Expérimentation de procédés innovants à base de persulfate pour l’élimination des colorants textiles

Abstract

Dyes are extensively used across various industries, including printing, food, cosmetics, healthcare, and especially textiles, due to their chemical stability, relatively straightforward manufacturing process, and a broad spectrum of colors. However, their discharge into the environment is a significant source of pollution, creating a need for processes that can reduce the dye load in effluents. In this study, two advanced oxidation processes (AOPs), Fe0/KPS and Fe0/UV/KPS, were evaluated for the removal of a textile dye, Basic Yellow 13. We compared the performance of these two systems, focusing on the impact of various experimental conditions, such as pH, initial concentrations of dye, oxidant, and catalyst. Additionally, we investigated the influence of different additives, such as salts and surfactants, on dye degradation, along with the role of radical scavengers in determining the dominant reactive species, such as SO4•⁻ and •OH. The effect of different matrices and the reusability of iron on the efficiency of potassium persulfate-based processes were also assessed. The results showed that the immersion depth of the UV lamp significantly affects the efficiency of the Fe0/UV/KPS system. A greater ozone generation in this system correlates with more effective dye degradation. Optimal conditions for Basic Yellow 13 removal were identified, yielding removal rates of 96,7% and 88.23% for the Fe0/KPS and Fe0/UV/KPS systems, respectively. Regarding mineralization, the Fe0/UV/KPS system was more effective than Fe0/KPS in completely degrading organic compounds. Although both systems were found to be effective, the addition of the UV lamp in the Fe0/UV/KPS system enhanced the degradation of Basic Yellow 13. Given these promising outcomes, these two- potassium persulfate based AOP systems warrant further consideration, as they are relatively simple to implement and use low-cost reagents, like iron powder and potassium persulfate.