NiO/Al_2O_3基催化剂的TPR特性研究

NiO/Al_2O_3基催化剂用于替代贵金属催化剂,被广泛应用于石油和石化领域生产过程的加氢、脱硫和脱氮。采用TPR方法,研究不同Ni含量NiO/Al_2O_3及不同载体的催化剂还原特性。结果表明,NiO/Al_2O_3催化剂在10%H_2-Ar气氛下,还原温度范围较宽,为(300~800)℃,其中,(500~600)℃还原速率最大;随着NiO含量的增加,起始还原温度降低,还原耗氢量按比例增加;以MgO为载体的NiO催化剂还原呈现双峰特征,以SiO2和TiO2为载体的NiO催化剂的初始还原温度比NiO/Al_2O_3催化剂降低(100~200)℃。

Study of reduction properties of NiO/Al2O3 catalysts by temperature-programmed reduction

Instead of noble metal catalysts,NiO/Al₂O₃ catalysts were widely applied to production processes of petroleum and petrochemical fields for hydrogenation,desulfuration and denitrification.In this paper,the reduction performance of NiO/Al₂O₃ catalysts with different nickel loadings and different supports was studied by temperature-programmed reduction.The results indicated that under the condition of 10%H₂-Ar atmosphere,the reduction temperature of NiO/Al₂O₃ catalyst was (300-800) ℃.The fastest reduction rate of NiO/Al₂O₃ catalyst was obtained when the reduction temperature was (500-600) ℃. With the increase of NiO contents,the starting reduction temperature was lowered,and the amount of hydrogen consumption was increased.Using MgO as the support,the reduction curve of NiO/MgO catalyst exhibited double peaks.Compared with NiO/Al₂O₃ catalyst,the starting reduction temperatures of the catalysts with SiO₂ and TiO₂ as the supports were lowered (100-200) ℃.