Desulfurization of Gasoline by Pervaporation

Worldwide concerns over the environment have stimulated increasing interest both in academic and industry for the deep desulfurization of gasoline. Due to some inherent disadvantages associated with the conventional hydrodesulfurization, several non-conventional techniques are being tried by researchers. Pervaporation is such a recently developed technology for gasoline desulfurization. Its efficiency has attracted worldwide attention. Compared with conventional sulfur removal technology for gasoline, pervaporation exhibits advantages of little reduction of octane number, low energy consumption, environmental benefits, simple operation, and easy scale-up. The advances of pervaporative operation for gasoline desulfurization are reviewed in this paper. The membrane materials used for desulfurization include polysiloxane, poly(ethylene glycol), polyimide, polyurethane and organic-inorganic hybrid membranes. Analysis of the selectivity-permeability with varying feed composition and operating parameters are investigated. Because of the attractive economic figures and high efficacy, the refiners expect that pervaporative desulfurization of gasoline shall soon become very important, either alone or coupled with presently available technologies.