超声强化铁碳微电解-Fenton法降解硝基苯废水

摘要

针对铁碳微电解（Fe0/GAC）-Fenton 法降解硝基苯（NB）废水时难连续运行的问题，采用超声（US）强化铁碳微电解-Fenton 法降解硝基苯废水。考察了超声对铁碳微电解-Fenton 法连续运行效果的影响，研究表明：不更换铁碳填料时，Fe0/GAC-Fenton法连续处理4批硝基苯废水时，硝基苯去除率从69.54%降至31.66%，TOC去除率也从48.11%降至19.20%；而US/Fe0/GAC-Fenton法处理4批相同废水时，硝基苯去除率均近至100%，TOC去除率均稳定在60%以上。与单纯Fe0/GAC-Fenton相比，超声不仅整体上强化了Fe0/GAC-Fenton法降解硝基苯废水的效率，还实现了连续多次高效运行。研究了pH、H2O2投加量及投加次数对Fenton法降解US/Fe0/GAC出水的影响规律，得到适宜操作条件：H2O2总投加量为4 ml并分5次添加，US/Fe0/GAC的出水pH调为4，反应30 min，最终硝基苯去除率达到100%，TOC去除率可达75%。%Based on the problem of poorly continuous operation of the iron-carbon micro-electrolysis (Fe0/GAC)-Fenton method in nitrobenzene (NB) wastewater treatment, ultrasound (US) was used to strengthen Fe0/GAC-Fenton. The Effect of ultrasound on continuous running of Fe0/GAC-Fenton was studied. The results show that, when Fe0/GAC is not changed, the removal rate of NB for 4 batches of same NB wastewater treated by Fe0/GAC-Fenton drops from 69.54%to 31.66%, and TOC removal rate is down to 19.20%from 48.11%;whereas under US/Fe0/GAC-Fenton, 4 times of NB removal rates are close to 100%, and TOC removal rates are above 60%. Compared with Fe0/GAC-Fenton, ultrasound not only enhance the degradation efficiency of Fe0/GAC-Fenton in NB wastewater treatment, but also achieve a continuous and efficient operation. The effect of pH, dosage and adding time of H2O2 on degradation of effluent of US/Fe0/GAC by Fenton method were studied. The suitable operating parameters are H2O2 total dosage 4 ml, adding time=5, US/Fe0/GAC effluent pH=4. Under these conditions, after 30 min, the removal rate of NB reaches 100%, TOC removal rate reaches 75%.