Degradation of residual dyes in actual textile wastewater using UV/H<sub>2</sub>O<sub>2</sub>: Evaluation of the impact of operating variables through multi-layer perceptron analysis

Abstract

UV/H<sub>2</sub>O<sub>2</sub> is a commonly used advanced oxidation process for removing non-biodegradable organic compounds. However, additional efforts are needed to understand the relative significance of operational factors during the UV/H<sub>2</sub>O<sub>2</sub>. Here, we investigated the effect and specific contribution of crucial factors such as H<sub>2</sub>O<sub>2</sub> concentration, UV intensity, and reaction time on the color and total organic carbon (TOC) removal efficiency in textile wastewater using the one-factor-at-a-time method and multi-layer perceptron (MLP) analysis. The results showed that color removal was enhanced with high H<sub>2</sub>O<sub>2</sub> concentration, high UV intensity, and long reaction time. Overall, more than 99% removal of color was achieved by the UV/H<sub>2</sub>O<sub>2</sub>, utilizing the following parameters: H<sub>2</sub>O<sub>2</sub> concentration of 5 mM, UV intensity of 26.6 W/m<sup>2</sup>, and reaction time of 180 min. On the other hand, the removal of TOC was increased by high H<sub>2</sub>O<sub>2</sub> concentration and long reaction time, but not by high UV intensity. In the MLP analysis, the H<sub>2</sub>O<sub>2</sub> concentration was identified as the primary factor affecting both color and TOC removal, accounting for 43% and 50% reduction of the color and TOC, respectively. Overall, this study helps to understand the relative importance of the most critical operating factors in treating actual textile wastewater by the UV/H<sub>2</sub>O<sub>2</sub>.