A STUDY OF VOLATILE HYDROCARBON EMISSION CONTROL BY POLYETHERIMIDE HOLLOW-FIBER MEMBRANES

Hollow fibers were spun from a polyetherimide solution and used for th e separation of volatile organic compounds (VOC) from nitrogen. It was found that a polymer concentration of 27 wt% in the spin-solution was necessary to obtain any appreciable selectivities. The highest select ivity of n-pentane achieved by a hollow fiber (#14) was 28.7, whereas a selectivity of 65.2 was achieved by a flat sheet membrane (#PEI-8) i n previous work. Although selectivities of #PEI-8 were generally highe r than #14 including VOCs other than n-pentane, there was a notable ex ception in the case of toluene selectivity. Comparing the fluxes for a given selectivity, hollow fiber membranes were lower than flat sheet membranes.