| 引用本文: | 陈志强,别旭峰,温沁雪.铁铜微电解处理Cu2+-EDTA溶液及其机理研究[J].哈尔滨工业大学学报,2018,50(8):33.DOI:10.11918/j.issn.0367-6234.201704088 |
| CHEN Zhiqiang,BIE Xufeng,WEN Qinxue.Mechanism of treating Cu2+-EDTA solution by iron-copper microelectrolysis[J].Journal of Harbin Institute of Technology,2018,50(8):33.DOI:10.11918/j.issn.0367-6234.201704088 |
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| 摘要: |
| 电镀废水中常含有EDTA等络合剂，部分重金属呈现络合态，这给重金属的去除带来了极大的挑战.微电解法处理络合废水破络效果好，成本低廉.为此，采用铁铜微电解法处理EDTA络合铜溶液，通过微电解过程的金属离子变化及沉淀物红外光谱分析可知，在微电解过程中主要变化为铁屑溶解、Fe2+和Fe3+质量浓度升高、Cu2+质量浓度降低，并伴随EDTA质量浓度略微下降和Fe(OH)3沉淀生成；采用MINTEQ软件模拟Cu2+、Fe2+和Fe3+与EDTA的络合形态分布，发现加入Fe3+能使EDTA与Cu2+解络，Fe3+与Cu2+摩尔比越大，pH越低，解络效果越好；在碱性条件下加入Fe2+能使EDTA与铜解络.Fe2+与Cu2+摩尔比越大，pH越高，解络效果越好.结合实验和模拟结果可以明确Fe3+在酸性条件下的解络作用和铁屑对游离态Cu2+的还原作用是微电解去除Cu2+-EDTA的主要原因.
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| 关键词: 微电解 EDTA 络合 Visual MINTEQ 破络机理 |
| DOI：10.11918/j.issn.0367-6234.201704088 |
| 分类号:X781.1 |
| 文献标识码:A |
| 基金项目:国家水体污染控制专项(2013ZX07201007-003) |
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| Mechanism of treating Cu2+-EDTA solution by iron-copper microelectrolysis |
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CHEN Zhiqiang,BIE Xufeng,WEN Qinxue
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(State Key Laboratory of Urban Water Resource and Environment(Harbin Institute of Technology), Harbin 150090, China)
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| Abstract: |
| Electroplating wastewater often contains such complex agents as EDTA and some heavy metals exist in complexing form, which present great challenge for heavy metal removal. Given the low cost and satisfying effect of microelectrolytic method in processing complex wastewater, iron-copper microelectrolysis was adopted to treat the EDTA complex copper solution. Analysis of the change of metal ions and the infrared spectrum of the precipitates during microelectrolysis showed that the major changes occurred were iron dissolution, increased concentration of Fe2+ and Fe3+, decreased Cu2+ concentration, accompanied by a slight decrease in EDTA concentration and the formation of Fe(OH)3 precipitate. MINTEQ software was used to simulate the complex morphological distribution. The results show that the addition of Fe3+ can make Cu2+ into a free state. The larger the Fe3+/Cu2+ is, the lower the pH is, hence the better the removal effect. The addition of Fe2+ under alkaline conditions can make Cu2+ become Cu(OH)2. The greater the Fe2+/Cu2+ is, the higher the pH is, the better the removal effect. Combining with the experimental and simulation results, it can be concluded that the desorption of Fe3+ under acidic conditions and the reduction of free Cu2+ by iron scrap are the main reasons for the removal of Cu2+-EDTA by microelectrolysis.
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| Key words: microelectrolysis EDTA complex Visual MINTEQ mechanism |
