Ti/SnO2-RuO2-Sb电极电氧化处理五氯苯酚模拟废水研究

采用刷涂-热解法制备了Sb、Ru掺杂的Ti/SnO2电极。通过SEM、EDX、XRD和循环伏安扫描(CV)表征了电极表面形态、组成、结构和电化学性质,并通过正交试验考察了电催化氧化降解五氯苯酚的影响因素。结果表明,各因素对五氯苯酚转化率影响的大小顺序依次为:底物初始质量浓度、反应温度、反应时间、电流密度、初始溶液pH值。在底物质量浓度为50mg.L-1,反应温度50℃,反应时间180min,电流密度40mA.cm-2,溶液初始pH值为8的条件下五氯苯酚的转化率达到97.6%。

Electrochemical oxidation of simulated pentachlorophenol sewage on a Ti/SnO2 - RuO2 -Sb electrode

This paper is related to the degradation of pentachlorophenol(PCP) with the electrocatalytic oxidation method.PCP,as one of the persistent organic pollutants(POPs),is supposed to be resistant to bacterial activities.They said electrocatalytic oxidation method is generally thought of as an alternative to sewage treatment and widely used for its advantages of being environmentally compatible and potentially cost-effective plus its versatility in use.To promote our degradation efficiency,we have prepared a Sb-Ru doped SnO2 electrode supported on titanium by brushing thermal decomposition.Then,we have analyzed the micrograph on the electrode surface,the element composition and the electrode structure via scanning electronic microscopy(SEM),energy dispersive X-ray(EDX) and X-Ray diffraction(XRD),respectively.The SEM image of the electrode surface clearly shows that the electrode surface is rough with much porous channel on its surface.Such kinds of surface topography tend to be able to enact electrochemical reactions over the relatively high superficial areas.Energy dispersive X-ray analysis indicates that the composition of the electrode is much similar to that of the precursor liquid,whereas XRD pattern of the electrode shows there exist diffraction peaks of SnO2 and RuO2.In addition,we have also done detailed analysis of the electrochemical features of the electrode by means of cyclic voltammogram(CV) with and without pentachlorophenol solution.Moreover,we have done a series of orthogonal experiments with our own made electrodes to test such relevant factors,as the initial concentration of substrate,reaction temperature,reaction time,current density,the initial aqueous pH,the electro-catalytic oxidation of PCP,etc.,thus witnessing the influence order of the factors on PCP conversion,such as the initial concentration of PCP>reaction temperature>reaction time>current density>the initial aqueous pH.And,finally,we have worked out the optimized reaction conditions,which can be expressed as follows: PCP concentration is 50 mg·L-1;the reaction temperature is 50 ℃;the reaction time is 180 min;current density is 40 mA·cm-2;the pH value is 8.And,last of all,the PCP and the total organic carbon(TOC) conversion can be made to reach 97.6% and 30.1%,respectively.