GREEN SYNTHESIS AND CHARACTERIZATION OF TiO2 NANOPARTICLES USING BIO-WASTE EXTRACTS FOR PARACETAMOL PHOTODEGRADATION

Pharmaceutical residues such as paracetamol are increasingly detected in aquatic environments, posing ecological risks and demanding sustainable removal strategies. In this study, TiO₂ nanoparticles were synthesized via a green route using bio-waste such as avocado peel, petai pod, and pomelo peel ethanol extracts as natural capping and stabilizing agents. FT-IR analysis confirmed the presence of phenolic and flavonoid groups, while UV-DRS revealed slight variations in band gap energy (3.18 - 3.27 eV), with TiO₂-EEPPo exhibiting the narrowest band gap. XRD patterns showed that all samples were dominated by the anatase phase with crystallite sizes of 9.9 - 17.7 nm, and FE-SEM/PSA analysis demonstrated nanoscale particle sizes (23 - 98 nm) with porous but agglomeratedmorphologies. Zeta potential values (-17.11 to -24.16 mV) indicated sufficient colloidal stability, while adsorption studies highlighted improved affinity in biowaste-modified TiO₂ due to hydroxyl, carboxyl, and phenolic groups. Photocatalytic degradation experiments demonstrated that photolysis alone removed only 36.52 % of paracetamol after 180 min. Biowaste-modified catalysts also exhibited high efficiencies, with TiO₂-EEPA, TiO₂-EEPPi, and TiO₂-EEPPo degrading 91.75 %, 90.1 %, and 95.89 %, respectively, under UV irradiation. These findings confirm that agro-waste-derived extracts not only enhance the structural and photocatalytic properties of TiO₂ but also provide an eco-friendly approach for pharmaceutical wastewater remediation and bio-waste valorization.