铜对钌改性尖晶石催化剂结构和氧化性能的影响

Influence of Cu Additive on the Structure of Ru-modified Spinel Catalyst and Its Oxidative Performance

通过湿化学法制备钌改性的纳米尖晶石MnFe_(1.95)Ru_(0.05)O_4催化剂,考察了添加助剂铜对该催化剂的影响通过比表面积和孔径分布表征结果证实,铜助剂的添加有效地增大了比表面积和孔容.XPS的测试结果表明,钌的改性大大改变了尖晶石中各元素如锰和铁的化学环境;助剂铜的添加对于锰和铁等原子的影响不大,但对钌原子的影响显著;EXAFS表征结果显示了铜助剂的导入影响了钌的周围环境,形成了活性Ru=0键.以桂皮醇和苯甲醇的氧化反应为典型反应考察了添加助剂铜前后的影响.

Nanoparticle spinel MnFe1.95Ru0.05O4 catalyst was prepared via wet chemical method and the influence of Cu additive on this catalyst was investigated. The specific surface area and pore volume of the catalyst were increased by adding Cu additive. The results of XPS demonstrate that the chemical environment of elements such as Mn and Fe was greatly influenced by Ru modification while hardly influenced by Cu additive; however, the chemical environment of Ru was affected by Cu additive. The results of EXAFS characterization demonstrate the newly formed active Ru = 0 bond, which is attributed to Cu additive. The influence of Cu additive on catalytic activity was studied using the oxidations of cinnamyl alcohol and benzyl alcohol as typical reactions.