Kinetic study of 4-chloronitrobenzene degradation by zero-valent iron
零价铁降解4-氯硝基苯动力学研究

4-chloronitrobenzene as a representative material of nitroaromatic compounds was used in this study to investigate the degradation reaction rate and products by different concentrations of zero-valent iron (ZVI) under anoxic condition. According to stoichiometry, different reaction rates of products were obtained by fitting the experimental data. Products of ZVI were measured by M ssbauer technique. The results show that reduction of 4-chloronitrobenzene corresponds to the concentration of ZVI. The production and transformation rates of intermediate products, 4-chloronitrosobenzene and 4-chloro phenyl hydroxylamine, can be achieved. The 4-chloronitrobenzene reduction reaction is the fastest when the ZVI concentration is 1.04 g·L-1. The reaction rate constant is 0.189 min-1. Ferrous iron ions generated during reaction are sorbed on the ZVI surfaces in the early age of the reaction. Formation and reduction reaction rates of different products depend on the reactive sites of ZVI and the mass transfer between each other.