纳米四氧化三铁对2,4-D的降解研究

Degradation of 2,4-D by Nano-scale Fe_3O_4

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%。

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.