臭氧氧化-光催化降解水中的五氯酚

Degradation of Pentachlorophenol in Aqueous Solution by Ozonation-Photocatalysis

利用臭氧氧化-光催化技术降解水中的有机污染物五氯酚(PCP)。对比了紫外光照射、臭氧氧化、光催化、臭氧氧化-光催化4种方法降解PCP的情况。考察了臭氧氧化-光催化体系中臭氧流量、臭氧产量、PCP初始质量浓度、pH和CO23-等因素对PCP降解率的影响。实验结果表明,臭氧氧化-光催化法比单独使用紫外光照射、臭氧氧化、光催化法更能有效的去除PCP;增加臭氧流量和臭氧产量有利于提高PCP的降解率;降低PCP的初始浓度,PCP的降解率显著提高;pH对PCP的降解效果影响不明显;CO23-的存在显著降低了PCP的降解率。在臭氧氧化-光催化体系中,除臭氧直接氧化降解PCP外,臭氧与TiO2协同作用产生的.OH对PCP的降解也起到了重要作用。

Study of pentachlorophenol（PCP） degradation in aqueous solution was carried out by UV illumination, ozonation, TiO2/UV photocatalysis and ozonation - TiO2/UV photocatalysis separately. The ozonation - TiO2/UV photocatalysis process of PCP degradation was the most efficient among the four. Effects of ozone flow rate, ozone output, initial mass concentration of PCP, initial pH and carbonic acid radicals of PCP solution on degradation ratio of PCP in ozonation - TiO2/UV photocatalysis were investigated. The degradation ratio of PCP rises with increase of ozone flow rate and ozone output, and with decrease of initial mass concentration of PCP. The effect of initial pH on degradation ratio is not obvious. The presence of carbonate significantly reduces the degradation ratio of PCP, but the generated hydroxyl radicals significantly promote PCP degradation.