多孔陶粒负载纳米零价铁处理含磷废水的研究

Research on the Treatment of Phosphorus Containing Wastewater by Porous Ceramic Supported nZVI

摘要: 利用多孔陶粒作为载体，纳米零价铁为改性剂合成复合材料。以含磷废水为目标吸附物，研究多孔陶粒负载纳米零价铁对磷的去除性能。通过静态吸附实验，发现伪二级动力学方程能更好地描述多孔陶粒负载纳米铁对溶液中磷的吸附过程。柱实验的动态吸附试验，考察了柱高(填充率)、初始溶液的浓度、溶液的pH对吸附性能的影响。实验结果表明：当pH和初始浓度不变的条件下，柱高13 cm (填充率为65%)时，反应90 min时去除率最优，磷的去除率为86.74%。当柱高(填充率)和pH不变的条件下，初始浓度为10 mg/L，反应65 min时，磷的去除率94.21%。当柱高(填充率)和初始浓度不变的条件下，pH为4左右的去除率最高为95.7%。对各阶段的陶粒进行了X射线分析(XRD)，扫描电镜分析(SEM)和能量色谱分析(EDS)，结果表明，两种陶粒吸附除磷过程均主要为水溶液中的磷酸盐与吸附材料中含Si、Fe的有效组分发生配位体交换，同时也包含物理吸附和化学沉淀作用。

Abstract: The compound materials (nZVI@ PC) were prepared by using porousceramsite (PC) as a carrier and nano zero valent iron (nZVI) as modifier. The phosphorus removal efficiency of porous ceramic supported nZVI was studied, using waste water containing phosphorus as the target adsorbate. Through the static adsorption experiment, it was found that the pseudo-second-order kinetic equation can better describe the adsorption process of phosphorus in the solution using nZVI@ PC. The effects of the column height (filling rate), concentration of initial solution, pH of solution were investigated on the dynamic adsorption test of cylindrical experiment. The results showed that the removal rate was the best, it was 86.74% when reaction time was 90 min, the column height (filling rate) was 13 cm at a constant pH and initial concentration. The phosphorus removal rate was 94.21% when reaction time was 65 min, the initial concentration was 10 mg∙L−1 at a constant column height (filling rate) and pH. The phosphorus removal rate was 95.7% (the highest value) when the pH was 4 roughly, the column height (filling rate) and the initial concentration in the same conditions. X-ray diffraction (XRD), Scanning electron microscope (SEM) and Energy dispersive spectrometer (EDS) were used to analyze for each stage of ceramsite, the consequence showed that the adsorption and dephosphorization of the two kinds of ceramsite (PC and nZVI@ PC) were mainly, phosphate in aqueous solutions and the active component of Si and Fe in the material underwent ligand exchange, also containing physical adsorption and chemical precipitation.