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钼和镧是好的镍硼触媒的促进剂, 对于对氯硝基苯氢化反应有好的效果, 因此同时加入钼和镧在镍硼触媒上应该是有趣的研究题目. 本研究利用化学还原法制备了一系列含有不同量镧的镧钼镍触媒, 醋酸镍、钼酸胺及硝酸镧同时加入含有甲醇的水溶液中. 以X光绕射, 穿透式电子显微镜、高分辨率电子显微镜及X光光电能谱仪鉴定了这些触媒. 对氯硝基苯氢化反应是在批次反应器中于333 K、1.2 MPa氢气压力及500 r/min转速下操作. 即使在镍钼硼中加入很少量的镧, 对提高活性及对氯苯胺的选择性都有显著的效果, 加入适量的镧可以抑制镍钼硼的长范围的结晶排列, 并保持镍钼硼在非结晶状态. 镧以氧化态存在, 其功效为阻隔物, 避免镍钼硼聚集, 但是过量的镧会有相反的效果, 镧和镍的适当比例是0.2.
Molybdenum and lanthanum are good promoters of nickel-boron catalyst, and have a good effect on the hydrogenation of p-chloronitrobenzene, so adding molybdenum and lanthanum together should be an interesting research topic on the nickel-boron catalyst.In this study, chemical reduction A series of lanthanum molybdenum-nickel catalysts with different amounts of lanthanum were prepared, and nickel acetate, molybdate and lanthanum nitrate were simultaneously added into aqueous solution containing methanol.The effects of X-ray diffraction, transmission electron microscope, high resolution electron microscope and X These catalysts were identified by photoemission spectroscopy. The p-chloronitrobenzene hydrogenation reaction was operated in a batch reactor at 333 K, 1.2 MPa hydrogen pressure and 500 r / min. Even with little addition of nickel-molybdenum-boron The amount of lanthanum has a significant effect on both the activity and the parachloroaniline selectivity. The addition of the appropriate amount of lanthanum suppresses the long-range crystal ordering of the nickel-molybdenum-boron and keeps the nickel-molybdenum-boron in the amorphous state. Exists, its effectiveness as a barrier to avoid the accumulation of nickel molybdenum boron, but an excess of lanthanum will have the opposite effect, the appropriate ratio of lanthanum and nickel is 0.2.