Highly Oxidative Desulfurization of Thiophenic Model Fuels and Real Gasoline by Keggin-type Heteropolyanion Immobilized on Polyaniline and Chitosan As an Efficient Organic-Inorganic Nanohybrid Catalyst

To obtain clean gasoline, a new nanohybrid catalyst (TPA@PAN@CH) was synthesized by immobilizing tungstophosphoric acid (TPA) on the surface of polyaniline (PAN) and chitosan (CH) polymers. The features of the materials were detected by FT-IR, UV/vis, XRD, FE-SEM, and EDX methods. The XRD patterns demonstrate that the average crystallite size of the TPA@PAN@CH is estimated to be approximately 45 nm, which corresponds to the results of the FE-SEM. The catalytic performance of the TPA@PAN@CH was tested in the nano-catalytic oxidative desulfurization (Ncat-ODS) of gasoline and model fuels by H2O2/AcOH (volume proportion of 2:1) oxidizing agent. The best desulfurization outcomes were achieved by 0.1 g of the TPA@PAN@CH as a nanocatalyst at 35 degrees C under mild reaction conditions. Based upon the above findings, the sulfur content could be declined from 0.4986 to 0.0193 wt%, which corresponds to performance of 96%. Mercaptan concentration decreased from 98 to 4 ppm, and the removal efficiency of model fuels declined in the order of DBT >= BT > Th. The high catalytic activity of TPA@PAN@CH was maintained for five cycles without significantly diminishing its performance. This work suggested the potential application of the TPA@PAN@CH for eliminating of hazardous sulfur compounds that significantly affect the efficacy of the Ncat-ODS.