根据氯代硝基苯的氯取代基和硝基取代基特性，考察零价铁对水中4-氯硝基苯（4-ClNB）的处理效果，推测ZVI降解4-ClNB的反应途径及影响因子。结果表明，零价铁将4-ClNB首先还原为4-氯亚硝基苯（4-ClNSB），最终还原产物为4-氯苯胺（4-ClAN）；4-ClNB还原转化速率和产物生成速率在酸性到中性条件下随pH值减小而增快，pH值大于7达到12时，4-ClNB还原转化速率急剧下降；反应过程中铁的腐蚀产物Fe2+浓度在pH值为3时较大，偏碱性条件下由于络合生成Fe（OH）2，溶液中几乎检测不到Fe2+；ZVI降解4-ClNB的还原转化率随4-ClNB初始浓度的增加而减小，随ZVI投加量的增加而增加，但最后反应速率趋于稳定；废水中NH4+、NO3-等共存离子可以促进4-ClNB的还原转化速率。%Based on the properties of chlorine substituents and nitro substituents of chloronitrobenzene, the treatment effects on 4-Nitrochlorobenzene (4-ClNB) by zero-valent iron were investigated, and the degradation path and impact factors were conjectured. The results showed that 4-ClNB was firstly reduced to 4-chloride and nitrobenzene, and finally reduced to 4-chloroaniline. In acidic to neutral conditions, the reductive transformation rate of 4-ClNB and production formation rate decreased quickly with increasing pH value. When pH was greater than 7, the reductive transformation rate of 4-ClNB was sharply declined. The concentration of Fe2+, the corrosion products of iron, was highest when pH was 3. In alkaline condition, Fe2+ was almost not detected in solution due to the complex formation of Fe(OH)2. The reductive transformation rate of 4-ClNB decreased and rose respectively with the initial concentration of 4-ClNB and the dosage of ZVI increasing, and then tending to be stable. NH4+, NO3-and other coexisting ions had promotion on the reductive transformation rate of 4-ClNB.
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