Ni/Al2O3-SiO2催化剂对C4单烯烃加氢的催化性能

利用XRD、H2 TPR和孔结构的分析对C4馏分加氢催化剂Ni/Al2O3 SiO2进行了表征，在固定床反应器内对催化剂的活性进行了评价，并对加氢机理进行了讨论。结果表明，在Ni/Al2O3 SiO2催化剂表面至少存在两种活性中心，分别由体相NiO和高度分散的NiO还原产生。研制的催化剂对C4馏分加氢具有很高的活性和良好的稳定性，进口温度18.6℃时就可进行加氢，属于低温型加氢催化剂。在 C4单烯烃质量分数为74.85%、加氢压力为2.0MPa~2.7MPa、液时空速为1.0h－1~2.0h－1、氢油体积比为 300~450下，原料中单烯烃转化率在98%以上。催化剂连续运行342h，其活性基本保持不变。

Catalytic activity of Ni/Al2O3-SiO2 catalyst for hydrogenation of mono-olefins in C4 fraction

Ni /Al2O3 SiO2 catalyst for hydrogenation of C4 fraction was characterized by XRD, H2 TPR and pore structure analysis. The hydrogenation conditions and catalytic stability were examined in a fixed bed reactor and the hydrogenation mechanism of catalyst was also discussed. The H2 TPR results indicated that at least two kinds of active centers were produced on the surface of catalyst by reduction of crystallite NiO and commendable disperse NiO, respectively. Compared with other catalysts, the inlet temperature of this catalyst 18.6℃ was far lower than the reported temperature 180℃~200℃. So the Ni /Al2O3 SiO2 catalyst is a kind of low temperature hydrogenation catalyst. The conversions of mono olefines in C4 fraction was over 98% at 2.0MPa~2.7MPa when the mass fraction of mono olefines in C4 fraction was 74.85%, the reaction temperature was 15℃~25℃，the volume space time velocity was 1.0h－1~2.0h－1 , and the volume ratio of H2 to light C4 was 300~450. With the application of Ni/Al2O3 SiO2 catalyst, 342h stability test shows that the catalyst has relatively high activity and excellent stability with promising prospects for industrial application.