摘要
为提高电絮凝法对Ni-EDTA的去除效率,并深入分析其反应机理,研究了不同材料的电极组合、电流密度和初始p H对Ni-EDTA去除效果的影响。结果表明:铁阳极+铝阴极产生的有效絮凝剂最多,对TOC和Ni的去除率最高,分别为98.75%和99.99%;随着电流密度的增大,TOC和Ni的去除率逐渐升高,4.38 m A·cm^(-2)时去除率分别达到98.95%和99.21%;且电流效率开始下降。初始p H为3时,TOC和Ni的去除率分别为98.27%和99.89%,随着p H的升高去除率逐渐下降。对溶液和絮体进行紫外光谱(UV)、红外光谱(FTIR)以及扫描电镜(SEM-EDS)分析结果表明:Ni-EDTA主要通过Fe(OH)_3的絮凝吸附沉淀,电解产生的HClO和阳极电位的氧化反应以及Fe(Ⅲ)的转络合反应等一系列共同作用去除。
In order to improve the removal efficiency of Ni-EDTA and analyze the reaction mechanism, electro-coagulation treatment of Ni-EDTA complexes wastewater was conducted in reactor and the effect of parameters such as electrode arrangement, current density and initial pH on the Ni-EDTA removal were investigated systematically. The results showed that the best performance, with 98. 75% removal for TOC and 99. 9 % removal for Ni, were achieved by using the combination of Fe anode and Al cathode which produced the most effective flocculant. The performace of the electro-coagulation was enhanced by increasing current density with removal efficiency up to98. 95% for TOC and 99. 21% for Ni achived, respectively, under current density of 4. 38 mA-cm-2. The optimal performance of the electro-coagulation were obtained at initial pH 3 under which 98.27% removal for TOC and99. 89% removal for Ni were achieved, respectively, after that, the removal rate gradually decreased with the increases of pH. The solution and flocculation were analyzed by ultraviolet spectrum （ UV） , infrared spectrum （ FT- IR） and scanning electron microscope （SEM-EDS） which indicated that precipitation by flocculation of Fe（OH）3, oxidation by HCIO with anode and trans-complexation of Fe（ IH ） were responsible for the removal of Ni-EDTA bythe electro-coagulation process.
出处
《科学技术与工程》
北大核心
2017年第15期150-156,共7页
Science Technology and Engineering
基金
广东省教育厅自然科学项目(2015KTSCX140)
2016年大学生创新创业训练计划省级项目(201611819053)资助
关键词
电絮凝
Ni-EDTA
络合
絮凝
沉淀
electro-coagulation Ni-EDTA complexation flocculation precipitate
