TREATMENT OF WASTEWATER USING A SORBENT BASED ON THERMALLY ACTIVATED OPOKA MINERAL AND CHEMICALLY MODIFIED CAMELTHORN TREE

Abstract

In our study, the treatment processes of wastewater from “Elektrokimyozavod” JSC were investigated using a combination of thermally activated opoka (0.5%) and sorbent based on camelthorn tree chemically modified in an alkaline medium. It was found that increasing the amount of sorbent had a clear effect on the residual content of heavy metal ions. When the camelthorn tree sorbent was added at 0.04%, the concentration of metals in the water was high, with Cu – 14.49 mg/l, Ni – 19.20 mg/l, Co – 2.48 mg/l, Zn – 0.48 mg/l, Sr – 0.28 mg/l, and Cr – 1.20 mg/l. When the sorbent amount was increased to 0.08%, a decreasing trend was observed for all elements: Cu decreased to 8.43 mg/l, Ni to 11.88 mg/l, Co to 1.66 mg/l, Zn to 0.29 mg/l, Sr to 0.17 mg/l, and Cr to 0.81 mg/l. These results indicate that in an alkaline medium, the porous structure of the chemically modified camelthorn tree sorbent opens up, and its active hydroxyl and carboxyl groups begin to bind metal ions. At this stage, the sorption process becomes more active, meaning the active sites of the sorbent exhibit strong adsorption capacity toward metal ions. In the next stage, when the sorbent was added at 0.1%, the residual concentrations of all elements sharply decreased, reaching Cu – 2.37 mg/l, Ni – 4.57 mg/l, Co – 0.83 mg/l, Zn – 0.11 mg/l, Sr – 0.05 mg/l, Mo – 0.29 mg/l, and Cr – 0.43 mg/l. These results show that precisely at a sorbent amount of 0.1%, the camelthorn tree sorbent demonstrates a synergistic effect with thermally activated opoka.