动态隔板电化学反应器处理对硝基氯苯废水研究

The Study on 4-Nitrochlorobenzene Wastewater Treatment by Dynamic Baffled Electrochemical Reactor

以石墨为阴极、钌铱为阳极构建隔板电化学反应器,处理对硝基氯苯(4-CNB)模拟废水。考察了水力循环时间、电流密度、电解质浓度、初始pH等因素对4-CNB还原效果的影响规律;对照了动态方式与静态方式、废水先还原后氧化与直接氧化处理的效果差异。结果表明,当初始4-CNB的质量浓度为50 mg/L,水力循环时间为6 min、电流密度为10 mA/cm^2、电解质Na_2SO_4浓度为50 mmol/L时,还原120 min后对氯苯胺生成率为36.1%,比相同条件下的静态处理效果提高了32.5个百分点。将上述动态方式还原后的废水氧化120 min,废水COD去除率为42.8%,而直接氧化处理120 min废水COD去除率仅为17.1%。

A bench scale experiment was conducted with a baffled electrochemical reactor to treat 4-chloronitrobenzene wastewater, in which graphite electrode was used as the cathode, ruthenium iridium as the anode. The effects of hydranlic cycle time, current density, electrolyte concentration and initial pH on the reduction effect of 4-chloronitrobenzene were studied. The differences between dynamic and static modes, reduction-oxidation and direct oxidation treatments were compared. The results showed that, the production rate of 4-chloroaniline were 36.1% after reduction 120 rain under the conditions with hydraulic residence time of 6 min, current density of 10 mA/cm2 and electrolyte concentration of Na2SO4 and 4-chloronitrobenzene of 50 mmol/L and 50 mg/L respectively, which was up 32.5 percentage points from static mode. The COD removal rate of wastewater was 42.8% after 120 min reduction and 120 min oxidation, but the COD removal rate was only 17.1% after the direct 120 min oxidation.