Co助剂对Ni-B非晶态催化剂微观结构和加氢性能的影响  

Influence of Co on Microstructure and Catalytic Performance of Ni-B Catalyst for Dinitrotoluene Hydrogenation

作　　者：闫少伟[1,2] 范辉 梁川[1] 于智慧[1] 李忠[1] 

机构地区：[1]太原理工大学煤科学与技术国家重点实验室培育基地,太原030024 [2]赛鼎工程有限公司,太原030024

出　　处：《太原理工大学学报》2012年第4期415-420,共6页Journal of Taiyuan University of Technology

基　　金：山西省归国留学人员基金资助项目(20100038)

摘　　要：通过化学还原法制备了一系列Ni-B非晶态合金催化剂,研究了n(KBH4)/n(Ni)和Co含量对Ni-B非晶态合金催化剂微观结构及其催化二硝基甲苯(DNT)合成甲苯二胺(TDA)性能的影响。通过XRD和H2-TPD技术对催化剂微观结构表征表明,随着n(KBH4)/n(Ni)的增大,NiB2含量增多,催化剂的加氢性能先增大后减小;当n(KBH4)/n(Ni)=4时,Ni-B非晶态合金的催化加氢性能最优。Co助剂的引入增大了Ni-B非晶态合金的无序程度,降低了Ni活性中心对H2的吸附强度,使得H2物种更容易在催化剂表面流动并参加反应,进一步增大了Ni-B催化DNT加氢合成TDA的活性和选择性。当Co的摩尔分数为6%时,Ni-Co-B非晶态合金催化剂的性能最优,DNT转化率为96.8%,TDA的选择性达100%。A series of amorphous Ni-La-B catalyst was prepared by KBH4 reduction for liquid phase hydrogenation of dinitrotoluene（DNT） to diaminotoluene（TDA）. The effect of n（KBH4 ）/ n（Ni） and Co content on microstructure and catalytic performance of Ni-B amorphous alloy catalyst was investigated. The characterizations of XRD and H2-TPD show that the content of NiB2 increased and the hydrogenation performance of Ni-B first increased and then decreased with increasing n （KBH4）/n （Ni）. When n （KBH4）/n （Ni） = 4, the performance of Ni-B was the best. The addition of Co enhanced the extent of long-range disorder, weakened the strength of Ni-H bond and further enhanced the performance of Ni-B. When Co addition was 0. 6%（molar concentration）, Ni-Co-B catalyst exhibited the best catalytic performance for dinitrotoluene hydrogenation, the conversion of the DNT and the selectivity of TDA were 96.8% and 100, respectively.

关 键 词：NI-B非晶态合金 二硝基甲苯 甲苯二胺 n(KBH4)/n(Ni) Co助剂 

分 类 号：O643[理学—物理化学]