水溶液中铁与三氯乙醛的还原脱氯反应实验研究

Study on reductive dechlorination of trichloroacetadehyde by iron in water

针对零价铁可以有效清除工业废水中低浓度的有机氯化物,在实验中考察了铁粉对三氯乙醛的脱氯效果,重点探讨了反应时间、三氯乙醛质量浓度、pH值等因素对脱氯率的影响。实验结果表明,还原铁粉对三氯乙醛有明显的脱氯作用,脱氯率随三氯乙醛质量浓度的减小而增大,随pH值的减小而增大,随反应时间的增加而增大。在厌氧条件下,三氯乙醛质量浓度为51.5 mg/L和103 mg/L,反应前pH=2.0,反应时间为3 h时,脱氯率可以分别达到70%和61%。脱氯机理主要是基于零价铁的还原作用。

Recently, people have realized that zero-valent iron can eliminate chlorinated organic compounds with low concentration in the groundwater, so the dechlorination of chloral with iron particles in water was studied in the experiment. The effects of the reaction time, the concentration of chloral and the pH on dechlorination were obtained, and the results showed that the dechlorinate effect was obvious. The dechlorination efficiency of chloral increased with the decrease of the chloral concentration snf yhr pH and the increase of the neaction time. It was found that the dechlorination efficiency can go up to 70% and 61%, when the reaction was run under anaerobic condition for 3 hours （pH = 2.0） with the concentrations of chloral at 51.5 and 103 mg/L respectively. The mechanism of the dechlorination is based on the reduction of the zero-valent iron.