Hydrothermal and pyrolytic conversion of sunflower seed husk into novel porous biochar for efficient adsorption of tetracycline

In this study, sunflower seed husk biochar prepared by ZnCl2-activated and hydrothermal carbonization (HZSF) was studied for its effectiveness in removing tetracycline (TC) from an aqueous solution. The physical and chemical properties of materials were characterized by different methods of surface analysis. The specific surface area of HZSF is significantly enhanced over 1200 times compared with non-modified biochar (HZSF: 1578.3 m(2)center dot g(-1), SF-700: 1.3 m(2)center dot g(-1)), which has an enhancement effect on the TC adsorption capacity. The HZSF showed that the Langmuir isotherm and pseudo-second-order kinetic models could properly characterize the adsorption processes. In the Langmuir isotherm model, HZSF exhibited effective adsorption performance with qmax of 673.0 mg center dot g(-1) at 298 K for 24 h. The possible mechanisms for the adsorption process were the monolayer, chemical adsorption, and the participation of strong intermolecular forces. In general, HZSF has the potential to be a useful adsorbent for the elimination of antibiotics from water-based solutions.

Automated summary

In this study, the effectiveness of sunflower seed husk biochar (HZSF) prepared by ZnCl2-activated and hydrothermal carbonization in removing tetracycline (TC) from an aqueous solution was studied. The physical and chemical properties of the materials were characterized using different surface analysis methods. The specific surface area of HZSF was significantly enhanced compared to non-modified biochar, resulting in improved TC adsorption capacity.