Synthesis and characterization of Opoka–Ailanthus charcoal composite sorbents for industrial wastewater treatment

This research aims to develop effective, import-substituting carbon-mineral composite sorbents for treating industrial wastewater using local raw materials: Opoka mineral from the Navoi region and charcoal derived from Ailanthus ( Ailanthus altissima ) wood. During the study, samples were prepared by mixing Opoka and Ailanthus charcoal in mass ratios of 95:5, 90:10, 85:15, 80:20, 75:25, 70:30, and 65:35, followed by thermal activation in the temperature range of 400°C to 900°C for 30 minutes. The chemical and mineralogical compositions of the sorbents were analyzed using X-ray fluorescence, X-ray diffraction, and IR spectroscopy methods. It was determined that the initial Opoka mineral primarily consists of SiO2 (64.0%), CaO (15.7%), AhO3 (12.1%), and Fe2O3 (5.15%) and possesses a porous structure. The results indicated that as the activation temperature increased and the organic component (Ailanthus charcoal) was combusted, the content of metal oxides in the sorbent composition increased. Specifically, when the composite with an 85:15 ratio was activated at 750°C, the content of calcium oxide (CaO) increased to 26.73%, magnesium oxide (MgO) to 18.30%, and silicon oxide to 4.66%. The synthesized sorbents demonstrated high efficiency in reducing water hardness (calcium and magnesium ions) and removing heavy metals from industrial wastewater.

Hali tarjima qilinmagan