A series of B-Ni2P/SBA-15/cord monolithic catalysts were prepared by coating the slurry of the B-Ni2P/SBA-15 precursors on a pretreated cordierite support, and followed by temperature-programmed reduction in a H2 flow. The samples were characterized by X-ray diffraction （XRD） and N2 adsorption-desorption technique. The catalytic activities for the hydrodesulfurization （HDS） of dibenzothiophene （DBT） were evaluated. The results showed that Ni2P phase was present in all B-Ni2P/SBA-1 5/cord monolithic catalysts. The specific surface areas （SBET） of the B-Ni2P/SBA-15/cord monolithic catalysts was first increased to 167 m2· g-1, and then decreased to 155 m2· g-1 with the increase of boron contents. The catalytic activity also showed the similar trend with the increase of boron contents. The 1.75% （by mass） B-Ni2P/SBA-15/cord monolithic catalysts exhibited the highest DBT conversion of 98.4% at 380 ℃. The cordierite-based monolithic catalysts showed better low temperature sensitivity for HDS of DBT in comparison with the particle catalysts. Moreover, two HDS routes, direct desulfurization （DDS） and hydrogenation （HYD）, proceeded independently over B-Ni2P/SBA-15/cord monolithic catalysts and the main pathway was DDS.
A series of Co-Ni_2P/SBA-15 catalysts with various Co contents, Ni_2P contents and P/Ni molar ratios were prepared by impregnating nickel nitrate, diammonium hydrogen phosphate, and then cobalt nitrate into SBA-15 support followed by temperature-programmed reduction in a H_2 flow. The catalyst structure was characterized by X-ray diffraction （XRD）, high resolution-transmission electron microscopy （HR-TEM） and N_2 adsorption-desorption techniques and their catalytic performance of the hydrodesulfurization （HDS） of dibenzothiophene （DBT） was evaluated. The effects of Co contents, Ni_2P contents and P/Ni molar ratios on the catalyst structure and HDS of DBT over the Co-Ni_2P/SBA- 15 catalyst were investigated. The results indicated that the mesoporous structure was mainly maintained and the nickel phosphides were well dispersed in all of the characterized catalysts. The 4Co-25Ni_2P/SBA-15 （P/Ni = 0.8） catalyst with the Co and Ni_2P contents of 4 wt% and 25 wt%, respectively, and the P/Ni molar ratio of 0.8 showed the highest catalytic performance for HDS of DBT. Under the reaction conditions of 380 ℃ and 3.0 MPa, the DBT conversion can reach 99.62%. The HDS of DBT proceeded mainly via the direct desulfurization （DDS） pathway with biphenyl （BP） as the dominant product on all of the catalysts and the BP selectivity was slightly enhanced after the introduction of Co promoters.
Zhou-jun WangPingyi WuLing LanKunhong LiuYaqiong HuShengfu Ji
