SOLVENT-SWOLLEN MEMBRANES FOR THE REMOVAL OF H(2)S AND CO(2) FROM COAL GASES

ACID GAS REMOVAL BY CONVENTIONAL ABSORPTION PRODESSES IS AN EXPENSIVE STEP IN THE PRODUCTION OF CLEAN FUELS FROM BOTH LOW- AND HIGH-BTU COAL GASES. MEMBRANE PROCESSES FOR ACID GAS SCRUBBING ARE COMPARATIVELY SIMPLE AND ECONOMICAL. HOWEVER, CONVENTIONAL POLYMERIC MEMBRANES LACK THE REQUIRED PERMEABILITY AND SELECTIVITY. IMMOBILIZED LIQUID MEMBRANES ARE MUCH MORE PERMEABLE AND SELECTIVE, BUT THEY CANNOT WITHSTAND THE LARGE PRESSURE DIFFERENCES ASSOCIATED WITH COAL GAS PURIFICATION. A NOVEL MEMBRANE MATERIALS CONCEPT WILL BE PURSUED IN THIS PROGRAM. THE THIN-FILM-COMPOSITE MEMBRANE WE PROPOSE TO DEVELOP CONSISTS OF A POLYMER SWOLLENWITH A HIGH CONCENTRATION OF AN ACID-GAS-ABSORBING SOLVENT. IT PROMISES TO COMBINE THE HIGH THROUGHPUT AND SELECTIVITY CHARACTERISTIC OF LIQUID MEMBRANES WITH THE PRESSURE CAPABILITY OF POLYMERIC FILMS.