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优选亚氨基二乙酸螯合树脂D463,系统考察了其对废水中镍-氨络合离子的吸附性能与机理。研究表明,镍离子吸附量随氨浓度升高而先升高后降低;采用Langmuir等温方程获得的镍离子最大吸附量为2.206mmol/g;氨与镍离子分别在120min和500min左右达到吸附平衡,准一级动力学方程和准二级动力学方程均可对镍离子的动力学曲线进行较好的模拟,氨和镍离子吸附量比随时间的进行先增大后减小。结合液相形态以及固相FT-IR和XPS分析,推测镍-氨双组份的吸附过程存在竞争与促进的交互作用:碱性体系中氨与镍离子形成阳离子络合物,促进镍离子的吸附,过量氨与镍离子竞争相同的树脂吸附位点,表现为相互抑制作用,但游离镍离子与树脂的螯合作用更具优势。该树脂对重金属的吸附回收具有广谱性。镍-氨和铜-氨体系动态吸附曲线表明镍离子和铜离子的穿透点分别为260BV和520BV,且1BV 12%硫酸和1BV的水可彻底再生D463,证明D463在含高氨废水中分离回收重金属离子方面具有广阔的应用前景。
Iminodiacetic acid chelating resin D463 is preferred, and its adsorption performance and mechanism on nickel - ammonia complex ion in wastewater are systematically investigated. The results show that the adsorption capacity of nickel increases firstly and then decreases with the increase of ammonia concentration. The maximum adsorption capacity of nickel ion obtained by Langmuir isotherm is 2.206mmol / g. The adsorption equilibrium of ammonia and nickel ion reaches about 120min and 500min respectively, Quasi-first-order kinetic equation and quasi-second-order kinetic equation can simulate the kinetic curves of nickel ions. The adsorption capacity of ammonia and nickel increases first and then decreases with time. Combining with the liquid phase morphology and the FT-IR and XPS analysis, it is speculated that there exists competition and promotion interaction between the nickel-ammonia two component adsorption process: ammonia and nickel ions form alkaline-earth complex in alkaline system, Adsorption, excess ammonia and nickel ions compete for the same resin adsorption site, showing a mutual inhibitory effect, but the free nickel ions and resin chelation more advantage. The resin has a broad spectrum of adsorption and recovery of heavy metals. The dynamic adsorption curves of nickel-ammonia and copper-ammonia system show that the penetration points of nickel ion and copper ion are 260BV and 520BV, respectively, and 1BV 12% sulfuric acid and 1BV water can completely regenerate D463, which proves that D463 is separated in wastewater containing high ammonia Recovery of heavy metal ions has broad application prospects.