Progress in Biochar Derived Adsorbents: Preparation, Modification Strategies, and Applications for Remediation of Antibiotics from Wastewater

Abstract

The increasing presence of antibiotic compounds in aquatic environments has become a serious concern due to their potential to promote antibiotic resistance and adversely affect ecosystems. Conventional treatment methods are often insufficient for the complete removal of these pollutants. In this context, biochar a porous carbonaceous material derived from biomass pyrolysis has attracted significant attention as a promising material for the remediation of antibiotics in wastewater. This review systematically highlights recent advances in the study of biochar including its sources and synthesis techniques such as pyrolysis, gasification, hydrothermal carbonization, and mild pyrolysis. It also explores various activation and modification strategies including physical and chemical activation, electrochemical techniques, and environmentally friendly modification approaches. Furthermore, the effects of operational parameters such as pH, temperature, duration time, biochar dosage, and pollutant concentration on uptake performance are thoroughly examined. The underlying adsorption mechanisms such as electrostatic interactions, ion exchange, π–π interactions, surface complexation, and capillary diffusion, are analyzed in detail. In addition, quantum chemical approaches, particularly density functional theory (DFT) are discussed for their role in elucidating the fundamental interactions between antibiotics and biochar materials. Finally, the review addresses current challenges, potential risks, and emerging trends in the development of hybrid biochar materials, particularly those incorporating MOFs and MXenes for effective antibiotic pollution control.