Study on Methods for Removal and Concentration of Metal Ions Solved in Water Using Macro-Molecules

1.制备了水溶性螯合聚合物聚(α-乙酰氨基丙烯酸)(简称P4A)和聚(N-甲基丙烯酰基-L-丙氨酸)(简称：PMLA)。P4A和PMLA的重均分子量分别为1100000和2200000。在pH为4~6的范围内，用间歇超滤法测定了P4A和PMLA与二价金属离子(Co(II)、Ni(II)、Cu(II)、Zn(II)、Pb(II))的结合平衡。结果表明，络合模型能较好地描述结合平衡曲线。通过对模型计算的结合曲线与实验曲线的拟合，确定了各溶液的平衡稳定常数和连续稳定常数。含2-乙基己基-2-乙基己基的微胶囊。以二乙烯基苯为原料，采用水-油-水乳液原位聚合法制备膦酸酯(PC88A)。所制备的微囊几乎都是球形的，直径为200~300μm(扫描电子显微镜观察)。在pH为1~4的范围内测定了稀土金属离子的吸附平衡。结果表明，即使在pH 2~3的酸性溶液中，该微胶囊也能吸附稀土金属离子。从这些结果来看，微胶囊似乎对回收或浓缩溶解在水中的金属离子是有用的。用磷酸钙、磷酸氢钙和磷酸二氢钙对水中溶解的金属离子进行了固定化研究。三种磷酸盐对铅离子的去除效果较好，但仅磷酸氢钙对钴(II)、铜(II)和镉(II)的去除效果较好。基于溶解-沉淀机理，讨论了磷酸盐对金属离子的固定作用。

1. Water-soluble chelating polymers, poly(α-acethylaminoacrylic acid) (abbreviation : P4A) and poly(N-methacryloyl-L-alanine) (abbreviation : PMLA) were prepared. The weight average molecular weight of P4A and PMLA were 1100000 and 2200000, respectively. Binding equilibria of P4A and PMLA with divalent metal ions (Co(II), Ni(II), Cu(II), Zn(II), Pb(II)) were measured by a batch ultrafiltration method in the pH range 4-6. It was shown that the binding equilibrium curves were reasonably well represented by the complexation model proposed previously. The equilibrium and successive stability constants were determined by fitting the binding curves calculated from the model to the experimental ones at every solution pH.2. Microcapsules .containing 2-ethylhexyl 2-ethylhexyl. Phosphonate(PC88A) were prepared by an insitu polymerization of divinyl benzene with water-oil-water emulsion. Almost all the microcapsules prepared were spherical with diameters of 200-300 μm (SEM observation). Adsorption equilibria of rare earth metal ions were measured in the pH range 1-4. It was shown that the microcapsules adsorbed rare earth metal ions even in acidic solution of pH 2-3. From these results, the microcapsules seem to be useful to recover or concentration metal ions dissolved in water.3. Immobilization of metal ions dissolved in water was examined with calcium phosphate, calcium hydrogen phosphate and calcium dihydrogen phosphate. Lead ions were favorably removed with these three kinds of phosphates, but Co(II), Cu(II) and Cd(II) were removed with only calcium hydrogen phosphate. The immobilization of metal ions with phosphates was discussed based on a dissolution-precipitation mechanism.