Chen Quanzhou, Zhou Kanggen, Hu Yuanjuan, Liu Fang, Wang Aihe
Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China and Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China E-mail:
Water Sci Technol. 2017 Mar;75(5-6):1294-1308. doi: 10.2166/wst.2016.548.
In this paper, a poly ligand exchanger, Cu(II)-loaded chelating resin named ammonia adsorption reagent (AMAR), bearing the functional group of weak iminodiacetate acid, was prepared to efficiently remove ammonia from solutions. Batch adsorption equilibrium experiments were conducted under a range of conditions. The effects of pH on the removal of ammonia by AMAR were investigated at 25 °C. The copper loaded on the resin forms a complex with NH in solution under alkaline condition. The effect of alkaline dosage (AD) on the ammonia adsorption was investigated. The maximum breakthrough bed volumes were obtained when the AD was set as 0.75 mmol OH/mL. The higher AD did not guarantee the better ammonia removal efficiency due to the forming of Cu(OH) precipitate between OH in solutions and Cu(II) on the resin. The effect of competing ions on the adsorption breakthrough curve of virgin AMAR and causticized AMAR was also investigated. The results demonstrated that the existence of competing ions had a negative impact on the adsorption capacity for both virgin AMAR and causticized AMAR. After causticization, the AMAR was more resistant to the competing ions comparing with virgin AMAR. The bivalent Ca affects the ammonia adsorption more than does the monovalent Na.
本文制备了一种负载铜（II）的螯合树脂——氨吸附试剂（AMAR），它是一种多配体交换剂，带有弱亚氨基二乙酸官能团，用于从溶液中高效去除氨。在一系列条件下进行了间歇吸附平衡实验。在25℃下研究了pH对AMAR去除氨的影响。树脂上负载的铜在碱性条件下与溶液中的NH形成络合物。研究了碱用量（AD）对氨吸附的影响。当AD设定为0.75 mmol OH/mL时，获得了最大穿透床体积。由于溶液中的OH与树脂上的Cu（II）之间形成了Cu（OH）沉淀，较高的AD并不能保证更好的氨去除效率。还研究了竞争离子对原始AMAR和苛化AMAR吸附穿透曲线的影响。结果表明，竞争离子的存在对原始AMAR和苛化AMAR的吸附容量都有负面影响。苛化后，与原始AMAR相比，AMAR对竞争离子的耐受性更强。二价Ca对氨吸附的影响比一价Na更大。
