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将化学还原法制备的Ni-Zr-B非晶态合金催化剂用于硝基苯液相加氢制苯胺的反应,并通过XRD,TEM和H2-TPD技术对催化剂进行表征,研究了Zr含量对Ni-Zr-B催化剂微观结构和其催化加氢性能的影响。结果表明,Ni-B非晶态合金催化剂表现出较高硝基苯转化率和苯胺选择性,Zr助剂的引入减小了催化剂非晶态结构短程有序范围和催化剂粒径,粒径由60nm减小至10nm左右;增多了Ni活性中心数,并减弱了Ni化学吸附氢强度,使得吸附的氢物种更易于在各吸附中心间迁移并参与反应,导致Ni-B非晶态合金催化硝基苯加氢的活性和选择性进一步提高。当Zr含量为8%时,催化剂具有最优的催化加氢性能,硝基苯转化率和苯胺选择性分别高达99.6%和100%。
The Ni-Zr-B amorphous alloy catalysts prepared by chemical reduction method were used for the reaction of nitrobenzene in the liquid-phase hydrogenation to aniline. The catalysts were characterized by XRD, TEM and H2-TPD. Effect of Ni-Zr-B Catalyst Microstructure and Catalytic Hydrogenation Performance. The results show that the Ni-B amorphous alloy catalysts exhibit higher nitrobenzene conversion and aniline selectivity. The introduction of Zr promoter reduces the short-range order of the amorphous structure of the catalyst and the catalyst particle size. 60nm reduced to about 10nm; increase the number of Ni active center, and weakened the strength of Ni chemisorbed hydrogen, making the adsorption of hydrogen species more likely to migrate between the various adsorption centers and participate in the reaction, resulting in Ni-B amorphous alloy catalyst nitrate The hydrogenation activity of the benzene and the selectivity are further improved. When the content of Zr is 8%, the catalyst has the best performance of catalytic hydrogenation, the nitrobenzene conversion and aniline selectivity are as high as 99.6% and 100% respectively.