铁炭微电解法处理DNT生产废水

Treatment of Dinitrotoluene Production Wastewater by Iron-carbon Micro-electrolysis Method

针对DNT生产废水毒性大和难生物降解的特点,采用铁炭微电解法对DNT生产废水进行处理。研究了初始pH值、铁和活性炭质量比、电解质浓度与反应时间对DNT生产废水中硝基化合物及COD去除率的影响。用扫描电镜研究了微电解实验前后铁炭表面的形貌变化。结果表明,在铸铁与活性炭组成的微电解体系中,pH值为1、铁与活性炭的质量比为1.5:1.0、电解质Na_2SO_4质量浓度为300mg/L、反应时间为90min的操作条件下,硝基化合物和COD去除率分别为82.16%和68.43%,BOD_5/CODc,由0.035提高到0.280。反应后的铁炭表面被絮状体及片状晶体覆盖,从而抑制了微电解反应的进行。

Based on the characteristics of high toxicity and hard biodegradation of dinitrotoluene（DNT） production wastewater, the DNT production wastewater was treated by an iron-carbon micro-electrolysis method. The effects of initial pH value, iron-carbon mass ratio, electrolyte concentration and reaction time on the removal rate of nitro compounds in dinitrotoluene production wastewater and COD were studied. The variations of iron and carbon surfaces morphologies before and after micro-electrolysis experiment were investigated by scanning electron microscopy. The results show that under the operating conditions of pH value 1, mass ratio of Fe and C 1.5 ： 1.0, electrolyte mass concentration of Na2 SO4 as 300 mg/L and reaction time 90 min in the micro electrolysis system composed of cast iron and activated carbon , the removal rates for nitro compounds and COD were 82.16% and 68.43 %, respectively and the BODs/CODcr is increased from 0. 035 to 0. 280. After the reaction, the surface of the iron and carbon was covered by flocs and flaky crystals and thereby the micro-eletrolysis reaction was inhibited.