【作者】 缪虹；

【导师】 孙亚兵；

【作者基本信息】 南京大学 ， 环境工程， 2012， 硕士

【摘要】 难降解有机物具有一定的生物抑制性,难以生化降解。采用电化学方法研究对硝基酚废水、焦化废水处理工艺,通过研究发现电化学法处理难降解有机废水具有一定的可行性。电极材料是电化学技术的核心内容之一,主要考虑的因素有电催化活性、稳定性、导电性等。本论文采用电沉积法制备不同掺杂电极,研究发现与制备的其他电极相比,Fe掺杂PTFE-PbO2/TiO2-NTs/Ti电极析氧电位、寿命、电催化活性都有较大提高。实验中分别改变电流密度、初始浓度、pH、电解质、降解时间等影响因素,以对硝基酚和CODcr浓度为指标,确定Fe掺杂PTFE-PbO2/TiO2-NTs/Ti电极降解对硝基酚废水的最佳反应条件。研究结果表明·OH的产生随着电流密度的增大而增大,因去除率也随着电流密度增大而增大；初始浓度大,扩散增强,但产生的中间产物参与·OH竞争,降解效果不如初始浓度小的好；pH在酸性条件下能抑制析氧反应；当电解质为NaCl时,C1-被氧化为具有去强氧化性的C10",去除效果加强。电解质为Na2S04时,在一定的浓度范围内浓度越高,产生具有氧化性的S2O82-加强氧化。实验最佳的影响因素为电流密度20mA/cm2,初始浓度100mg/L,pH5.1,Na2S04浓度0.02mol/L其次以焦化废水为研究对象,与上述模拟废水对比,研究Fe掺杂PTFE-PbO2/TiO2-NTs/Ti对实际废水降解的效果。改变电流密度、pH和电解时间等影响参数发现,电流密度越大,CODc,和NH3-N去除效率越高,同时也发现,在同一条件下氨氮的去除率高于CODcr,NH3-N优先降解；pH酸性时CODc,去除效果比较好,pH碱性时NH3溢出,NH3-N的去除效率较好。焦化废水在电流密度20mA/cm2,pH7,降解30min时即可达标排放。更多还原

【Abstract】 The refractory organics owns biologic inhibitory and are difficult to biochemical degradation.Nitrophenol wastewater, cooking wastewater treatment process were studied in this paper.The research has found that the electrochemical treatment of refractory organic wasterwater is feasible.Electrode material is one of the cores of the electrochemical techniques and the main considerations are the electro-catalytic activity, stability, conductivity, etc. Different anodes were prepared by anodic electrodeposition technique. We found that compared to other anodes, Fe doped PTFE-PbO2/TiO2-NTs/Ti shows better properties such as oxygen evolution potential, service life, electro-catalytic activity.Using p-NP and CODcr concentration as an indicator and changing the different values of experimental paramenters about current density, initial concentration, pH supporting electrolyte and degradation time, we were mainly to find out the optium reaction conditions on p-NP degradation over Fe doped PTFE-PbO2/TiO2-NTs/Ti electrode. The generation of·OH increases with the current density, so the removal rate increases with the increase of current density; the larger the initial concentration, the stronger the diffusion. But the intermediates involved in the competition of·OH degradation, so the effect was not so good as the lower initial concentration.It can inhibit the oxygen evolution reaction under the acidic condition. When the electrolyte was NaCl, Cl-was oxided to the strong oxidizing ClO-which can improve the removal effiency; choosing Na2SO4as the electrolyte, in a certain concentration, the higher the concentration of Na2SO4, the more oxidizing S2O82-, which can also strengthen the degradation. Therefore the optimum experimental parameters for the current density was20mA/cm2, the initial concentration was100mg/L, pH was5.1, the concentration of Na2SO4was0.02mol/L.Then compared with the above simulated wastewater and making the coking wasterwater as the research object, we were mainly to research the Fe doped PTFE-PbO2/TiO2-NTs/Ti electrode on the actual wasterwater degradation.Changing the experimental parameters of the current density, pH and electrolysis time, we found that the higher the current density, the higher CODcr and NH3-N removal rate and the NH3-N removal efficiency was better than CODcr in the same condition. CODcr removal efficiency was higher in the acidic solution, and NH3removal efficiency was higher in the alkaline solution for NH3can overflow from the solution.In the current density20mA/cm2, pH value7, coking wastewater could be charged after30min degradation.更多还原