Efficient desulfurization by polymer–inorganic nanocomposite membranes fabricated in reverse microemulsion

Abstract

The sulfur in gasoline will convert to SO2 after combustion under high temperature, which adversely affects human health and the environment. Membrane technique in particular pervaporation offers a number of potential advantages over conventional FCC gasoline desulfurization processes. The present study focuses on the performance enhancement of PDMS membrane by incorporating silica nanoparticles. Specifically, silica nanoparticles formed by the catalysis and templating of protamine in w/o reverse microemulsion are in situ embedded into PDMS bulk matrix, endowing the resultant oleophilic nanocomposite membranes with appropriate free volume properties and superior separation performance. Through the rational manipulation of biomimetic mineralization at water–oil interface, silica particles with uniform size are acquired. Following this protocol, by introducing organic PDMS oligomers into the oil phase, PDMS–SiO2 nanocomposite membranes are prepared in a facile way. The resultant nanocomposite membranes display superior permeability and permselectivity in the pervaporative desulfurization using thiophene/n-octane binary mixture as model gasoline, for example, under the condition of 500ppm sulfur in feed (40L/h) at 30°C, an enrichment factor of 4.83–5.82 with a normalized permeation rate of 6.61–10.76×10−5kgm/m2h is acquired.