电解法处理高浓度含铬废水回收铬的研究  

Electrolysis treatment of sewage-containing high-concentrated chromium

作　　者：雷英春[1] 

机构地区：[1]太原工业学院环境与安全工程系,太原030008

出　　处：《安全与环境学报》2011年第6期43-45,共3页Journal of Safety and Environment

摘　　要：采用电解法处理Cr(Ⅵ)质量浓度为2.6～10.4g/L的废水,研究电解电流、电解时间、NaCl、H_2SO_4对去除率的影响。结果表明,NaCl可以增加溶液电导率,Clˉ可以穿透阴极表面生成的致密Cr(OH)_3膜,从而降低阴极极化,同时活化铅阳极表面形成的PbO_2膜,降低阳极极化。溶液中加入NaCl可以提高Cr(Ⅵ)去除率。最佳工艺条件为:Cr(Ⅵ)质量浓度7.8g/L,电解电流1.4 A,电解时间10 min,NaCl添加量2 g,H_2SO_4添加量2 mL,温度25℃。此时Cr(Ⅵ)去除率为99.9%。The paper aims to introduce the author＇s work on the electrolysis treatment of chromium-containing sewage. The sewage adopted in the paper was prepared by CrO3 （made with analytic grade AR） and distilled water, with the content of Cr（Ⅵ） being 2.6-10.4 g/L, treated with 1,5-diphenylcarbahydrazide spectrophotometric method. The electrolysis cell we adopted was made up of polymethyl methacrylate, and the insoluble anode was made of pure lead, whereas the cathode was made up of stainless steel. In our research, we have also studied the influence of such factors on the removal rate, such as the chromium concentration of chromium-containing sewage, the electrolysis current intensity, the electrolysis time, as well as the added medicament, for example, the sodium chloride and sulfuric acid. The above experiments help us to find that, firstly, with the increase of the concentration of Cr（Ⅵ） in the artificial sewage, the removal rate tends to increase accordingly. However, under the concentration value of 10.4 g/L, it is required to reduce Cr（Ⅵ） to Cr（Ⅲ） in the sewage because the removal rate of Cr（Ⅵ） tends to decrease; secondly, the increase of the electrolysis current intensity implies enormour investment, especially, for the cost of equipment purchase. Therefore, it is necessary to keep the electrolysis current intensity at the moderate level; thirdly, though it is possible to increase the high removal rate by prolonging the electrolysis time, it also brings the trouble to prolong the unit operation time. And, finally, Cl- is likely to penetrate the non-conducting membranes and lead Cr（OH）3 to adhere to the surface of cathode and in turn reduce the cathodic polarization. Besides, we have also studied the best technology conditions, that is： the removal rate of Cr（Ⅵ） is 99.9% under the optimal conditions.

关 键 词：环境工程学 电解法 高浓度含铬废水 去除率 正交试验 最佳工艺条件 

分 类 号：X703.1[环境科学与工程—环境工程]