液相法Ru-M-B/ZrO_2催化苯选择加氢制环己烯

Liquid Phase Selective Hydrogenation of Benzene to Cyclohexene over Ru-M-B/ZrO_2 Catalysts

评价了用化学还原法制备的 Ru-M-B/Zr O2 的性质 .研究了传质和反应改性剂 Zn SO4 · 7H2 O对Ru-M-B/Zr O2 活性和选择性的影响 .在反应体系中加入水可以提高环己烯的选择性 ,合适的水苯比为水 :苯 =2∶ 1 (V/V) .搅拌速率应控制在 90 0 r/min以上 ,以消除外扩散的影响 ;采用纳米级 Zr O2作活性组分分散剂 ,可消除内扩散的影响 .作为反应改性剂 Zn SO4 · 7H2 O的最佳浓度为 0 .5 mol/L.

The activity and selectivity of Ru-M-B/ZrO 2 catalysts prepared from chemical reduction method are evaluated. A detailed study of the influence of mass transfer and reaction modifier on the performance of catalysts is carried out. It is found out that the introduction of water to the reaction system could increase the selectivity to cyclohexene and the suitable volume ratio of water to benzene should be 2∶1. The stirring rate should be controlled above 900 r/min to eliminate the limit of external diffusion. Furthermore, superfine ZrO 2 is used as dispersion for Ru active agent to eliminate the limit of internal diffusion.The optimum concentration of reaction modifier ZnSO 4·7H 2O is 0.5 mol/L.