%0 Journal Article
%T Dechlorination Degradation of 2,4-D by Nanoscale Fe3O4<br>纳米四氧化三铁对2,4-D的脱氯降解
%A FANG Guo-dong
%A SI You-bin
%A <br>方国东
%A 司友斌
%J 环境科学
%D 2010
%I 
%X Reductive transformation of 2,4-Dichlorophenoxyacetic acid (2,4-D) by nanoscale Fe3O4 was studied, and the effects of 2,4-D initial concentration, the dosage of nanoscale Fe3O4, pH and temperature on degradation rate of 2,4-D were investigated. The results showed that 48% 2,4-D with initial concentration of 10 mg/L was transformed within 48 h in the presence of 300 mg/L nanoscale Fe3O4. The degradation of 2,4-D was a reductive dechlorination process, and the concentration of chloride ion increased sharply with the degration of the 2,4-D. Disappearance of parent species and formation of reaction intermediates and products were analyzed by LC/MS. The transformation of 2,4-D followed a primary pathway of its complete reduction to phenol and a secondary pathway of sequential reductive hydrogenolysis to 2,4-dichlorophenol (2,4-DCP), 4-chlorophenol (4-CP) or 2-chlorophenol (2-CP) and phenol. The degradation equations of 2,4-D by nanoscale Fe3O4 conformed to pseudo-first-order kinetics, and the reaction rate constant (K) of 4-CP, 2,4-DCP and phenol were 0.0043 h-1, 0.0026 h-1 and 0.0032 h-1, respectively. The degradation rate increased with an increase in initial concentration of 2,4-D from 0 mg/L to 10 mg/L, and increasing the dosage of nanoscale Fe3O4 from 0 mg/L to 300 mg/L. The pH of reaction solution significantly influenced reductive degradation of 2,4-D, and the optimum pH value was 3.0. Besides, high temperature could improve dechlorination rate of 2,4-D.
%K 2
%K 4-D<br>纳米Fe3O4
%K 脱氯降解
%K 动力学
%K 降解产物
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=3FF3ABA7486768130C3FF830376F43B398E0C97F0FF2DD53&cid=A7CA601309F5FED03C078BCE383971DC&jid=64CD0AA99DD39F69401C615B85F123EF&aid=7A9D7B7F9FBEE19F83A6D3F48B4CDA3B&yid=140ECF96957D60B2&vid=4AD960B5AD2D111A&iid=B31275AF3241DB2D&sid=D56713C22DA9FDE8&eid=CAF3E71A6764366D&journal_id=0250-3301&journal_name=环境科学&referenced_num=2&reference_num=22