Моделирование процесса адсорбции в системе жидкость – твердое тело: регрессионный анализ извлечения меди из водных растворов цеолитом Холинского месторождения, модифицированным серосодержащим полимером

Abstract

This article describes the formation of an effective sorbent for heavy metal ions by modifying natural zeolite (clinoptilolite type, Kholinskoye deposit). The modification was carried out by applying the network of a sulphur-containing polymer on the zeolite surface. For the formation of a polymer network, elemental sulphur was dissolved in the hydrasine hydrate–monoethanolamine system to generate polysulphide anions (in particular, S2 2- ). During the contact of the obtained sulphur solution with zeolite, polysulphide anions and the monoethanolamine entering the zeolite pores were concentrated on the surface. Further polycondensation of S2 2- anions with 1,2,3-trichloropropane (epichlorohydrine production waste) resulted in the formation of a reticulated sulphur-containing polymer covering the zeolite surface. Such a sorbent provides immediate solution to the problems concerned with utilisation of organochlorine wastes and purification of technological media containing heavy metals. Extraction of metals by the obtained sorbent was studied using model solutions with a metal concentration of 5000 mg/L. Encouraging results were obtained for five metals. Detailed information on the extraction of copper ions from aqueous solutions is presented. Experimental data was obtained on the effect of pH on the sorption efficiency of copper ions, as well as on the thermodynamic and kinetic characteristics of adsorption under static and dynamic conditions. The complex coordination mechanism of Cu (II) sorption by modified zeolite was confirmed using IR-spectroscopy. Since the thermodynamic and kinetic dependencies frequently deviate from the classical laws during sorption by the complex coordination mechanism, regression analysis was used to process the experimental data. As the result, nonlinear models were obtained fairly accurately describing experimental data on the extraction of copper ions by modified zeolite. The obtained regression models can be applied in further research of the new sorbent and in designing installations for extracting copper compounds from technological media.