Mono Mn(II)-substituted phosphotungstate@modified graphene oxide as a high-performance nanocatalyst for oxidative demercaptanization of gasoline

In this study, the removal of hazardous sulfur compounds from gasoline was provided based on catalytic oxidation demercaptanization technique. The cesium salt of mono Mn(II)-substituted Keggin-type polyoxometalate Cs5PMnW11O39 (PMnW11) was successfully synthesized and immobilized on modified graphene oxide (mGO) as a new nanocatalyst (PMnW11@mGO) for demercaptanization process. The synthesized materials were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet-visible (UV-vis), Fourier transform infrared spectroscopy (FT-IR), and cyclic voltammetry (CV) analysis. Characterization of the prepared nanocomposite was confirmed that the structures of the PMnW11 and mGO were retained after immobilization. The sulfur-containing molecules in real gasoline and simulated fuel were oxidized and extracted efficiently under mild reaction condition. After treatment, the mercaptans and total sulfur content of real gasoline were lowered with 98.8% and 98% yield, respectively. The PMnW11@mGO hybrid nanocatalyst was separated and reused conveniently at the end of the reaction for five times. The excellent performance of this new catalytic oxidation system can be a promising rout to achieve ultra-clean gasoline. (C) 2017 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.