Nanocellulose aerogels for antibiotic removal: Sustainable adsorbents with enhanced performance and regeneration potential

The widespread presence of antibiotics in aquatic environments has raised significant concerns due to their toxicological and biological effects, which present substantial risks to human health. This study addresses the challenge of antibiotic contamination by investigating the adsorption mechanisms and performance of nanocellulose-based aerogels as sustainable adsorbents for antibiotic removal from water. Nanocellulose aerogels were fabricated using hydrothermal gelation, solvent exchange and freeze-thaw techniques and characterized by SEM and FTIR analyses. Batch adsorption experiments were conducted to evaluate the effects of aerogel concentration, pH, contact time and initial trimethoprim (TMP) concentration on adsorption efficiency. Key findings indicate that CNC aerogels with higher nanocellulose concentrations exhibited increased adsorption capacities, with the 8 % CNC aerogel achieving the highest TMP removal efficiency within the initial 0–30 min of adsorption. The adsorption process was strongly influenced by pH and contact time, with optimal removal observed at acidic pH and equilibrium reached within 90 min. Solvent exchange using tert-butanol significantly enhanced the structural integrity and adsorption performance of the aerogels compared to those prepared without solvent exchange. The results demonstrate that nanocellulose aerogels are promising, sustainable adsorbents with high efficiency and regeneration potential for antibiotic removal from contaminated water sources.