Acrylic three-dimensional networks. II. Behavior of different acrylic ion exchangers in the retention and elution processes of some metal cations

摘要

The retention process of the Cu(II) and Ni(II) cations from CuSO4 and NiSO4 aqueous solutions by eight acrylic ion exchangers was studied. Also, the elution process of these cations with 0.5 mol · L-1 HCl solution was analyzed. The quantitative retention and elution as well as the development aspects of the two processes were observed by the column method. Seven ion exchangers contained weak base, weak acid, and amphoteric functional groups, these being known as chelating agents. Also, an ion exchanger with carboxylic groups, as a model, was taken in this study. The experiments show that the ion exchangers can be divided in three types as follows: (a) bad chelating agents; (b) chelating ion exchangers with the limited efficiency; (c) ion exchangers with good chelating properties and a high application efficiency; especially, the ion exchanger with hydroxamic functional groups is considered in this class. Also, the experimental data prove that, both for Cu(II) and Ni(II) cations, the volume of the purified effluent is higher than the HCl volume needs for their complete elution. This fact means concentration of the metal cations in the liquid phase.