Ni_2P/SiO_2/堇青石整体式催化剂的制备及加氢脱硫性能  

Preparation and Hydrodesulfurization Catalytic Performance of Ni_2P/SiO_2/Cordierite Monolithic Catalysts

作　　者：董亮[1] 季生福[1] 吴平易[1] 魏妮[1] 郭亚男[1] 刘辉[1] 朱吉钦[1] 李成岳[1] 

机构地区：[1]北京化工大学,化工资源有效利用国家重点实验室,北京100029

出　　处：《无机化学学报》2009年第9期1651-1656,共6页Chinese Journal of Inorganic Chemistry

基　　金：国家重点基础研究规划项目(973)(No.2006CB202503);国家自然科学基金项目(No.20473009)资助

摘　　要：以硝酸镍为镍源、磷酸为磷源,与硅溶胶按一定比例混合,制成混合物浆料,然后采用浸渍法将混合物浆料负载于处理好的堇青石蜂窝陶瓷载体上,经过干燥、焙烧后制得含磷化镍前驱体的整体式催化剂,再经氢气气氛下程序升温还原,制得一系列不同镍含量的磷化镍/SiO2/堇青石整体式催化剂。采用XRD、N2吸脱附和SEM等现代分析测试手段对催化剂的结构进行了表征。以二苯并噻吩为模型含硫化合物,对催化剂的加氢脱硫活性进行了评价。结果表明,磷化镍/SiO2/堇青石整体式催化剂中,Ni含量小于3.2wt%时,磷化镍在堇青石表面高度分散,Ni含量大于6.4wt%时,催化剂的活性相是Ni2P,催化剂的平均孔径在3.6nm左右,催化活性层平均厚度约为20μm。在液时空速(LHSV)为1.9h-1时,Ni含量为12.8wt%的催化剂具有最高的加氢脱硫活性,在360℃时二苯并噻吩的转化率为92.0%,联苯的选择性为69.8%,环己基苯的选择性为30.2%,反应主要按直接脱硫机理进行。The monolithic catalysts containing nickel phosphide precursors were prepared by dipping the silica sol containing nickel nitrate and phosphoric acid into the pretreated cordierite （Cord） support. Then, a series of Ni2P/SiO2/Cord monolithic catalysts with different Ni contents were prepared by temperature-programmed reduction method in H2 flow. The structure of the catalysts was characterized using X-ray diffraction （XRD）, N2 adsorption-desorption and scanning electron microscope （SEM）. The catalytic performances of the hydrodesulfurization （HDS） were evaluated in a fixed-bed micro-reactor using dibenzothiophene （DBT） as the model compound. The XRD results indicated that the nickel phosphides were well dispersed on the surface of catalysts while the Ni content was less than 3.2wt%. However, there was the Ni2P phase in the Ni2P/SiO2/Cord catalysts while the Ni content was more than 6.4wt%. The results of N2 adsorption-desorption isotherms showed that the pore size of the catalysts was around 3.6 nm. The SEM results show that the coating thickness of the cordierite support was about 20 μm. The active evaluation results indicated that the Ni2P/SiO2/Cord monolithic catalysts had very good catalytic performances for the HDS. The conversion of the DBT can reach 92.0% under the condition of the liquid hourly space velocity （LHSV） of 1.9 h^-1 and reaction temperature at 360 ℃ in the Ni2P/SiO2/Cord monolithic catalysts with Ni content of 12.8wt%. Simultaneity, the selectivity of biphenyl （BP） and cyclohexylbenzene （CHB） were 69.8% and 30.2%, respectively. It was indicated that the mechanism of the HDS was mainly the direct desulfurization （DDS） over the Ni2P/SiOJCord catalysts.

关 键 词：磷化镍 堇青石 整体式催化剂 加氢脱硫 二苯并噻吩 

分 类 号：O643[理学—物理化学]