载Pt石墨催化臭氧化降解水中草酸的研究

Catalytic Ozonation of Oxalic Acid in Water with Pt/Graphite Catalyst

以石墨为催化剂载体,以H2PtCl6.6H2O为贵金属活性组分前驱物,采用等体积浸渍法制备了Pt/石墨催化剂.对Pt/石墨催化臭氧化、石墨催化臭氧化以及单独臭氧氧化降解草酸的效果进行了研究.结果表明,在本实验条件下,单独臭氧氧化、石墨催化臭氧化和Pt/石墨催化臭氧化草酸的去除率分别为3.0%、47.6%和99.3%.Pt的负载可以显著地提高石墨催化臭氧化的效果.以草酸的去除效率为催化活性指标对Pt/石墨催化剂的制备条件进行了优化.结果表明,石墨载体的预处理没有提高Pt/石墨催化剂的活性.Pt/石墨催化剂最佳制备条件为:以水为溶剂,浸渍时间24 h,活性组分Pt的负载量为1.0%,氢还原温度为350℃.所制备催化剂经重复使用5次,草酸去除率仍超过90%.

Pt/graphite catalyst was prepared by incipient wetness impregnation using H2PtCl6·6H2O as precursor substance. The removal efficiencies of oxalic acid by Pt/graphite, graphite catalyzed ozonation and ozonation alone were compared. It was found that the removal efficiency of oxalic acid in ozonatian alone, graphite and Pt/grapliite catalyzed ozonation was 3.0%, 47.6 % and 99.3 % respectively under the present experimental conditions. Results showed that loading of Pt could significantly increase the catalytic activity of graphite. Taking oxalic acid degradation efficiency as indication, the preparation conditions of Pt/graphite were optimized. The pretreatment of graphite had no favor to improve the activity of Pt/graphite catalyst. The optimal preparation conditions of Pt/graphlte catalyst are as follow： impregnant, distilled water; impregnation time, 24 h; the loading amount of Pt, 1.0% ; reduction temperature, 350℃ . The Pt/graphite catalyst was used for five times with no significant decrease of its activity and more than 90% oxalic acid removal was obtained.