基于离子色谱法测定水环境中氨氮及含磷化合物的研究

发布时间：2018-01-16 12:09

本文关键词：基于离子色谱法测定水环境中氨氮及含磷化合物的研究　出处：《浙江大学》2017年硕士论文　论文类型：学位论文

【摘要】：水域的富营养化是普遍的水环境问题之一。氮磷化合物则是富营养化的重要因素。氮磷化合物在水质中以各种形态存在,也蓄积在水域沉积物中,不时释放,因此监测水质及沉积物中氮磷化合物,具有一定的环保监测意义。离子色谱(IC)是分析各种离子化合物的有效手段之一,其自动化程度高、操作简便,被广泛应用于环境、食品、能源及医药化工等众多领域。本文利用双系统离子色谱法同时测定了水中氨氮及过硫酸盐的含量,并对过硫酸盐的降解作用做了初步研究。采用加速溶剂萃取技术,提取沉积物中无机正磷酸盐及多聚磷酸盐,运用离子色谱法进行测定。主要研究由以下三章构成。第一章:介绍了氮磷化合物的有关概况,并对氨氮、过硫酸盐、无机正磷酸盐、多聚磷酸盐的有关检测方法进行了综述。第二章:建立了一种测定湖水中氨氮和过硫酸根的双系统离子色谱法。在加热条件下过硫酸根分解水体中的氨氮,通过双系统离子色谱,它们分别以甲烷磺酸和氢氧化钾为淋洗液,抑制电导检测。该方法实现了同时检测湖水中阳离子(氨氮)和阴离子(过硫酸盐)。第三章:采集富营养化水域环境中的土壤和沉积物,对快速溶剂萃取条件进行优化,处理及提取样品后过微孔滤膜和预柱直接进行离子色谱分析。按照从简到繁,从等度淋洗到梯度淋洗的顺序依次摸索,研究了含磷化合物的离子色谱条件。1:选用IonPac AS23为阴离子分析柱,以Na2CO3-NaHCO3-NaOH溶液体系等度淋洗,测定了磷酸盐和亚磷酸盐。2:IonPacAS11为阴离子分析柱,氢氧化钾溶液梯度淋洗,同时测定焦磷酸盐及其它常规阴离子。3:以IonPacAS19高容量阴离子交换分析柱进行分离,淋洗液自动发生装置在线产生KOH进行梯度洗脱,抑制型电导检测,40min内同时测定湖底沉积物中三聚磷酸盐及常规阴离子和部分含磷化合物(亚磷酸盐、磷酸盐、焦磷酸盐、三偏磷酸盐)。通过分离度、精密度、准确度等指标判断,认为IonPacAS19为分析柱,氢氧化钾梯度淋洗的色谱条件下,能有效的分离测定各种含磷化合物和常规阴离子,该法为最优的离子色谱法,操作简便,完全适合开展各种含磷化合物(亚磷酸盐、磷酸盐、焦磷酸盐、三聚磷酸盐)和常规阴离子的分离测定。
[Abstract]:Eutrophication in water is one of the most common problems in water environment. Nitrogen and phosphorus compounds are important factors of eutrophication. Nitrogen and phosphorus compounds exist in various forms in water quality, and they are also accumulated in water sediments and released from time to time. Therefore, the monitoring of nitrogen and phosphorus compounds in water quality and sediment has a certain environmental monitoring significance. Ion chromatography (IC) is one of the effective means for the analysis of various kinds of ionic compounds, its automation is high, and the operation is simple. It has been widely used in many fields such as environment, food, energy, medicine and chemical industry. In this paper, the content of ammonia nitrogen and persulfate in water was determined by double system ion chromatography. The degradation of persulfate was studied. Inorganic orthophosphate and polyphosphate were extracted from sediments by accelerated solvent extraction. The determination was carried out by ion chromatography. The main research was composed of the following three chapters. Chapter 1: the introduction of nitrogen and phosphorus compounds, and the ammonia nitrogen, persulfate, inorganic orthophosphate. In chapter 2, a dual-system ion chromatography method for the determination of ammonia-nitrogen and persulfate in lake water was established. Under the condition of heating, the ammonia-nitrogen in water was decomposed by persulfate radical. By dual system ion chromatography, methanesulfonic acid and potassium hydroxide were used as eluent respectively. Inhibition conductance detection. This method can simultaneously detect cations (ammonia nitrogen) and anions (persulfate) in lake water. Chapter 3: collecting soil and sediment in eutrophic water environment. The conditions of rapid solvent extraction were optimized, the samples were treated and extracted, the microporous filter membrane and the pre-column were directly analyzed by ion chromatography, and the sequence of isotropic elution to gradient elution was studied from simple to complex. The ion chromatographic conditions of phosphate compounds were studied. 1. IonPac AS23 was selected as anion analysis column and isoprene elution was carried out in Na2CO3-NaHCO3-NaOH solution system. The determination of phosphate and phosphite. 2: Ion PacAS11 was carried out on anion analytical column with gradient elution of potassium hydroxide solution. Simultaneous determination of pyrophosphate and other conventional anions. The separation was carried out on a IonPacAS19 high capacity anion exchange analytical column, and the KOH was generated on line by an automatic eluant generator for gradient elution. The inhibitory conductance test was used to simultaneously determine tripolyphosphate, conventional anions and some phosphate compounds (phosphite, phosphate, pyrophosphate) in lake bottom sediments within 40 minutes. Based on the determination of separation degree, precision and accuracy, it is considered that IonPacAS19 is an analytical column with gradient elution of potassium hydroxide. This method is the best ion chromatography method, which is simple and suitable for the development of various phosphate compounds (phosphite, phosphate, pyrophosphate). Separation and determination of tripolyphosphate and conventional anions.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X832;O657.7

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