二氧化氯预氧化对三氯乙醛前体物的去除与机制研究

以我国南方某水源水为研究对象,研究不同二氧化氯投加量下三氯乙醛(CH)前体物的去除情况,并对其去除机制进行分析.结果表明:当二氧化氯投加量为0.4 mg·L~(-1)时,CH生成势(CHFP)去除率最高,为14.3%,同时比CH生成势(SCHFP)亦有大幅削减,且二氧化氯预氧化对浊度和SUVA_(254)亦有较好的去除效果,但对COD_(Mn)去除效果不明显,DOC、UV_(254)则有小幅上升.二氧化氯去除CH前体物的机制是通过将含C=C双键和C=O双键的不饱和芳香性蛋白质类及微生物代谢产物类亲水性物质氧化降解或转化为其他非CH前体物的物质,从而使CH的生成量减少.

Efficiency and mechanism of removing chloral hydrate precursor by chlorine dioxide preoxidation

Removal of chloral hydrate (CH) precursor under the different chlorine dioxide dosages was researched for a drinking water source in the south of China, at the same time, removal mechanism was analyzed. The results indicated that under the chlorine dioxide dosage of 0.4 mg·L^-1, the removal rate of chloral hydrate formation potential (CHFP) was the highest, namely, 14.3%, and the special chloral hydrate formation potential (SCHFP) was significantly reduced. In addition, chlorine dioxide preoxidation also had high removal rate for turbidity and SUVA₂₅₄, and unobvious removal rate for COD_Mn, whereas DOC, UV₂₅₄ slightly increased. The mechanism that chlorine dioxide was used to remove CH precursors was that unsaturated aromatic proteins, containing C=C double bonds and C=O double bonds, and microbial metabolites were degraded oxidatively or converted to other non-CH precursors to reduce the formation of CH.