Sorption extraction of Cu<sup>2+</sup>, Co<sup>2+</sup>, Ni<sup>2+</sup> and Pb<sup>2+</sup> from aqueous solutions by tetrazole polymers based on commercial acrylonitrile copolymer
The sorption activity of tetrazole-based polymers prepared from commercial copolymer of acrylonitrile, methyl acrylate and 2-acrylamido-2-methylpropanesulfonic acid was studied in relation to Cu<sup>2+</sup>, Co<sup>2+</sup>, Ni<sup>2+</sup> and Pb<sup>2+</sup> in diluted aqueous solutions. It was found that the sorption capacity grew with increasing the tetrazolation ratio and the specific surface area of polymer. The possibility of selective sorption of Cu<sup>2+</sup> in the presence of Co<sup>2+</sup> was shown. The recovery of the sorbent after ion exchange sorption was achieved by treating with dilute hydrochloric acid.