用于苯选择加氢制环己烯的非晶态合金Ru-La-B/ZrO_2催化剂的失活与再生

Deactivation and Regeneration of Amorphous Ru-La-B/ZrO_2 Catalystfor Selective Hydrogenation of Benzene to Cyclohexene

研究了在中试装置上经长期运转后的非晶态合金Ru La B/ZrO2 催化剂的失活原因与再生方法.结果表明:催化剂失活不是由微孔堵塞、比表面积减小、晶粒长大或催化剂中毒而引起的,而是由于在长期运转过程中催化剂吸附了反应浆液中的Zn2 +和反应器壁引入的Fe2 +,通过酸洗的方法可以使催化剂的活性和选择性基本恢复.

The amorphous Ru-La-B/ZrO2 catalyst was prepared and used for the selective hydrogenation of benzene to cyclohexene in the pilot plant. Ru-La-B/ZrO2 showed satisfied activity, selectivity, stability, subside and separate performance. The deactivation reasons for the catalyst running for a long time in the pilot plant were investigated by measuring surface area, pore diameter distribution and ion content in the catalyst as well as in slurry. It was found that the catalyst deactivation was not caused by the plugging of catalyst micropores, decrease in surface area, crystalline grain growth or catalyst poisoning. It was just because that excess Zn2+ and Fe2+ from the reaction slurry were adsorbed on the catalyst. After washing with acid, the activity and selectivity of the catalyst were almost completely recovered. This acid-washing method prolongs the catalyst life and make the catalyst open up a very good prospect in industrialization.