Evaluation and comparison of Fenton-like oxidation with Fenton's oxidation for hazardous methoxyanilines in aqueous solution

Methoxyanilines are aniline derivatives that are important chemical precursors for numerous Dye and Pharmaceuticals industries. Wastewater containing methoxyanilines have high toxicity and carcinogenic properties and if discharged without prior treatment into fresh water resources, can result in possible detrimental eff;ects to aquatic life and public health. Therefore, in this work Fenton-like oxidation was evaluated for the degradation of 2-methoxyaniline (2-MA) and 4-methoxyaniline (4-MA) separately using abundantly available Laterite soil as an alternative source of iron against commercially procured iron (CI) in Fenton-oxidation. Parameters like hydrogen peroxide (H2O2), iron and initial methoxyanilines concentration were investigated for each of the methoxyanilines in separate experiments. For initial methoxyanilines concentration of 0.5 mM, the maximum methoxyanilines removal of 83.28 +/- 0.26% and 86.34 +/- 0.34% and COD removal of 71.91 +/- 0.31% and 72.64 +/- 0.29% for 2-MA and 4-MA at pH 3 and pH 2.5 was attained at laterite soil iron [LSI] of 0.05 mM respectively. From kinetic studies of 2-MA and 4-MA, reaction time was estimated to be 360 min. Degradation with LSI was found to be slower and lesser than CI, but is comparable and can be applied as a replacement of CI for treatment of wastewater containing toxic and incalcitrant chemicals. (C) 2020 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.