Polymer Brushes Supported Polyoxometalate Catalyst for Ultra-Deep Desulfurization of Diesel

Abstract

In this paper, a novel catalyst (PMo₁₂O₄₀-PDMAEMA-SiO₂) with polymer brushes as support was synthesized in this paper. The catalysts were characterized by thermogravimetric analysis and fourier transform infrared spectroscopy and the results suggested that PDMAEMA was formed on the surface of SiO₂ and [PMo₁₂O₄₀]^3– existed in the obtained catalyst. PMo₁₂O₄₀-PDMAEMA-SiO₂ was further used as oxidative catalyst in desulfurization process of dibenzothiophene dissolved in n-octane. PMo₁₂O₄₀-PDMAEMA-SiO₂ was found to be very effective for the oxidative removal of dibenzothiophene with desulfurization efficiency about 100 %. Experimental factors including type of different sulfur-containing compounds, O/S molar ratio, temperature, catalyst amount were evaluated and the optimal operating conditions were determined as O/S molar ratio, 24; reaction temperature, 60 ºC; the amount of catalyst, 0.008 g (5 mL model oil). Moreover, the new catalyst developed is reuseable. The recyclable PMo₁₂O₄₀-PDMAEMA-SiO₂ exhibited good catalytic performance and can be recycled for four times without significant decrease in catalytic activity. As a whole, PMo₁₂O₄₀-PDMAEMA-SiO₂ has high potential for using as an effective catalyst for deep desulfurization of diesel.