Fenton法降解1,5-萘二磺酸废水及作用机制研究

The influence factors and degradation mechanism of 15-naphthalenesulfonic acid wastewater with Fenton reagent

采用Fenton法降解1,5-萘二磺酸模拟废水,考察了H2O2和Fe^2+投加量、反应温度、溶液初始pH以及废水中常见无机阴阳离子等因素的影响,并借助紫外光谱、化学需氧量(COD)、5日生物需氧量(BOD5)、总有机碳(TOC)的检测结果以及叔丁醇的影响对反应机制进行了初步探讨.结果表明,1,5-萘二磺酸初始COD 900 mg/L时,控制反应温度25~35℃,溶液pH在3.0~5.0之间,H2O2和Fe^2+投加量分别为56.12 mmol/L和2.790 mmol/L时,反应30 min后,COD和TOC去除率分别达到79.8%和28.2%;SO4^2-、Cl^-、F-和H2PO4^-4种阴离子对1,5-萘二磺酸降解均具有抑制作用,而Fe^3+和Cu^2+起促进作用;叔丁醇对比实验表明,Fenton降解1,5-萘二磺酸主要是·OH的氧化作用,并最终降解为CO2和H2O;控制反应时间60 min,溶液的B/C值由降解前的小于0.1提高到0.35,废水生化性明显提高.

In the present work,the simulated wastewater of 1,5-naphthalenedisulfonic acid was treated with Fenton reagent.The effects that affected the removal efficiency of COD,such as the dosages of H2O2and Fe2+,reaction temperature,initial pH,and inorganic ions,were investigated in detail.The degradation mechanism was discussed by using ultraviolet spectroscopy,chemical oxygen demand and total organic carbon analysis,and the reaction with tert-butyl alcohol.The optimal conditions for the degradation of 1,5-naphthalenedisulfonic acid was found to be of 900 mg/L of the initial COD of 1,5-naphthalenedisulfonic acid,25-35℃of temperature,3.0-5.0 of p H,56.12 mmol/L of H2O2dosage,2.790 mmol/L of Fe2+dosage,and 30 min of reaction time.F-、Cl-、SO4^2-and H2PO4^-had inhibiting effects on the degradation of 1,5-naphthalenedisulfonic acid,while Fe3+and Cu2+exhibited positive effect.The significant inhibiting effect by tert-butyl alcohol suggested the oxidation mechanism of 1,5-naphthalenedisulfonic acid with Fenton reagent mainly via an approach of hydroxyl radical.The final products from degradation of 1,5-naphthalenedisulfonic acid were CO2and H2O.After 6 0 min of degradation reaction,the B/C ratio of simulated wastewater was increased from less than 0.1 to 0.35,which greatly improved the biodegradability of the wastewater.