Ascorbic Acid/Fe@Fe2O3: A Highly Efficient Combined Fenton Reagent to Remove Organic Contaminants

摘要：

　　In this study,we demonstrate that the combination of ascorbic acid and Fe@Fe2O3 core-shell nanowires (AA/Fe@Fe2O3) offers a highly efficient Fenton reagent.This combined Fenton reagent exhibited extremely high activity on the decomposition of H2O2 to produce ·OH for the degradation of various organic contaminants,including rhodamine B,methylene blue,alachlor,atrazine,siduron,lincomycin,and chloroamphenicol.The contaminant degradation constants in the AA/Fe@Fe2O3/H2O2 Fenton systems were 38-53 times those in the conventional homogeneous Fenton system (Fe(Ⅱ)/H2O2) at pH 3.8.Moreover,the ·OH generation rate constant in the AA/Fe@Fe2O3/H2O2 Fenton system was 1-3 orders of magnitudes greater than those of heterogeneous Fenton systems developed with other iron-containing materials (α-FeOOH,α-Fe2O3,FeOCl,and so on).The high activity of AA/Fe@Fe2O3 was attributed to the effective Fe(Ⅲ)/Fe(Ⅱ) cycle and the iron-ascorbate complex formation to stabilize ferrous ions with desirable and steady concentrations.During the AA/Fe@Fe2O3/H2O2 Fenton process,aseorbic acid served as a reducing and complexing reagent,enabling the reuse of Fe@Fe2O3 nanowires.We systematically investigated the alachlor and ascorbic acid degradation and found that they could be effectively degraded in the AA/Fe@Fe2O3/H2O2 system,accompanying with 100% of dechlorination and 92% of denitrification.Gas chromatogram-mass spectrometry was employed to identify the degradation intermediates of alachlor and ascorbic acid for us to propose their possible degradation mechanisms.This study sheds light on the importance of Fe(Ⅲ)/Fe(Ⅱ) cycle for the design of high efficient Fenton system and provides an alternative pathway for the organic contaminants removal.For instance,the combination of ascorbic acid or sodium ascorbate and Fe@Fe2O3 nanowires offers a highly efficient Fenton reagent for potential wastewater treatment in a broad working pH range of 3.8-7.0.

关键词： Fe@Fe2O3 Core-Shell Nanowires Ascorbic Acid Alachlor Degradation Fenton Reaction

作者: HOU Xiaojing HUANG Xiaopeng AI Zhihui ZHANG Lizhi ZHAO Jincai

作者单位: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental Chemistry, Central China Normal University, Wuhan 430079, P.R.China

会议类型: 国际会议

会议名称: 2015 International Symposium on Environmental Science and Technology (2015 ISEST)(2015环境科学与技术国际会议)

会议地点: 重庆

会议语种:英文

页码: 45-49

在线出版日期: 2015-11-18（万方平台首次上网日期，不代表论文的发表时间）