 4 separation and H 2 S removal from biogas were performed in order to CH 4 purification and enrichment for the fuel cell energy source application. Fibers were spun by dry/wet phase inversion method. The module was manufactured by fabricating fibers after surface coating with silicone elastomer. The scanning electron microscopy(SEM) studies showed that the produced fibers typically had an asymmetric structure; a dense top layer supported by a porous, sponge substructure. The permeance of CO 2 and CO 2 /CH 4 selectivity increased with pressure and temperature. Mixture gas with increasing pressure and temperature, removal efficiency of the CO 2 and H 2 S were decreased while concentration of CH 4 was increased up to 100%. When retentate flow rate was increased with the decreasing of pressure and temperature the CH 4 recovery ratio in retentate side was increased while the CH 4 purity in retentate side was decreased.