The C-Si Janus nanoparticles with supported phosphotungstic active component for Pickering emulsion desulfurization of fuel oil without stirring

Abstract

Phosphotungstic active component (PW12O403−) was supported on the bi-component carbon-organosilica Janus particles to prepare an amphiphilic catalyst for oxidative desulfurization, and it was analyzed by a series of characterization. Its catalytic performance in different systems including n-octane/acetonitrile, n-octane/BimPF6, n-octane/BimBF4, n-octane/methanol, and n-octane/water, was evaluated. According to the results, the stable Pickering emulsion was formed in n-octane/acetonitrile system which exhibited the best desulfurization performance, corresponding to the final desulfurization ratio of 99.86%. Compared with the conventional bi-phase system using H3PW12O40 as catalyst, the desulfurization ratio was sharply increased. Besides, the prepared amphiphilic catalyst could be easily recovered by centrifugation, which was unattainable for the conventional amphiphilic heteropoly acid catalyst. The desulfurization ratio could achieve above 98% even after the catalyst was reused for 5 times. Due to its excellent catalytic performance for the model oil with different initial sulfur content and different sulfur-containing compounds, good recyclability, and outstanding selectivity, the prepared catalyst was evaluated for real oil desulfurization, and a satisfactory result was achieved. The excellent desulfurization performance was attributed to the micrometer-scale droplets formed in Pickering emulsion to result in good mixing.