RuO_2-IrO_2-SnO_2/Ti电极电催化氧化降解苯酚废水

Electrocatalytic Oxidation Degradation of Phenol Wastewater with RuO_2-IrO_2-SnO_2/Ti Anode

针对火炸药废水中所含苯酚类污染物排放量大、难降解的问题,以RuO_2-IrO_2-SnO_2/Ti为阳极、Ti为阴极,氯化钠为电解质,采用电催化氧化法对模拟含苯酚火炸药废水进行了研究。考察了氯化钠浓度、电流密度、pH值、苯酚废水初始浓度对苯酚去除率等的影响。在苯酚去除率最佳的条件下研究了总有机碳(TOC)、化学需氧量(COD)去除率随时间的变化。采用高效液相色谱法推测了降解苯酚的中间产物及过程。结果表明,在氯化钠浓度为13 g·L^(-1),电流密度为30 mA·cm^(-2),pH值为5,苯酚废水初始浓度为500 mg·L^(-1)的条件下,反应60 min,苯酚去除率可达99.85%。在苯酚去除率最佳的条件下,反应100 min,TOC和COD的去除率分别可达53.55%、59.37%。该电极易于催化ClO^-、·OH等活性基团与苯环发生亲电加成反应生成芳香族化合物,并迅速将其氧化降解为脂肪族化合物及CO_2和H_2O。

Aming at the problems of large emissions and difficult degradation for pollutant of phenol series contained in wastewater of propellants and explosives, the electrocatalytic oxidation of simulated wastewater of propellants and explosives with phenol was studied using RuO2-IrO2-SnO2/Ti as anode and Ti as cathode,sodium chloride as elecctrolyte.The effects of sodium chloride concentration, current density, pH value and initial concentration of phenol wastewater on phenol removal efficiency were investigated. The change in total organic carbon（TOC） and chemical oxygen demand （COD） with time were studied under the conditions of the best removal efficiency of phenol. The intermediate products and process of degradation of phenol were speculated by high performance liquid chromatography. Results show that under the conditions of sodium chloride concentration as 13 g·L-1, current density as 30 mA·cm-2, pH value as 5, initial concentration of phenol wastewater as 500 mg·L-1, when the reaction time is 60 min, the phenol removal efficiency is up to 99.85%. Under the conditions of the best removal efficiency of phenol, when the reaction time is 100 min, the removal efficiency of TOC and COD are 53.55% and 59.37%, respectively.The electrode is easy to catalyze the electrophilic addition reaction of ClO-,·OH and other active groups with benzene ring to form aromatic compounds, which can be oxidized to aliphatic compounds CO2 and H2O