不同天然矿物载体钼基催化剂悬浮床加氢裂化反应性能

Catalytic Performance of Molybdenum Based Catalysts Supported on Different Natural Minerals in Slurry-Phase Hydrocracking

选用累托土、铝土矿、高岭土3种天然矿物作为载体材料,采用浸渍法制备Mo基负载型悬浮床加氢裂化催化剂。系统考察不同天然矿物的组成结构和催化剂金属组分的还原性,揭示催化剂的组成性质与反应产物分布的关联性。通过XRF、XRD、N_(2)吸附-脱附和H_(2)-TPR等手段对天然矿物和催化剂进行表征分析,并以高温煤焦油为原料进行加氢裂化反应性能评价。结果表明:累托土和铝土矿中Fe_(2)O_(3)的质量分数分别为8.2%和19.1%,显著高于高岭土中Fe_(2)O_(3)的含量;由H2-TPR表征结果可知,累托土为载体的Mo基催化剂中含有较多的易被还原的Mo氧化物和Fe氧化物。累托土为载体的Mo基催化剂具有较好的悬浮床加氢裂化反应性能,石脑油和中间馏分收率为50.6%,明显高于铝土矿和高岭土为载体的Mo基催化剂,气体收率较低。

In this study,three natural minerals,including rectorite,bauxite and kaolin,were used as supports to prepare the Mo-based catalysts for slurry-phase hydrocracking by impregnation method.The compositions and structure of natural minerals,the reducibility of metal components on catalysts,and the relationship between catalyst properties and the product distribution were studied.Natural minerals and catalysts were characterized by X-ray fluorescence(XRF),X-ray diffraction(XRD),N_(2) adsorption-desorption and H_(2) temperature programmed reduction(H2-TPR).Results show that the mass fractions of Fe_(2)O_(3) in rectorite and bauxite are 8.2%and 19.1%,respectively,obviously higher than that of kaolin,and higher amounts of easily reduced Mo oxide and Fe oxide in the catalysts supported on rectorite are observed according to the H2-TPR result.The catalyst supported on rectorite presents better performance,in which the total yield of naphtha and middle distillates is 50.6%,significantly higher than that of the catalysts supported on bauxite and kaolin.Meanwhile,the corresponding yield of gas is lower than that of other catalysts.