稀土金属铈对湿式氧化催化剂性能的影响

EFFECTS OF RARE EARTH METAL CERIUM IN THE CATALYSTS FOR CATALYTIC WET AIR OXIDATION ON ITS PERFORMANCE

采用浸渍沉淀法制备具有相同Cu负载量的CuO/γ Al2 O3,CuO CeO2 /γ Al2 O3和CuO ZnO CeO2 /γ Al2 O3催化剂 ,用H酸配水的催化湿式氧化评价催化剂的性能 .结果表明 ,稀土元素Ce作为活性成分 ,不仅可以显著加快初期的反应速率 ,而且也增加了第二阶段的反应速率 ;还能提高反应中间产物小分子羧酸的降解速度和反应终了的pH值 ,从而减少金属铜的溶出 ;掺杂Ce使催化剂的晶体大小和孔隙分布更为均匀 ,孔径增大 。

CuO/ γ Al 2O 3,CuO CeO 2/ γ Al 2O 3 and CuO ZnO CeO 2/ γ Al 2O 3 complex oxide catalysts for catalytic wet air oxidation of H acid as model reactant were prepared by dipper precipitation me thods .The presence of Ce in the catalysts had promotion effect on the activity of the catalyst,increased the degradation speed of small molecule carboxylic acids,which were the intermediate pro ducts of catalytic wet air oxidation process,and raised the pH of ultimate reaction solution,decreased leaching amount of Cu in the catalysts.The rare earth element Ce could uniform size of crystals and distribution of pore and increased the size of pore in the catalysts.The doping Ce in catalysts improved the catalytic activity and stability.