Effect of reduction temperature on the performance of Ni2P/Ti-MCM-41 catalyst in hydrodesulfurization

The supported Ni2P/Ti-MCM-41 catalyst is prepared by temperature-programmed reduction method with nickel chloride (NiCl2·6H2O) as the nickel precursor, ammonium hypophosphite (NH4H2PO2) as the phosphorus precursor and Ti-MCM-41 as the support. The Ni2P/Ti-MCM-41 catalyst was characterized by H2-TPR, XRD, BET, XPS, and TEM; the effect of reduction temperature on its catalytic performance in hydrodesulfurization (HDS) was investigated by using dibenzothiophene (DBT) as a model compound. The results show that the precursors on the catalyst prepared in this way can be reduced at 318℃, which is at least 200℃ lower than that prepared by traditional methods. Pure Ni2P phase can be obtained by reduction at 350-500℃; the low reduction temperature is in favor of forming small Ni2P crystallite size. The Ni2P/Ti-MCM-41 catalyst obtained at a reduction temperature of 400℃ exhibits the highest surface area, the best dispersion of Ni2P crystallite size, the lowest surface phosphorus content and the highest HDS activity; under 340℃, 3.0 MPa, a H2/oil ratio of 500 (volume ratio) and a weight hourly space velocity (WHSV) of 2.0 h-1, the conversion of DBT for HDS reaches 99.4%. © 2016, Science Press. All right reserved.