SORPTION OF HEAVY METALS BY MULTICOMPONENT FOAM POLYMER SORBENTS

The article is dedicated to the investigation of the sorption of heavy metals from water bodies by foam polymer sorbents obtained on the basis of multicomponent polymer mixtures. The need for such studies was dictated by the fact that the more diverse the content of functional or polar groups became in the composition of the foam polymer sorbent, the greater was the probability of increasing the efficiency of sorption of heavy metals. Biocomponent polymer mixtures based on polyamide + polyurethane and three-component mixtures polyamide + polyurethane + acrylonitrile-butadiene-styrene copolymer were used as polymer matrix of the foam polymer sorbents at various ratios. Depending on the chemical nature and the ratio of the initial components in the macromolecules of polyurethane, polyamide and acrylonitrile-butadiene-styrene copolymer, in addition to urethane groups, functional groups such as ether–, ester, amide, urea, and also aliphatic and nitrile groups are also present. The investigation results of the kinetic regularities of heavy metals sorption under polymer components different ratios and ambient temperature are presented. It is established that the foam polymer sorbent consists of pores and cells with a membrane structure, which allows using it for effective sorption of polar and nonpolar compounds. The concentration of sorbed heavy metals was determined by UV-spectroscopic analysis. It is shown that the presence of a system of pores and cells allows the sorbate to diffuse into its more deeply located regions, as a result of which sorption occurs throughout the volume of the sorbent. Essentially, the foam polymer sorbents sorb the molecules by dissolving them on the surface of their membranes. A large variety of adsorption centers on the surface and in the bulk of the foam polymer causes a whole complex of sorbent-sorbate interactions, among which the Van der Waals interactions, dispersion interactions, electrostatic interactions and hydrogen bonds are the main ones.