超声浸渍法制备负载型镍基催化剂及其催化性能

Preparation of supported nickel-basd catalyst by ultrasonic impregnation method and its catalytic performance

分别以硅藻土、γ-AL_2O_3和MgO为载体,采用均相沉淀-超声浸渍法,制备用于1,2-环己二醇脱氢制备邻苯二酚的镍基催化剂,利用SEM和BET对催化剂进行表征,并对催化活性和选择性进行考察。研究表明,超声浸渍法制备的催化剂,表观形貌规整,颗粒大小均匀,具有较大比例利于生成邻苯二酚的中孔结构,表现出良好的活性和选择性。在超声频率28 kHz、超声声强300 W·m^(-2)和超声时间60 min制备的Ni/硅藻土催化剂,于320℃、101.3 kPa、空速2.4 h^(-1)、N_2流量30 mL·min^(-1)和n(1,2-环己二醇):n(水)=1:4条件下反应,1,2-环己二醇转化率达96.7%,邻苯二酚选择性为92.3%。

Using diatomite,γAl2O3 and MgO as the supports,nickelbased catalysts for dehydrogenation of 1,2cyclohexandiol to catechol were prepared by homogeneous precipitationultrasonic impregnation method and characterized by SEM and BET.The catalytic activity and selectivity of the catalysts were investigated.The results showed that catalysts prepared by ultrasonic method had regular porosity,uniform particle size and large mesopore structures which were beneficial to improve selectivity to catechol,and exhibited good activity and selectivity.1,2Cyclohexandiol conversion of 96.7% and the selectivity to catechol of 92.3% were attained over Ni/diatomite catalyst treated under ultrasonic with the frequence of 28 kHz and the intensity of 300 W·m-2 for 60 min,and under the reaction condition of 320 ℃,101.3 kPa〖JP〗,space velocity 2.4 h-1,N2 flow rate 30 mL·min-1and n（1,2cyclohexanediol）∶n（H2O）=1∶4.