层状双羟基复合金属氧化物去除水中磷酸根的研究

发布时间：2018-06-24 23:10

  本文选题：水滑石 + 吸附　； 参考：《东北石油大学》2017年硕士论文

【摘要】：由于富含磷等营养物质废水的持续排放,造成水体富营养化,水体中藻类大量疯长,溶氧量下降,水质恶化,严重破坏生态坏境。磷进入水环境的主要途径是含磷工业废水,生活污水的排放,因此,在污、废水排放前有效地去除磷,是控制水体富营养化的重要手段。吸附法由于具有操作简单、高效低耗、低污染和可循环等优点,已成为国内外除磷研究的热点之一。水滑石是典型的阴离子吸附剂在处理废水中阴离子方面具有独特优势。本文采用水热法和共沉淀法制备不同类水滑石,通过X射线衍射(XRD)、扫描电镜(SEM)和能谱(EDS)、傅里叶变换红外光谱仪(FTIR)、比表面积及孔隙率分析仪(BET)及电位分析仪(Zeta)等手段对吸附剂进行表征分析及吸附机理的研究,并应用于模拟水溶液中的磷吸附,实验主要内容包括:一、本文采用工艺简单且廉价的水热法改变层间二价阳离子,制备四种不同类型二元X/Al-LDHs(X为Mg、Zn、Ni、Co)样品。研究表明:在25℃下,初始pH=6的条件下,Zn/Al-LDHs吸附效果最好,对磷酸根的去除率达92%,吸附量是24.965 mg/g,其磷吸附均符合准二级动力学模型和Langmuir模型,吸附热力学研究表明四种类水滑石吸附磷是吸热且自发过程,吸附剂循环使用3次,去除率在60%以上。二、近一步重点研究不同三价阳离子的Ni/Co二元类水滑石,水热法合成Ni/Co-C-LDHs,将类水滑石层间阴离子换层,共沉淀法制备Ni/Co-N-LDHs。通过对吸附剂结构的表征和吸附性能的评价,研究吸附机理。Ni/Co-N-LDHs比表面积为288.2683m2/g,利于吸附反应。实验结果表明,在25℃、pH=6条件下,去除率升高到98%,最大吸附容量为49.78 mgP/g。吸附动力学满足准二级动力学模型,证明主要是化学吸附过程。吸附等温线符合Langmuir模型,说明吸附过程为单层吸附。热力学研究表明磷吸附实验是吸热且自发的,吸附机理主要是离子交换,同时包括表面吸附等过程,Ni/Co-N-LDHs循环使用3次,去除率仍在75%以上,有较好的再生性及稳定性。
[Abstract]:Due to the continuous discharge of phosphorus rich nutrient wastewater, the eutrophication of water body is caused, the algae in the water body grows wildly, the dissolved oxygen quantity decreases, the water quality deteriorates, and the ecological environment is seriously damaged. The main way for phosphorus to enter the water environment is the discharge of industrial wastewater containing phosphorus and domestic sewage. Therefore, it is an important means to control eutrophication of water body to remove phosphorus effectively before sewage and wastewater discharge. Because of its advantages of simple operation, high efficiency and low consumption, low pollution and recyclability, adsorption method has become one of the hot spots in phosphorus removal at home and abroad. Hydrotalcite is a typical anionic adsorbent with unique advantages in the treatment of anions in wastewater. In this paper, different hydrotalcite-like materials were prepared by hydrothermal method and co-precipitation method. The adsorbent was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy spectrum (EDS), Fourier transform infrared spectroscopy (FTIR), specific surface area and porosity analyzer (BET) and potential analyzer (Zeta). The main contents of the experiments are as follows: firstly, four kinds of binary X / Al-LDHs (X is MgZnZn-NiNiHs) samples were prepared by changing interlayer divalent cations by simple and cheap hydrothermal method. The results showed that the adsorption efficiency of Zn- / Al-LDHs was the best at 25 鈩，

本文编号：2063401