炭改性对Ni/Al_2O_3催化剂顺酐加氢合成γ-丁内酯反应性能的影响

Effect of Carbon Modification on Ni/Al_2O_3 Catalyst for Hydrogenation of Maleic Anhydride to Butyrolactone

通过热解蔗糖/Al2O3前驱体的方法制备了炭包覆改性Al2O3(CCA)载体,并采用等体积浸渍制备了负载量17%的镍基催化剂.对载体及相应催化剂进行了TPO-MS、N2物理吸附、TPR、XRD等测试表征,并考察了催化剂顺酐(MA)加氢合成γ-丁内酯(GBL)的反应性能.结果表明,适量炭的引入改变了载体Al2O3的表面性质,使金属-载体相互作用减弱,活性组分镍的分散度提高,催化剂在MA加氢反应中表现出高的GBL选择性.当Al2O3中引入8.9%的炭时,催化剂表现出最高的催化活性,在210℃,5 MPa氢气压力下反应3 h时,MA转化率达98%以上,GBL选择性达91.71%.

Carbon-covered alumina（CCA） was prepared by the pyrolysis of the sucrose dispersed on a γ-Al2O3 support.17% loading Ni supported catalysts were prepared by impregnation method.Effect of carbon addition on Ni/Al2O3 catalytic performance was investigated for the hydrogenation of maleic anhydride（MA） to butyrolactone（GBL）.The samples were characterized by TPO-MS,N2 adsorption,TPR and XRD.The results indicated that the addition of carbon resulted in the change of the surface property of Al2O3 support,the Ni dispersion and metal-support interaction of the catalysts.The catalysts showed different hydrogenation activity.When the carbon loading was about 8.9%,the catalyst showed the highest Ni dispersion and the mild metal-support interaction.The catalyst exhibited the highest selectivity of GBL for the hydrogenation of MA.At conditions of 210 ℃,5 MPa hydrogen pressure and reaction time 3 h,the conversion of MA was above 98% and the selectivity of GBL was 91.71 %.