This Small Business Innovation Research (SBIR) Phase I project addresses the development of a unique, scalable membrane pervaporation process that can be used in a wide array of separations that are of national and economic importance. This research will demonstrate the technical viability of a novel pervaporation system, which generates its vacuum by passing a special working fluid through a Venturi nozzle. More specifically it will show that an intermediate cat naphtha stream having up to 2000 ppm sulfur can be selectively separated into (1) an aromatic-rich permeate fraction that contains almost all of the sulfur-bearing molecules and (2) a virtually sulfur-free saturate-rich retentate fraction that contains almost all of the olefins. A small scale laboratory system will be used to generate permeation rate and quality data on model feeds using membranes that have previously been shown to have high aromatic/aliphatic selectivities. One application of particular interest is the reduction of sulfur in gasoline. The National Petroleum Council has estimated that it will cost U.S. refiners $8 billion in 1998 dollars to meet the 30 ppm Tier 2 requirement for sulfur in gasoline, primarily because of the limitations of existing commercial hydrotreaters. If successfully demonstrated, this technology could be used in tandem with existing hydrotreaters worldwide to allow refiners to more cost effectively meet lowered sulfur specifications for gasoline.