Section: Chemistry of natural environments and objects
Comprehensive wastewater treatment from various pollutants is an urgent problem, and the development of new sorbents is of great scientific and practical importance. Sorbents based on sapropel were obtained: thermally oxidized sapropel, humic acids isolated from sapropel, thermally oxidized sapropel modified with humic acids, organomineral composite material based on thermally oxidized sapropel and bentonite. Resorcinol adsorption from model solutions with concentrations from 1 · 10-5 to 1 · 10-2mol/dm3 onsapropel-based sorbents was carried out under static conditions at a ratio of 1 g of sorbent per 200 cm3 of solution. It is shown that the limiting stage of resorcinol adsorption onsapropel-based sorbents is mixed diffusion. The adsorption theories of Langmuir, Freundlich, Brunauer–Emmett–Teller (BET) and Dubinin–Radradkevich are applicable to describe the resorcinol adsorption onsapropel-based sorbents. Taking into account the values of the activation energy and thermodynamic parameters of resorcinol adsorption, the obtained sapropel-based sorbents can be considered as the mechanism of resorcinol adsorption on the surface and physical adsorption due to volumetric filling of micro- and mesopores, as well as cavities. Resorcinol can also form covalent and hydrogen bonds with silicate and aluminosilicate groups, and hydrogen bonds with amino groups with sapropel-based sorbents. Therefore, it is quite difficult to separate the contribution of physical adsorption and possible chemical interactions of functional groups of sapropel-based sorbents with resorcinol. Limiting values of resorcinol adsorption onsapropel-based sorbents calculated by the BET equation (0.25–1.00 mmol/ g) and the Dubinin–Radushkevich equation (0.52–2.60 mmol/g), comparable to other developed sorbents.
ISSN 1995-4301
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