【摘要】 制备了一系列铜质量分数不同的CuN i/γ-A l2O3催化剂,进行了TPR和XRD表征并测定了该系列催化剂对苯加氢制环己烷的催化活性。结果表明,助剂Cu的负载量对低温(160℃)还原后催化剂的催化活性影响很大,在铜镍原子摩尔比为1∶1时,催化剂具有较高的催化活性和稳定性;添加铜组分可促进镍在载体表面分散,使负载N iO的还原温度降低,催化活性提高。更多还原

【Abstract】 A series of CuNi/γ-Al₂O₃ catalysts with different Cu contents were prepared and evaluated by the gas-phase benzene hydrogenation as a probe reaction.After reduction at 160℃,the Cu-promoted CuNi/γ-Al₂O₃ catalysts exhibited considerably higher activity than Ni/γ-Al₂O₃ catalysts,and the copper content played an important role in the catalyst reducibility and catalytic activity.The catalyst,CuNi/γ-Al₂O₃ with copper to nickel atomic ratio 1∶1,exhibited best catalytic activity and stability.XRD（X-ray diffraction） results showed that the addition of copper to the Ni/γ-Al₂O₃ catalysts significantly improved the dispersion of NiO over γ-Al₂O₃,the CuNi/γ-Al₂O₃ with copper to nickel atomic ratio 1∶1 had optimal dispersion,and further addition was accommodated by the decreasing of the dispersion of NiO.TPR（temperature programmed reduction） results suggested the addition of copper promoted the reducibility of supported nickel oxide by enhancing surface segregation of a NiO-like phase,while copper to nickel atomic ratio in excess of 3∶5 had practically no additional promoting effect.更多还原