SORPTION OF FERUM IONS ON NATURAL AND MODIFIED CLINOPTYLOLITE. INFLUENCE OF OXYDANTS

Abstract

The health of the population depends on the state of the environment, so the study of opportunities to improve the condition of water, air and soil does not lose its actual.
 The presence of substances in waters in concentrations is higher than the maximum permissible concentration can be caused by both human economic activity and the peculiarities of the geological structure of the lithosphere of the region. For example, high iron content is observed in the natural waters of many regions of the world. Although iron is an important element in human life, its excess in the body can cause many diseases.
 Removal of iron ions from water has a high cost, so reducing the cost of this process is an urgent issue. One of the options to reduce the cost of the process is to use natural zeolites, such as clinoptilolite. One of the largest deposits of clinoptilolite in Europe is located in the village Sokyrnytsia, Transcarpatian region.
 In this work, the sorption of iron ions on the natural clinoptilolite of the Sokyrnytsia deposit and its modified forms under static conditions has been studied. Any of the proposed modification methods has a positive effect on the sorption properties of clinoptilolite with respect to iron ions, the amount of Fe ions sorption increases for hydrogen form by 30%, ammonium form by 60% and sodium form by 65% are shown.
 The influence of oxidants (hydrogen peroxide) on the sorption of iron ions on clinoptilolite of the Sokyrnytsia deposit (Ukraine) has been studied. The significant influence of iron oxidation before sorption on the growth of its extraction from water by natural clinoptilolite is shown, which is confirmed by thermodynamic calculations performed by the semi-empirical method GFN2- xTB (density functional theory), which indicate that only ion exchange reaction involving Fe3+. And if the exchange ion is a Na+ ion, ion exchange sorption can occur with both Fe3+ and Fe2+.
 Isotherms of ion-exchange sorption of iron in the range of concentrations from 0.05 mmol/l to 1 mmol/l are well described by the Langmuir equation. Sorption isotherms in the coordinates 1 / A = f (1 / C) are linear.
 Keywords: clinoptilolite; iron; ion exchange; oxydants.