硫酸钠对Ni/硅藻土催化剂结构及脱氢性能的影响

Effect of Na_2SO_4 on Structure and Catalytic Performances of Ni/Diatomite for the Catalytic Dehydrogenation of 1,2-Cyclohexanediol

通过均相沉淀法制备了负载型Ni/硅藻土催化剂前驱体,采用等体积浸渍法添加了助剂Na2SO4,并采用BET比表面积测试法、X射线衍射(XRD)、X射线光电子能谱分析(XPS)和程序升温还原法(H2-TPR)等技术对催化剂的比表面积、物相结构、表面组分价态及含量以及氧化还原性能进行了表征,考察了Na2SO4对催化剂结构及脱氢反应性能的影响。结果表明,添加Na2SO4,载体硅藻土中SiO2的晶型未发生转变,提高了Ni物种在催化剂表面的分散度,显著提高了1,2-环己二醇的转化率(95.1%)和目标产物邻苯二酚的选择性(91.4%)。

The catalytic dehydrogenation of 1,2-cyclohexanediol to catechol was examined on Ni-Na2SO4/ diatomite, and technologies such as BET, X-Ray Diffraction （XRD）, X-ray Photoelectron Spectroscopy （XPS） and Temperature-Programmed Reduction （H2-TPR） were used to characterize the specific surface area, phase structure, surface component valence state and redox performance of the catalysts. Moreover, the influences of Na2SO4 on catalyst structure and dehydrogenation reaction performance were investigated. The results show that adding Na2SO4 to Ni/diatomite can improve the dispersion of Ni species on the catalyst surface without changing the crystal form of SiO2, which may enhance the conversion rate （95.1%） of 1,2-cyclohexanediol and selectivity of target product-catechol （91.4%）.