NaOH-activated Pomegranate Peel Hydrochar: Preparation, Characterization and Improved Acebutolol Adsorption

Environmental requirements include sustainable materials with low investment costs and high performance for water treatment applications. The process of hydrothermal carbonization, on the other hand, offers a quick, economical, and green way to transform waste from natural resources into sustainable products. This study aims to produce a novel hydrochar-based material from pomegranate peel using NaOH cold-alkali activation. Extensive physicochemical characterization of the obtained material (NaOH-HCPP) was conducted. To assess the ability of NaOH-HCPP to remove acebutolol (ACE) drug from an aqueous solution, batch adsorption tests were performed, reaching (97.25 mg g −1 ) under optimal parameters. The isotherm fit best with the Freundlich model, whereas the kinetics were well described by both the PSO and Elovich models, indicating that the process was physicochemical. Moreover, thermodynamic studies stated that acebutolol uptake was distinguished by spontaneity (Δ G ° < 0) and exothermicity Δ H ° (− 31.91 kJ mol −1 ). Furthermore, a discussion of the empirical results and further analysis revealed that ACE adsorption onto NaOH-HCPP is controlled by pore filling, van der Waals forces, electrostatic attraction, hydrogen bonding, π–π, and n–π interactions. Thus, NaOH-HCPP has demonstrated high promise for removing acebutolol and possibly other pharmaceuticals from aqueous media.