STUDY OF THE EFFICIENCY OF WATER PURIFICATION FROM HEAVY METAL IONS WITH MAGNETITE SORBENTS

The process of water treatment from heavy metal ions on sorbents with magnetic properties was investigated. Samples of magnetite obtained at a ratio of the concentrations of iron (II) ions and iron (III) 1 : 2; 1 : 1 and 2 : 1, and samples modified with sodium sulfide were used. The effect of pH on the sorption efficiency of heavy metal ions on magnetite was studied. It was shown that the sorption capacity of magnetite towards heavy metal ions, as well as the efficiency of water treatment from these compounds, increases with an increase of the [Fe2+]/[Fe3+] ratio from 1 : 2 to 2 : 1. Sorption capacity of magnetite increases with increasing pH due to partial hydrolysis of heavy metal ions. Also sorption capacity of magnetite increases significantly if modified it with guanidine, thiosemicarbazide, and sodium sulfide. At the same time, the sorbent provides a high degree of water purification from heavy metal ions while reducing the metal concentrations to several µg/dm3. Ref. 12, Fig. 5, Tab. 1.