Preparation of a chelating sorbent based on pyridylethylated polyethylenimine for recovering transition metal ions

A method was developed for preparing a chelating amino polymer, pyridylethylpolyethylenimine with maximal degree of substitution, by polymer-analogous transformations of branched polyethylenimine in reaction with 2-vinylpyridine. The ability of cross-linked pyridylethylpolyethylenimine with the degree of substitution of 0.32 to sorb Cu²⁺, Ni²⁺, Co²⁺, Zn²⁺, Cd²⁺, Mn²⁺, and Pb²⁺ ions present simultaneously in solution was evaluated. In an ammonium acetate sorption system (pH 3.5–4.0), the sorbent selectively interacts with Cu(II) ions.