Pervaporation Desulfurization of a Thiophene/n-Octane Mixture Using PPO Membranes Modified with Hybrid Star-Shaped Macromolecules

The presence of sulfur-containing impurities in petroleum naphtha causes a decrease in the cost and quality of fuels, a reduction in the service life of car engines, and an increase in the amount of harmful emissions into the atmosphere. Pervaporation is an alternative cost-effective fuel desulfurization method. In this study, hybrid membranes based on poly(2,6-dimethyl-1,4-phenylene oxide) and a star-shaped modifier for the pervaporation separation of a thiophene/n-octane model mixture is developed. Hybrid star-shaped macromolecules comprising six polystyrene arms and six poly(2-vinylpyridine)-block-poly(tert-butyl methacrylate) diblock copolymer arms grafted onto a common fullerene C60 central core are used as the modifier. Membrane structure is analyzed by scanning electron microscopy and atomic force microscopy. Thermal properties are studied by differential scanning calorimetry. The separation properties of the membranes are determined at low thiophene concentrations (up to 0.08 wt %). It is shown that the introduction of a star-shaped modifier leads to an increase in the extraction efficiency of sulfur-containing impurities from octane, which is the main fuel component.