Ni基催化剂在邻甲酚原位加氢反应中的催化性能

采用等体积浸渍法制备了一系列负载型Ni基催化剂，利用XRD、H2-TPR、NH3-TPD 等技术表征了催化剂的理化特性，考察了载体（CMK-3、SiO2ZrO2、MgO、Al2O3）、助剂（Cu、Ce、Fe）对Ni基催化剂理化特性的影响，测试了230 oC、0.1 MPa冷压下催化剂对邻甲酚原位加氢反应的性能．结果表明，在负载型镍基催化剂作用下，甲醇水相重整制氢反应可以与邻甲酚的原位加氢反应相耦合；以CMK-3为载体的催化剂活性明显优于其他三种载体，邻甲酚的转化率为45.35%；助剂的添加对催化剂性能影响显著，Fe 的引入使原位加氢体系的转化率降至40.49%，助剂Ce、Cu的加入提高了Ni/CMK-3催化剂的原位加氢反应性能，转化率分别提高至64.6%、66.8%，Cu的添加改变了产物的分布，在产物中出现了新产物甲苯；同时探讨原位加氢反应路径及反应机理．

Effects of Supports and Promoters on in situ Hydrogenation of o-Cresol over Ni-based Catalysts

We investigated the effects of supports （CMK-3, SiO2ZrO2, MgO, Al2O3） and promoters （Cu, Ce, Fe） on textual properties of Ni based catalysts. o-Cresol was used as a probe to test the activity of these catalysts under the condition of 230 ℃ and nitrogen pres-sure of 0.1 MPa. The catalysts were characterized by X-ray diffraction, H2 temperature programmed reduction ammonium programmed desorption, and N2 adsorption-desorption isotherms. The results showed that the catalytic performance of Ni/CMK-3 （the conversion of o-cresol reached 45.4%） was significantly better than the other three kinds of supports. The modification of Ni/CMK-3 was also investigated and over 60% conversion of o-cresol was obtained after the addition of Ce （64.6%）and Cu （66.8%） in Ni/CMK-3, whereas the addition of Fe led to a decrease of conversion. In the meantime, Cu changed the products dis-tribution. The appearance of toluene indicated that another pathway existed in the reaction.Accompanied by the ascension of conversion in both sides, side effects also occurred and got more serious. The apparent order of activity for all the tested catalysts was NiCe/CMK-3〉NiCu/CMK-3〉Ni/CMK-3〉NiFe/CMK-3〉Ni/Al2O3Ni/SiO2ZrO2〉Ni/MgO. The reac-tion pathway, involving three routes, was also mentioned in this study.