Ni-Cu/γ-Al2O3催化剂的制备及其脱氢反应研究

The preparation of Ni-Cu/γ-Al2O3 catalyst and its research of dehydrogenation reaction

摘要:

采用共沉淀法、浸渍法和共沉淀—浸渍法制备了三种不同的Ni-Cu/γ-Al2O3双金属催化剂，利用微型连续管式反应器，考察了三种Ni-Cu/γ-Al2O3催化剂对氢能载体甲基环己烷（MCH）气相脱氢的催化性能。采用XRD、SEM、BET、BJH等手段对所制备的催化剂进行表征。结果表明：使用共沉淀—浸渍法制备的Ni-Cu/γ-Al2O3催化剂优于其他两种（三种催化剂中Ni和Cu负载量均为26%且Ni与Cu之比为8:1）。在反应温度673K，反应压力0.6Mpa，MCH/N2=19/27，混合进样体积空速240 h-1条件下，MCH脱氢转化率达到98.5%，产物甲苯的选择性接近100%。与铂等贵金属催化剂以及单金属镍催化剂相比较，镍铜双金属催化剂在本反应体系具有更好的应用前景。

Abstract:

The three different Ni-Cu/γ-Al2O3 bimetallic catalysts were prepared by co-precipitation method, impregnation method and co-precipitation - impregnation method. Under different conditions, the three Ni-Cu/ γ-Al2O3 catalysts for dehydrogenation of the hydrogen carrier catalytic performance were investigated by using a continuous tubular micro-reactor. XRD, SEM, BET and BJH were used to characterize the catalysts. The results showed that: Using Ni-Cu/γ-Al2O3 catalyst prepared by co-precipitation - impregnation method is better than the others (the Ni-Cu loading of the three catalysts were 26% and the proportion of nickel and copper was 8 to 1). Under the conditions of the reaction temperature 673K, reaction pressure 0.6Mpa, MCH/N2 = 19/27 and the volume of gas space velocity 240 h-1 , MCH dehydrogenation conversion rate reached 98.5% and the product selectivity was close to 100% .Besides, it is feasible that using the Ni-Cu/γ-Al2O3 bimetallic catalyst is better than the platinum or other noble metal catalysts and nickel catalysts in this reaction system.