中文摘要：

采用纳米Fe3O4降解溶液中的2，4-D，考察了2，4-D初始浓度、纳米Fe3O4的投加量、溶液pH对2，4-D降解效率的影响，并探讨了2，4-D的降解机理。实验结果表明，Fe3O4对2，4-D有明显的降解作用，纳米Fe3O4的降解效果优于微米级Fe3O4，降解过程中溶液中的氯离子浓度随着2，4-D的降解而升高，Fe3O4对2，4-D的降解机理是还原脱氯。当2，4-D初始浓度在0-10mg／L、纳米Fe3O4投加量0-300mg／L的范围内，2，4-D降解率随初始浓度和纳米Fe3O4投加量的增加而增大。在2，4-D初始浓度为10mg／L、pH3．0、纳米Fe3O4投加量300mg／L时降解效率最高，48h内2，4-D的降解率可达40％。

英文摘要：

Nano-scale Fe3O4 was used to degrade 2, 4-D in aqueous solution. Results showed that initial concentration of 2, 4-D, pH and nano-scale Fe3O4 dosage were important factors for the degradation of 2, 4-D. It was found that the decomposition efficiency of 2, 4-D by nano-scale Fe3O4 was higher than micro-scale Fe3O4, and the concentration of chlorine ion increased with degradation of 2, 4-D. It suggested that the degradation mechanism of 2, 4-D was reductive dechlorination. Degradation of 2, 4-D increased with increase of initial concentration of 2, 4-D of 0-10mg/L and nano-scale Fe3O4 dosage of 0-300mg/L. 40% of 2, 4-D could be degraded after 48h with 300mg·L^-1 nano-scale Fe3O4, at pH of 3 and initial concentration of 2, 4--D 10mg/L.