超声/微波一体化制备SiO_(2)负载Ni催化剂及其高效催化烯烃加氢反应研究

Highly efficient SiO_(2) supported Ni catalyst prepared by ultrasonic-microwave method for catalytic hydrogenation of olefins

以Ni(NO_(3))_(2)·6H_(2)O和SiO_(2)(Degussa)为原材料,利用超声/微波一体化方法合成催化剂10%Ni/SiO_(2),并对催化剂合成条件如合成方式、温度、时间、超声功率、微波功率等进行了探讨.之后对催化剂进行XRD、BET、SEM、TEM、XPS和H_(2)-TPR等表征,发现超声微波一体化合成的催化剂具有更大的比表面积、更小的金属粒径、粒子分布均匀以及形状较为规整.将催化剂用于催化环烯烃加氢反应时,烯烃转化率与相应环烷烃产物的选择性都较高,在90℃、1 h、超声功率为500 W、微波功率为150 W的合成条件下催化加氢活性最好,环己烯的转化率高达97.0%,产物环己烷选择性为100%.

Using Ni(NO_(3))_(2)·6H_(2)O and SiO_(2)(Degussa)as the raw materials,10%Ni/SiO_(2)catalyst was synthesized by ultrasonic-microwave synergistic method.The catalyst synthesis conditions such as synthesis methods,synthesis temperature,time,ultrasonic power,microwave power were further discussed.All the catalysts were characterized by XRD,BET,SEM,TEM,H_(2)-TPR and XPS.It was found that the catalyst synthesized by ultrasonic-microwave synergistic method had larger specific surface area,smaller metal nanometer particle size,uniform distribution and more regular shape.When the catalyst was used for the catalytic hydrogenation of cyclic olefins,the conversion of olefins and the selectivity of cyclic alkanes were high.It was found that 10%Ni/SiO_(2)catalyst had the best catalytic activity under the synthesis conditions of 90℃,1 h,500 W of ultrasonic power and 150 W of microwave power,the conversion of cyclohexene could reach 97.0%,and the selectivity of cyclohexane was 100%.