孙东 沈莉萍 张志鹏 曹楠 熊亭亭 龚正君

摘 要：随着铬工业化利用的发展，铬污染问题日益严峻。基于金属网易分离的优势，采用化学沉积法制备Al/Cu双金属网材料，实现对Cr（Ⅵ）的快速去除，并通过静态试验系统优化了反应温度、溶液pH值、Al/Cu双金属网投加量等条件。对Al/Cu双金属网材料进行表征，发现Cu涂覆呈现疏松的珊瑚状颗粒原位生长在铝网表面;Cr（Ⅵ）去除的静态试验表明，在较大的pH值（3.0～9.0）范围内Al/Cu双金属网对Cr（Ⅵ）的去除率可达到90%以上;当Al/Cu双金属网的投加量为3片、Cr（Ⅵ）初始浓度5 mg/L、反应温度40 ℃时，对水中Cr（Ⅵ）的去除效果最佳。机理分析表明：Al/Cu双金属网表面形成大量的电偶原电池，促进Al0的腐蚀，释放电子将Cr（Ⅵ）还原为Cr（Ⅲ）;双金属网表面[H]abs的产生进一步促进对Cr（Ⅵ）的还原，生成Cr（OH）3或以絮凝物的形式沉积在双金属网表面，达到从水溶液中去除Cr（Ⅵ）的目的。易分离的Al/Cu双金属网有助于实现地下水等水体中Cr（Ⅵ）的快速去除，具有良好的工程应用前景。

关键词：化学沉积法;铝铜双金属网;六价铬;废水处理

中图分类號：X703.5 文献标志码：A 文章编号：2096-6717（2021）06-0180-07

Abstract： With the development of industrial utilization of chromium， the problem of chromium pollution is becoming more and more serious. Based on the advantages of easy separation of metal mesh， Al/Cu bimetallic mesh materials were prepared by chemical deposition method to realize the rapid removal of Cr（Ⅵ）. Thereaction temperature， solution pH， Al/Cu bimetallic dosing quantity and other conditions were optimized by static test system. The Al/Cu bimetallic mesh material was characterized. It was found that the loose coral-like particles of Cu coating grew on the surface of the Al mesh in situ. The static test of Cr（Ⅵ） removal showed that the removal rate of Cr（Ⅵ） by Al/Cu bimetallic network can reach more than 90% in a wide pH range of 3.0～9.0.When the dosage of Al/Cu bimetallic network was 3 pieces， the Cr（Ⅵ） initial concentration was 5 mg/L， and the reaction temperature was 40 ℃， the removal effect of Cr（Ⅵ） in water worked best.Mechanism analysis showed that a large number of galvanic cells were formed on the surface of Al/Cu bimetallic network to promote Al0 corrosion and release electrons to reduce Cr（Ⅵ） to Cr（Ⅲ）.The formation of[H]abs on the surface of bimetallic mesh further promoted the reduction of Cr（Ⅵ） to Cr（OH）3 or deposits in the form of flocs on the surface of bimetallic network to remove Cr（Ⅵ） from aqueous solution.The easily separated Al/Cu bimetallic mesh is helpful for the rapid removal of Cr（Ⅵ） in groundwater and other water bodies， and has a good prospect of engineering application.

Keywords：chemical deposition; aluminum copper bimetallic mesh; hexavalent chromium; wastewater treatment

Cr（Ⅵ）是一种有毒重金属形态[1]，具有高毒性、高可溶性、极易迁移性和不可生物降解性[2]，甚至有诱发癌症、致突变和致畸等广泛的危险特性[3]，其在冶金、电镀和皮革等工业领域被广泛应用并排入环境中，给人类生存带来极大的威胁[4]。目前已采用各种方法从水体中去除Cr（Ⅵ），如化学沉淀、吸附、膜过滤和光催化还原[5-6]等。其中，吸附和化学还原的协同作用被认为是最经济有效的方法之一，因为它操作简单、无污泥、可再生，且对Cr（Ⅵ）具有更高效的去除效果[7]。……