大孔丙烯酸系离子交换树脂对硝酸根离子吸附性能的研究

发布时间：2018-03-06 03:23

  本文选题：丙烯酸系阴离子交换树脂　切入点：烷基化　出处：《东南大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着城镇污水处理厂污染物排放标准的全面提标,污水厂对总氮的排放开始受到严格控制。受传统生物法脱氮效率的限制,很多污水处理厂总氮排放难以达标,而硝态氮浓度偏高是其主要原因。硝酸盐对人体具有致癌、致畸、致突变性,水体环境中过量的硝酸盐会导致水体富营养化。离子交换法因其工艺简单,效果稳定,可重复使用等特点,被视为对硝酸根离子污染水最有效的处理方法之一。相比于目前常用的聚苯乙烯系阴离子交换树脂,丙烯酸系离子交换树脂抗有机污染能力更强,更适用于地表水环境中。为寻求吸附容量大、选择性好、再生效率高、抗有机污染能力强的离子交换树脂,本文通过对丙烯酸系弱碱性阴离子交换树脂D311进行烷基化反应制备两种强碱性阴离子交换树脂D31]-C2及D311-C3,并以丙烯酸系强碱性阴离子交换树脂D213和聚苯乙烯系硝酸盐专用树脂Purolite A 520E作对比,研究了树脂对N03-的吸附-脱附性能,并研究了其抗有机污染能力,主要内容如下：(1)树脂制备：将溴乙烷及溴代正丙烷与弱碱性阴离子交换树脂D311进行烷基化反应,制备树脂D311-C2及D311-C3,测定了其交换容量,研究表明强碱交换容量均达到3.4mmol/g以上,强碱交换容量明显提高。(2)树脂的吸附性能：研究了D311、D311-C2、D311-C3及D213四种树脂的吸附性能,结果表明：四种树脂对N03-的吸附等温线均符合Langmuir模型,25℃条件下D311、D311-C2、D311-C3及D213四种树脂饱和吸附量分别为：17.24、40.82、40.32、41.15mg/g；树脂的吸附动力学曲线可用准二级动力学方程描述；树脂对N03-的吸附是自发进行的放热过程；溶液pH值的变化对强碱性阴离子交换树脂D311-C2、D311-C3及D213吸附容量的影响很小；在氯离子及硫酸根离子存在条件下,D311-C3的选择性最好；0.8M的氯化钠溶液为树脂的最佳脱附剂,脱附率达到95%以上。(3)树脂抗有机污染能力：研究了D311-C2、D311-C3、D213及Purolite A 520E四种树脂的抗有机污染性能,结果表明：丙烯酸系阴离子交换树脂再生效率高,抗有机污染能力明显强于聚苯乙烯系交换树脂。树脂应用研究表明：D311-C2及D311-C3均可以很好的应用于污水厂二级出水硝态氮的深度处理,具有较好的应用前景。
[Abstract]:With the comprehensive standard of pollutant discharge in urban sewage treatment plant, the discharge of total nitrogen in sewage treatment plant is strictly controlled. Due to the limitation of traditional biological nitrogen removal efficiency, many sewage treatment plants have difficulty in meeting the standard of total nitrogen discharge. The high concentration of nitrate is the main reason. Nitrate is carcinogenic, teratogenic, mutagenicity, excessive nitrate in the water environment will lead to eutrophication. It is regarded as one of the most effective treatment methods for nitrate ion polluted water. Compared with the common polystyrene anion exchange resin, acrylic ion exchange resin has stronger resistance to organic pollution. It is more suitable for surface water environment. In order to seek ion exchange resin with large adsorption capacity, good selectivity, high regeneration efficiency and strong resistance to organic pollution, In this paper, two strong basic anion exchange resins D31] -C2 and D311-C3 were prepared by alkylation of acrylic weak basic anion exchange resin D311. The special resin Purolite A520E was compared, The adsorption-desorption property of N03- was studied, and its ability to resist organic pollution was studied. The main contents were as follows: the alkylation of bromoethane and bromo-n-propane with weak basic anion exchange resin D311 was studied. Resin D311-C2 and D311-C3 were prepared. The exchange capacity of D311-C2 and D311-C3 was determined. The results showed that the exchange capacity of strong alkali was over 3.4 mmol / g, and the adsorption capacity of D311C _ 311-C _ 2C _ 311-C _ 311-C _ 3 and D _ 213 were studied. The results show that the adsorption isotherms of four resins for N03- are in accordance with the Langmuir model at 25 鈩，

本文编号：1573137