Adsorptive Denitrogenation and Desulfurization of Diesel Fractions by Mesoporous SBA15-Supported Nickel(II) Phosphide Synthesized through a Novel Approach of Urea Matrix Combustion

Stringent environmental regulations on the sulfur content in transportation fuels have made ultradeep desulfurization of diesel an important research topic One of the approaches to promote the effectiveness of the conventional hydrodesulfurization (HDS) process is to remove the organic nitrogen containing compounds from the feed before HDS. Adsorptive removal of nitrogen compounds at room temperature and pressure without the presence of hydrogen was studied using a high capacity adsorbent, Ni2P/SBA15, which was prepared by the urea matrix combustion (UMxC) method. A metal loading of 7 wt % Ni was observed to be optimum among the loadings tested. The nitrogen adsorption capacity reached 9.1 mg/g of adsorbent, which is higher than the capacities of most of the reported adsorbents. Ni2P/SBA15 was characterized by Brunauer-Emmett-Teller analysis, X-ray diffraction, Fourier transform IR spectroscopy, and transmission electron microscopy (TEM). The mesoporous nature of the adsorbent was confirmed by nitrogen adsorption/desorption analysis as well as TEM analysis. Uniform dispersion of Ni2P was observed in TEM images. Solvent washing regeneration was studied, and four adsorption-and-regeneration cycles were carried out. Approximately 95% of the adsorptive capacity of the sorbent was recovered after four cycles.