EDTA改性高吸水树脂对铜离子的吸附研究

摘要

以丙烯酸(AA)为单体,EDTA二钠为改性添加剂,过硫酸铵(APS)/亚硫酸钠为氧化还原型引发剂,N,N′-亚甲基双丙烯酰胺(NMBA)为交联剂,采用水溶液聚合法合成EDTA改性高吸水树脂.发现使用改性添加剂EDTA二钠能够使改性高吸水树脂的吸附铜离子性能明显增强.通过正交实验和单因素实验进行条件优化,得出改性高吸水树脂对重金属铜离子吸附性能最佳的工艺条件为:以15 mL的丙烯酸为基准,反应温度为65℃,单体质量分数为23.08%,中和度为65%,改性添加剂质量为0.4 g,交联剂和引发剂质量分别为聚合单体质量的0.9%和1.5%.在最佳工艺条件下,制备的改性高吸水树脂常温下在0.1mol·L-1的硫酸铜溶液中吸附铜离子量达到225.18 mg·g-1.%The modified high water-absorbing resin was prepared by aqueous solution polymerization with acrylic acid(AA)as the monomer,disodium ethylene diamine tetraacetic acid (EDTA-Na2 )as the modified additives,N,N-methylene double acrylamide (NMBA)as cross-linking agent,ammonium per-sulfate(APS)/sodium sulfite as oxidation reduction type initiator. It was found that the adsorption performance of absorbent resin modified by EDTA-Na2 strengthened obviously. Orthogonal and single factor experi-ment were used to establish the optimum parameters related to the product preparation. The best process conditions on adsorption properties of the modified resin for heavy metal copper ions was obtained. Using 15 mL acrylic acid as a benchmark,the result showed the optimum process conditions:the reaction temperature was 65℃,the mass fraction of monomer was 23. 08%,the neutral-ization degree was 65%,modified additive dosage was 0. 4 g,the dosage of cross-linking agent was 0. 9%,and the initiator dosage was 1. 5%,respectively. After made under the optimum process conditions,the adsorption properties of modified resin for heavy met-al copper ions in the 0. 1mol·L-1 copper sulfate solution was 225. 18mg·g-1 at room temperature.