采用微波促进Fe2+-K2S2O8体系处理甲基橙(MO)染料废水,考察了初始pH、微波功率、反应时间、K2S2O8投量及K2S2O8与Fe2+摩尔比对MO脱色率的影响,同时对不同处理方式进行了比较,并进行了降解机理探讨和动力学分析。结果表明,微波促进Fe2+-K2S2O8体系能快速降解废水中的MO,在50 mL初始pH=6、质量浓度为500 mg/L的MO废水中,微波功率280 W,微波辐照9 min,c(K2S2O8)为9.82 mmol/L,K2S2O8与Fe2+摩尔比为50的优化处理条件下,MO脱色率达到了98.6%,微波促进Fe2+-K2S2O82-体系降解MO废水产生了协同效应。动力学研究表明,反应符合1级反应动力学规律,反应速率常数k=0.341 4 min-1,反应半衰期2.03 min。
An advanced oxidation process of microwave enhanced Fe2+-K2S2O8system has been used for degradation of methyl orange(MO) wastewater.The effects of initial pH,microwave power,radiation time,K2S2O8dosage and Fe2+-K2S2O8molar ratio on MO decolorization rate are investigated,and different treatments on degradation efficiencies are compared.The possible degradation reaction mechanism and kinetics analysis are discussed.The results show that the methyl orange(MO) wastewater was degraded rapidly in the system of Fe2+-K2S2O8coupled with microwave radiation and the decoloration rate of the MO was up to 98.6% under the best conditions,i.e.,pH = 6,V=50 mL,ρ(MO)=500 mg/L,microwave input power=280 W,irradiation time=9 min,c(K2S2O8)=9.82 mmol/L,n(K2S2O8)/n(Fe2+)=50.Catalytic degradation for MO in microwave enhanced Fe2+-K2S2O8system have synergetic effect.Kinetics study indicated that the treatment process accorded with the first order reaction kinetic,the reaction velocity constant k is 0.341 4 min-1,and the half life t1/2is 2.03 min.