氧化剂增强TiO_2纤维光催化降解DMF研究

Study on Oxidant Strengthening Photocatalytic Degradation of DMF over TiO_2 Fiber Catalyst

研究TiO2纤维光催化降解DMF水溶液的结果表明:氧化剂增强了TiO2纤维对DMF的降解能力,在其它反应条件相同情况下,O3/TiO2(F)对DMF降解率是air/TiO2(F)和H2O2/TiO2(F)的1.5倍左右,且降解速率提高2倍左右,COD分析表明DMF几乎完全矿化.同时实验过程中确定了DMF光催化降解中间产物仲胺的存在.以二甲胺为仲胺代表物进行光催化降解研究表明,中间产物仲胺的迅速降解是O3增强TiO2纤维降解效应的主要因素.

Oxidant strengthening the degradation of DMF aqueous solution was investigated when TiO2 fiber is used as the photocatalyst. When the UV light was absent, ozone per se could not make DMF degrade, which proves that DMF is a stable substance. But ozone could increase obviously photocatalytic degradation rate of DMF in O3/TiO2 （F）. Under the same reaction condition, photocatalytic degradation rate and speed of DMF in O3/TiO2（F） was almost 1.5 times and 2 times higher than that in air/TiO2 （F） and H202/TiO2 （F） respectively. COD analysis showed DMF was almost mineralized completely when the reaction was carried out for 120 min. Through Hinsberg test secondary amine was proved as one of intermediates in the process of DMF photocatalytic degradation. Rise of pH value of reaction solution also showed that amine was produced in the photocatalytic reaction process. Degradation speed of DMA in 03/TiO2 （F） was higher than that in air/TiO2 （F）. The increasing degradation rate and speed of DMF was mainly caused by fast degradation of secondary amine in the process of DMF photocatalytic degradation in O3/TiO2（F）.