H_(2)O_(2)/NaClO协同体系对废水中次磷酸盐的处理效果及氧化机制  

Performance and oxidation mechanism of H_(2)O_(2)/NaClO synergistic system on hypophosphite treatment in wastewater

作　　者：郭振杰 李一兵 刘雪瑜[1] 张静 赵旭[3] 黎佳茜 温硕钊 张娟娟 GUO Zhenjie;LI Yibing;LIU Xueyu;ZHANG Jing;ZHAO Xu;LI Jiaqian;WEN Shuozhao;ZHANG Juanjuan(Institute of Water Ecology and Environmental,Chinese Research Academy of Environmental Sciences,Beijing 100012;School of Civil and Transportation Engineering,Hebei University of Technology,Tianjin 300401;Key Laboratory of Drinking Water Science and Technology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085)

机构地区：[1]中国环境科学研究院,水生态环境研究所,北京100012 [2]河北工业大学土木与交通学院,天津300401 [3]中国科学院生态环境研究中心,饮用水科学与技术重点实验室,北京100085

出　　处：《环境工程学报》2024年第3期727-736,共10页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金青年科学基金资助项目(22106173)。

摘　　要：本研究以废水中的次磷酸盐(H_(2)PO_(2)^(-))为目标污染物,比较了过氧化氢(H_(2)O_(2))、次氯酸钠(NaClO)和H_(2)O_(2)/NaClO协同体系对H_(2)PO_(2)^(-)的处理效果。结果表明,H_(2)O_(2)/NaClO协同体系的处理效果最优,能够实现有效氧化H_(2)PO_(2)^(-)生成PO_(4)^(3-)。利用自由基淬灭实验和电子自旋共振波谱(ESR)分析发现,该体系中ClO^(-)、·OH、·O_(2)^(-)和1O2是体系氧化H_(2)PO_(2)^(-)的活性物种,其中1O2起主要作用。详细探究了H_(2)O_(2)浓度、NaClO浓度、初始溶液pH、共存无机阴离子(SO_(4)^(2-)、NO_(3)^(-)、HCO_(3)^(-)、Cl^(-))、共存有机阴离子柠檬酸根(C6H5O73-)和腐殖酸(HA)对反应体系氧化H_(2)PO_(2)^(-)为PO_(4)^(3-)效率的影响。当H_(2)O_(2)和NaClO投加量均为50 mmol·L^(-1),初始溶液pH为5,反应120 min时,1 mmol·L^(-1)H_(2)PO_(2)^(-)氧化为PO_(4)^(3-)的生成率为88%。该反应体系中SO_(4)^(2-)、NO_(3)^(-)、HCO_(3)^(-)和Cl^(-)对H_(2)PO_(2)^(-)的氧化去除无明显影响,但C_(6)H_(5)O_(7)^(3-)和HA的存在对H_(2)PO_(2)^(-)的氧化去除有抑制作用。通过在酸性介质(pH<4.3)下将Fe^(3+)添加到生成的PO_(4)^(3-)废水中以形成FePO_(4)沉淀物,实现磷在废水中去除同时回收磷。最后,验证了该体系对含H_(2)PO_(2)^(-)实际废水处理的可行性。以上研究结果可以为含H_(2)PO_(2)^(-)的工业废水处理提供参考。In this study,hypophosphate(H_(2)PO_(2)^(-))in wastewater was selected as the target pollutant.The performance for H_(2)PO_(2)^(-)oxidation to orthophosphate(PO_(4)^(3-))via varies methods including hydrogen peroxide(H_(2)O_(2)),sodium hypochlorite(NaClO)and H_(2)O_(2)/NaClO synergistic system were compared.It was found that H_(2)O_(2)/NaClO synergistic system had the best performance on the oxidation of H_(2)PO_(2)^(-)to PO_(4)^(3-).The radical quenching experiments and electron spin resonance(ESR)spectroscopy results proved that ClO^(-),·OH,·O_(2)^(-)and 1O2 were contributable to the oxidation of H_(2)PO_(2)^(-)to PO_(4)^(3-)in the H_(2)O_(2)/NaClO synergistic system,and the key active species was 1O2.The effects of H_(2)O_(2)concentration,NaClO concentration,initial solution pH,coexisting inorganic anions(SO_(4)^(2-),NO_(3)^(-),HCO_(3)^(-)and Cl^(-)),coexisting organic anions citrate(C6H5O73−)and humic acids(HA)on the oxidation efficiency of H_(2)PO_(2)^(-)to PO_(4)^(3-)by the H_(2)O_(2)/NaClO synergistic system was investigated.The results indicated that the production of PO_(4)^(3-)was 88%at 120 min when the initial concentration of H_(2)PO_(2)^(-)was 1.0 mmol·L^(-1),the dosages of NaClO and H_(2)O_(2)were 50 mmol·L^(-1),and the initial solution pH was 5.In this reaction system,SO_(4)^(2-),NO_(3)^(-),HCO_(3)^(-)and Cl^(-)caused hardly significant effect on the oxidation of H_(2)PO_(2)^(-),while C_(6)H_(5)O_(7)^(3-)and HA concentration could have the inhibitory effects.Finally,phosphorus was recovered via forming FePO_(4)precipitates by adding Fe^(3+)to the generated PO_(4)^(3-)wastewater in an acidic medium(pH<4.3).Finally,the applicability of this system for treatment of actual wastewater containing H_(2)PO_(2)^(-)was confirmed.This study can provide a reference for the treatment of industrial wastewater containing H_(2)PO_(2)^(-).

关 键 词：次氯酸钠 过氧化氢 次磷氧化 正磷酸盐 单线态氧 

分 类 号：X703[环境科学与工程—环境工程]