Cu-Fe-Ru-La/γ-Al_2O_3湿式氧化催化剂的制备、表征及机理(英文)

Preparation,Characterization and Mechanism of Cu-Fe-Ru-La/γ-Al_2O_3 Catalysts for Wastewater Wet Oxidation

采用等量浸渍法以γ-Al2O3为载体,制备过渡金属Cu和Fe、贵金属Ru、稀土金属La的复合催化剂。采用催化湿式空气氧化法处理模拟印染废水,研究金属离子配比、焙烧温度对催化剂活性及稳定性的影响,并对催化剂CWAO反应机理进行探讨:权衡催化剂的活性和稳定性,催化剂的组分质量配比和焙烧温度分别为Cu∶Fe∶Ru∶La=1∶1∶1∶3、450℃。对催化剂进行XRD、XPS、孔结构、FT-IR、TG-DTA、SEM、TEM表征,结果表明:焙烧使催化剂组成物质分解为氧化物,元素Cu、Fe、Ru、La分别以CuO、Fe2O3、RuO2、La2O3形式存在;焙烧温度升高,晶粒长大结晶趋于完整,催化剂孔容孔径增大但比表面积减小,晶粒尺寸分布在5～20 nm;Cu-Fe-Ru-La/γ-Al2O3催化剂使用前后结构无明显变化且反应后溶出的金属浓度低,催化剂具有较高的稳定性。

Composite catalysts,consisting of transition metals Cu and Fe,precious metal Ru,rare earth La,and a γ-Al 2 O 3 carrier,were prepared using the isometric impregnation method.Simulated wastewater was treated by catalytic wet air oxidation（CWAO）,and the effects of catalytic metal ion ratios and calcination temperature on the catalytic activity and stability of the prepared catalysts were studied.In addition,the CWAO reaction mechanism was explored.Considering catalyst activity and stability,the optimal composition of the catalyst was found to be Cu∶ Fe∶ Ru∶ La = 1∶ 1∶ 1∶ 3,and the optimal calcination temperature was found to be 450 ℃.Material characterization using XRD,XPS,pore structure analysis,FT-IR,TG / DTA,SEM,and TEM showed that the catalyst composition was decomposed into oxides,such that elements Cu,Fe,Ru,and La existed in the forms of CuO,Fe 2 O 3,RuO 2,and La 2 O 3,respectively.As calcination temperature was increased,crystal grains grew larger and tended to be more complete,pore volumes and pore sizes of the catalyst became bigger,but its specific surface area was reduced;overall grain sizes were between 5 to 20 nm.The Cu-Fe-Ru-La / γ-Al 2 O 3 catalyst showed no significant changes before and after use,and contained low concentrations of dissolved metals after the reaction,indicating that the catalyst was highly stable.