OPTIMIZATION OF PHOTO-FENTON PROCESS FOR THE DEGRADATION OF BASIC RED 9: KINETIC ANALYSIS, INTERMEDIATE IDENTIFICATION, AND TOXICITY IMPLICATIONS

Abstract

The widespread use of synthetic dyes like Basic Red 9 (BR9) poses a significant threat to water resources. This study optimized the Photo-Fenton process for BR9 degradation, identifying pH 3.5 as the most critical parameter. The reaction followed pseudo-first-order kinetics, with the rate constant increasing from 0.012 to 0.019 min⁻¹ as temperature rose from 303 to 333 K. A low activation energy of 26.01 kJ/mol was calculated. GC-MS analysis identified Nonadecanamide and 9-Octadecenamide as primary intermediates, confirming the breakdown of the complex dye into simpler aliphatic amides. These findings demonstrate the process's effectiveness for decolorization and suggest a reduction in toxicity, offering a viable method for treating dye- contaminated wastewater, though further toxicological assessment is recommended.