【作者】 班福忱；

【导师】 刘炯天；

【作者基本信息】 东北大学 ， 矿物资源利用与环境控制， 2010， 博士

【摘要】 三维电极-Fenton试剂法是在三维电极法和电Fenton法的基础上提出来的,是一种新型的电化学水处理技术,在环境污染治理领域的应用已初见端倪,深入开展有关研究具有重要的理论和现实意义。本文针对苯酚模拟废水为处理对象,以自制电化学反应器为试验装置,采用三维电极-Fenton试剂法对其进行了处理,主要内容如下：研究了铁板、石墨、Ti/RuO2-IrO2三种阳极材料、多孔石墨、活性炭纤维和不锈钢三种阴极材料对苯酚废水处理效果的影响,表明以Ti/RuO2-IrO2电极作为阳极,活性炭纤维作为阴极的电解体系苯酚去除率最高。研究了不同填料作为粒子电极对苯酚的去除率的影响,表明粒炭不适合做粒子电极,石英砂和活性炭混合比单一活性炭填料处理效果好；按比例投加涂膜活性炭和未涂膜活性炭能明显改善反应性能,提高苯酚去除率,涂膜活性炭与未涂膜活性炭体积比为1：2时苯酚去除率为95.9%。研究了清水条件下三维电-Fenton法产生H2O2的主要影响因素。在反应温度为20℃、反应时间为60min、pH值为3、电流密度为10mA/cm2、选用通入空气进行曝气等试验条件下,H2O2的产量为248.6mg/L,为下一步Fe2+投加奠定了理论与试验基础。研究了Na2SO4电解质投加浓度、苯酚水样浓度、pH值、反应时间、电解电压、Fez+投加浓度、极板间距、曝气强度等因素对三维电极-Fenton试剂法处理苯酚废水的影响,并对其影响作用机理进行了分析；在单因素试验基础上进行了正交试验,结果显示影响水样中苯酚去除率的因素主次顺序为pH值>电解电压>Fe2+投加浓度>极板间距>电解质投加浓度。根据正交试验结果,确定了最佳反应条件,在此条件下苯酚甲均去除率可达97.27%。研究了几种无机阴阳离子对反应体系的作用,得出Fe3+对该反应的作用取决于其在溶液中的浓度,适当浓度的Fe3+能够与Fe2+协同作用,促进增强Fenton试剂的催化氧化能力,而当Fe3+浓度过高时,反而起到抑制作用。CO32-、H2PO4-和Cl-对体系的催化氧化性能有不同程度的抑制作用,其抑制能力的大小为：CO32->H2PO4->Cl-。这些离子对反应体系的影响主要是对自由基的清除反应、或是参与了对铁离子的络合、对H202的无效分解等；N03-的存在对去除苯酚废水的催化氧化性能无明显影响。研究了各主要单因素对两种电Fenton法影响的不同；得出三维电极-Fenton试剂法对pH值的要求略低于二维电Fenton法；可以处理较高浓度的苯酚废水；电解电压、电解时间、电解质投加量等因素均低于二维电Fenton法,三维电Fenton法对苯酚的去除率比二维电Fenton法高出近20%。建立了三维电Fenton反应器与二维电Fenton (?)乏应器的能耗比值模型：通过能耗模型得出,三维电Fenton法比二维电Fenton法更节省能耗,在实际工程应用中值得推广。建立了三维电极-Fenton试剂法氧化降解苯酚废水的动力学模型,得出该过程符合一级动力学模型,在一定反应条件下,影响该反应速率的因素从强到弱顺序为：电压、Fe2+投加量、极板间距、电解质投加量、曝气强度。总反应拟合方程为Ct=C0exp (-1.05×10-12 U1.7784D1.2289M0.9941Q0.9210F1.4613t)。对苯酚降解机理进行分析,得出苯酚的去除主要是羟基自由基、电极的直接氧化以及体系中其它活性物种的共同作用的结果,在该体系中·OH的存在对苯酚降解贡献最大。通过对苯酚水样紫外-可见吸收光谱和气相色谱-质谱联机分析,得出苯酚氧化降解主要中间产物有苯二酚、醌类以及羧酸等。降解历程可能为：苯酚先被·OH氧化为芳环类苯二酚和醌类,随后开环氧化为羧酸类化合物,直至最后矿化为CO2和H20。更多还原

