Al_2O_3焙烧温度对乙炔选择加氢催化剂性能的影响

采用浸渍法制备了NiCu/Al2O3乙炔选择加氢催化剂,研究了焙烧温度对Al2O3结构、酸性及催化剂催化性能的影响,结果表明：随着焙烧温度的提高,Al2O3的晶相结构由γ相逐渐转变为δ相和θ相,最后转化为α相,比表面积降低而孔径增大;酸强度逐渐降低最后直至消失。随Al2O3载体焙烧温度的提高,NiCu/Al2O3催化剂上乙炔的转化率和乙烯的选择性同时增加,当焙烧温度为1100℃时,乙炔的转化率和乙烯选择性分别为89.3%和77.5%。

Effect of calcined temperature of Al2O3 on catalytic performance of acetylene selective hydrogenation catalyst

The Ni-based catalyst for selective hydrogenation of acetylene was prepared by impregnation method.The influences of calcination temperature on the structure and acid center of the Al2O3 and the performance of the as-prepared catalyst also were investigated.The results showed that with the increasing of the calcination temperature,the crystal phase of the Al2O3 was transferred from γ to δ and θ,ultimately existed only α phase,the specific surface area gradually decreases while the average pore size gradually increased.Meanwhile,The acid center keep reducing even disappered with increasing the calcination temperature.Both in acetylene conversion and ethylene selectivity show considerable improvements at evaluated temperature,acetylene conversion and ethylene selectivity at 1100℃ were 89% and 77%,respectively.