Photo-degradation of sugar processing wastewater by copper doped bismuth oxyiodide: Assessment of treatment performance and kinetic studies

In this study, photo-Fenton-like oxidation method was evaluated for synthetic sugar industry wastewater using visible-light driven Cu-BiOI photocatalyst. Reaction conditions including initial pH, catalyst loading, initial hydrogen peroxide (H2O2) concentration, and temperature, were optimized. At these optimized conditions, the total saccharide concentration (TSC) and total organic carbon (TOC) removals were 56.20% and 30.67%, respectively whereas the maximum TSC and TOC removal reached up to 93.35% and 74.72% respectively by decreasing initial sucrose concentration. The kinetic study showed that the reaction order for sucrose and TOC oxidation was determined as 2 for pseudo-homogeneous power law models with respect to sucrose concentration and TOC, respectively.For heterogeneous models, Langmuir-Hinshelwood model based on the mechanism of adsorbed pollutant and oxidant on different catalytic sites was the best fit for oxidation of sucrose and other organic intermediates. According to the catalyst characterization studies, incorporation of copper was successful and Cu-BiOI possesses high photocatalytic activity accomplished by acid-assisted synthesis method.

Automated summary

In this study, the photo-Fenton-like oxidation method using visible-light driven Cu-BiOI photocatalyst was evaluated for synthetic sugar industry wastewater. The reaction conditions were optimized and achieved high removal rates by reducing the initial sucrose concentration. The kinetic study revealed the reaction order and the best fit models for sucrose and TOC oxidation.