Özcan, ZeynepSönmez, GamzeIşık, Mustafa2025-09-172025-09-17202518630650https://doi.org/10.1002/clen.70035https://hdl.handle.net/20.500.12451/14436The Fenton and UV–Fenton procedures were utilized in this study to eliminate total organic carbon (TOC) from wastewater generated during actual resin manufacturing. Optimal operating parameter values influencing removal efficiency were identified, including initial H2O2 and Fe2+ concentrations and total reaction time (t). The residual H2O2 concentration was measured using the metavanadate method in all processes. The results indicated that the Fenton process achieved a TOC removal rate of 32.0% at concentrations of 500 mg L−1 for H2O2 and 100 mg L−1 for Fe2+, with a constant pH of 3.78 and a reaction time of 6 h. In the UV–Fenton process, H2O2 concentrations of 500 and 1000 mg L−1 were examined, resulting in 14% and 15% TOC removal efficiencies, respectively. The effect of gradually adding H2O2 on the removal efficiency was also investigated in this study. To do this, the Fenton process started with an initial H2O2 concentration of 250 mg L−1. Once approximately 80% of this amount was consumed, 250 mg L−1 H2O2 was added, and the process continued. A maximum TOC removal of about 71% was achieved by gradually adding H2O2 at a 4000 mg L−1 concentration. On the basis of these findings, the gradual addition of H2O2, as opposed to an initial dose, proved to be a significant and practical method for removing organic matter from wastewater in the Fenton process. © 2025 Wiley-VCH GmbH.info:eu-repo/semantics/closedAccessAdvanced Oxidation ProcessFentonResidual H2O2Resin Wastewater53810.1002/clen.700352-s2.0-105013999796Q3WOS:001560861200009Q4