【Abstract】 Three-dimensional electrode-Fenton reagent method was put forward basing on the three-dimensional electrode method and electro-Fenton method.Aa a new type of electrochemistry water treatment technologies, it has begun to take shape in the field of environmental pollution control applications.So it has the important theoretical and practical significance to in-depth study about this mothod.In this paper,a self-made electrochemistry reactor was used to treat phenol simulation wastewater,using three-dimensional electrode-Fenton reagent method to treat it,mainly content as follows:The paper studies the influence of the three kinds of anode materials which are iron,graphite and Ti/RuO2-IrO2 and the three kinds of cathode materials which are porous graphite, activated carbon fiber and stainless steel on the effect of phenol wastewater treatment.. The results showed that the removal rate of phenol reached the tiptop in electrolysis system When using the Ti/RuO2-IrO2 as anode and the activated carbon fiber as cathode. At the same time,the paper studies the influence of the different paddings as particle electrode on the removal rate of phenol.The results showed that granule carbon was not suitable as particle electrode,and it had better treatment effect using quartz sand and active carbon as mixed padding than using single active carbon padding.It could improve the reactivity worth and enhance the removal rate of phenol obviously if proportional dosing of the active carbon doped membrane and the active carbon non-doped membrane.The removal rate of phenol was 95.9% when the volume ratio of active carbon doped membrane and active carbon non-doped membrane was 1:2.The paper studies the main factors of producing of the H2O2 by three-dimensional electric-Fenton method under the conditions of rinsing.The yield of H2O2 was 248.6mg/L in the reaction temperature was 20℃,the reaction time was 60min,the pH value was 3,the current density was 10mA/cm2,using pass into the air for aeration and other experiment contions.It establishes theory and experiment foundation for the dosing of Fe2+ for the next step.The paper studies the influence of the dosage concentration of Na2SO4 electrolyte,the sample concentration of phenol,the pH value,the reaction time, the electrolyte voltage, the dosage concentration of Fe2+, the pole distance and the aeration intensity on the effect of phenol wastewater treatment by three-dimensional electrode-Fenton reagent method,and analyses the mechanism of their effects. The orthogonal experiment was carried on basing on the single factor experiment. The results show that the primary and secondary sequence of influencing factor of phenol removal rate of the water sample was that pH value> electrolyte voltage> dosage concentration of Fe+2> pole distance> dosage concentration of electrolyte.According to the results of the orthogonal experiment to determine the optimal reaction conditions,the average removal rate of phenol is 97.27% under this condition.The paper studies the influence of several kinds of inorganic anion and cation on the effect of reaction system,and educes the effect of Fe3+ in the reaction depending on its concentration in solution.Appropriate concentration of Fe3+ has a synergetic effect with Fe2+,and promotes the ability of catalytic oxidation of Fenton reagent.But the high concentration of Fe3+ has a inhibitional effect.There is a different degrees of inhibitional effect of CO32-、H2PO4- and Cl-,and the capacity is CO32->H2PO4->Cl-.The effect of these ions on the reaction system is that the clear action of free radical,participating complexation of iron ion,or inefficacy decompose of H2O2. NO3-can hardly affect the ability of catalytic oxidation which to treatment phenol wastewater.The paper studies the different influences of the major single factor on the two kinds of E-Fenton methods,and educes the request of pH value of three-dimensional electrode-Fenton reagent method was lower than the two-dimensional,and it could be processed the high concentration of phenol wastewater.The reaction voltage,the electrolyte time and the addition quantity of electrolyte and other factors were all under the twe-dimensional E-Fenton method.The removal rate of phenol by three-dimensional E-Fenton method was higher than the two-dimensional E-Fenton nearly 20%.The paper establishes the energy consumption ratio model of three-dimensional E-Fenton reactor and two-dimensional E-Fenton reactor: Through the energy consumption model,we could educe that the three-dimensional E-Fenton method is more saving the energy than the two-dimensional E-Fenton method,and it is worth promoting in practical engineering applications.The paper establish a dynamic model of phenol wastewater oxidative degradation by three-dimensional electrode-Fenton reagent method and educes that it can be described with first order dynamic model.At a certain reaction conditions,the order of factors which affecting the reaction speed from strong to weak is voltage, the addition quantity of Fe2+, the pole distance, the addition quantity of electrolyte, the aeration speed.The fitting equation of overall reaction is Ct=C0exp (-1.05×10-12 U1.7784D1.2289M0.9941Q0.9210F1.46.3t) The degradation mechanism of phenol was analysed,and obtained that the removal of phenol is mainly result of joint action of hydroxyl radical,the direct oxidation of electrode and other active species in system.The hydroxyl radical in the system made the greatest contribution to the phenol degradation. Through the analysis of UV-VIS and GC-MS of phenol sample,the paper educes that the main intermediate product of phenol oxidative degradation are hydroquinone,quinones and carboxylic acid,etc.The degradation process could be that phenol was first oxidized to aromaticring hydroquinone and quinones by·OH,and then opened into a carboxylic acid compounds,until the last mineralized to carbon dioxide and water.更多还原