CeO_2稳定Ru/γ-Al_2O_3湿空气氧化催化剂的研究

Investigation on CeO_2 Stabilized Ru/γ-Al_2O_3 Catalyst for Wet Air Oxidation Process

用 Ce O2 作添加剂 ,对以 γ- Al2 O3为载体、Ru O2 为活性组分的 Ru/ Al2 O3湿空气氧化催化剂掺杂改性 ,用分步浸渍的方法制备出 Ru/ Ce O2 / Al2 O3三元复合氧化物催化剂 .经 XRD分析 ,证明 Ce O2 进入了 γ- Al2 O3的晶格 ,并且有效抑制了高温时 γ- Al2 O3向 α- Al2 O3的相变及 Ru O2 向 γ- Al2 O3晶格的渗入 .在 2 70℃、 5 .5 MPa条件下 ,对苯酚的催化氧化降解结果表明 ,Ce O2 的加入可明显提高催化剂活性 ,其中 Ru∶ Ce O2 ∶ Al2 O3(质量比 ) =0 .6∶ 6∶ 10 0的催化剂性能最佳 ,反应 30 m in,苯酚的去除率为 96 .1% .

Cerium dioxide (CeO\-2) was selected as a kind of additive to modified Ru/Al 2O 3 catalysts which consists of ruthenium oxide (RuO\-2) as active component and γ \|Al 2O 3 as support for wet air oxidation process. A kind of composite oxide catalyst Ru/CeO\-2/Al 2O 3 was prepared by soakage method. XRD was applied to analyze the structure of the catalysts. Results showed that CeO\-2 had been doped into the crystal structure of γ \|Al 2O 3. It was also proved that CeO\-2 can effectively inhibit γ \|Al 2O 3 transforming to α \|Al 2O 3 and also inhibit RuO\-2 doping into the crystal structure of γ \|Al 2O 3. Catalytic wet air oxidation of phenol at high temperature (270 ℃) and high pressure (5.5 MPa) was studied. The catalysts modified by CeO\-2 showed more catalytic activity than Ru/Al 2O 3 catalysts. The catalysts with the ratio of Ru∶CeO\-2∶Al 2O 3 of 0.6∶6∶100 exhibited excellent catalytic activity. The conversion of phenol was 96.1% after 30 min degradation.