超声-Fenton试剂耦合降解水中苯酚的研究

Degradation of Phenol in Aqueous Solution via Hybrid Ultrasound-Fenton Reagent Process

采用超声-Fenton试剂耦合法降解水中的苯酚.单因素考察了反应时间、超声功率、Fenton试剂中H2O2和Fe2+的浓度配比、初始pH值以及反应温度对苯酚降解率的影响;采用正交实验法,得到各因素影响显著性的先后顺序为:Fenton试剂中H2O2与Fe2+的浓度配比、超声功率、反应时间、初始pH值;优化了降解反应的工艺条件:常压、30℃时,在超声频率为40 kHz、超声功率为400 W、H2O2和Fe2+的浓度分别为60 mmol/L和1.2 mmol/L、反应时间为10 min、初始pH值为3的最佳条件下处理100 mg/L的苯酚溶液,其降解率可达99.5%.在最佳工艺条件下对超声-Fenton降解苯酚的动力学研究发现:反应符合表观一级反应动力学.研究表明:超声-Fenton试剂耦合法明显优于二者的简单叠加,能够显著地缩短反应时间,提高苯酚的降解率.

The degradation of phenol in aqueous solution by ultrasound-Fenton reagent progress was studied. The effect of treating factors including the ultrasound power, the proportion of H2O2 and Fe^2＋ in Fenton reagent, the pH value, and the reaction temperature was investigated by the single factor method. The conditions of the ultrasound-Fenton reaction and the remarkable sequence of those treating factors were optimized by orthogonal experiment. In the optimal conditions with the ultrasound power of 400 W, the molar ratio of H2O2 to Fe^2＋ of 50 ： 1, pH of 3, the reaction temperature of 30℃, and the treatment time of 10 min, the degradation rate of phenol in aqueous solution can reach up to 99.5%. The reaction kinetics was discussed in the optimal conditions. The results show that the degradation of phenol by ultrasound- Fenton was in conformity with pseudo-first order kinetics. In addition, using ultrasound to the Fenton system could improve the treatment efficiency and shorten the reaction time.