Physicochemical Properties and Application of Silica-Doped Biochar Composites as Efficient Sorbents of Copper from Tap Water

This article concerns research on new sorption materials based on silica-doped activated carbon. A two-stage synthesis involved pyrolysis of plant material impregnated in a water glass solution, followed by hydrothermal activation of the pyrolysate in KOH solution. The resulting composite can be used as a sorbent in drinking water filters. The proposed method of synthesis enables the design of materials with a surface area of approximately 150 m(2).g(-1), whose chemical composition and structure were confirmed by scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS), X-ray diffraction (XRD), thermogravimetry/differential thermal analysis (TG/DTA) and Fourier-transform infrared spectroscopy (FTIR). The sorption properties of the obtained materials were determined relative to copper ions using the batch experiment method. The optimal operating parameters of the obtained materials relative to copper ions are T = 313.15 K, pH = 5, S:L ratio = 4 g.dm(3) and t = 120 min. The research shows that the sorption kinetics of copper ions can be described by a pseudo-second-order model. The plotted copper(II) sorption isotherm clearly indicates the Langmuir model. Under optimal conditions, the maximum sorption of copper ions was 37.74 m.g(-1), which is a satisfactory result and confirms the possibility of using the obtained material in drinking water filters.

Automated summary

This study focuses on the research of new sorption materials based on silica-doped activated carbon. A two-stage synthesis process was used, involving the pyrolysis of plant material impregnated in a water glass solution, followed by hydrothermal activation in KOH solution. The resulting composite showed potential as a sorbent in drinking water filters. The research confirmed the material's surface area, chemical composition, and structure through various analysis methods. The optimal operating parameters for the sorption of copper ions were determined, as well as the sorption kinetics and isotherm models. The maximum sorption capacity of copper ions was found to be 37.74 m.g(-1), indicating the potential use of the material in drinking water filters.