ИСТИНА

Pollution of natural waters is of urgent environmental concern. Heavy metals are among the most widespread pollutants and pose particular danger to human health. An advanced method for cleaning water from metal pollution is a use of magnetic nanosorbents. The main problem in their production is stabilization in solution. Natural polyelectrolytes - humic substances (HS) - have great potential for solving this problem. In this regard, the purpose of this work was to synthesize magnetite nanoparticles in the presence of humic substances for cleaning water contaminated with heavy metals. To achieve this goal, the following tasks were to solve: An optimal method for synthesizing magnetite nanoparticles in the presence of humic substances was developed by varying the conditions for its production. It was shown that the optimal precursors are FeCl3 and FeSO4, the precipitant is ammonia, an inert atmosphere and humate of oxidized coal with a high content of phenolic groups. In the presence of this humate, the minimum sizes of nanoparticles were observed. A study of their phase composition and size was performed using TEM and SEM. It was shown that the size of magnetite nanoparticles synthesized under the optimal conditions found was 5-10 nm. To characterize the functional properties of magnetite nanoparticles stabilized by HS, their sorption capacity for copper and nickel ions was studied. It was shown that magnetite has a much higher sorption capacity for copper than for nickel: 48 and 7 mg/g, respectively. Conclusions 1. Optimal conditions for obtaining a pure phase of nanosized magnetite in the presence of HS were found: a use of ammonia as a precipitant and a use of inert atmosphere for carrying out the synthesis 2. The higher sorption capacity of magnetite nanoparticles obtained in the presence of HS for copper and nickel was shown, while the contribution of the humic component increases with an increase in the total acidity of the original humate. Acknowledgements. This research was carried out within the framework of the state task “Ecology” (no. 122040600057-3).