Regresar

Degradation of Pollutants from Sanitizer Industries via Advanced Oxidation Processes: Comparison Between Classical and Electrochemical Systems

Abstract:

In this work, we investigated the degradation of the mixture of acid yellow 36 and acid blue 80 via photoperoxidation (PP/UV-C) and via electrochemical oxidation (EAOP). After optimization, the best results were obtained using [H2O2] = 80 mg‧L−1 for PP/UV-C and concentrations of 0.05 mol∙L−1 of the electrolytes (Na2SO4 and KCl) for EAOP/UV-C. For PP/UV-C, complete degradation of the monitored groups was obtained for all 3 λ. For the electrochemical systems, the higher degradation efficiency was achieved by using UV-C radiation associated with the electrochemical absorption process (EAOP/UV-C), reaching 75% for 267 nm and 100% for the other λ from 180 min. A kinetic monitoring by HPLC analytical technique was performed in order to visualize the possible reaction intermediates, as well as the consumption of H2O2 and the production of chlorine compounds as oxidizing agents of the applied processes. The toxicity evaluation against Nasturtium officinale, Daucus carota subsp. Sativus, and Thymus vulgar seeds and for Escherichia coli showed the presence of intermediate species of the dyes due to a certain degree of post-treatment toxicity. It was concluded that the use of the PP/UV-C and EAOP processes was efficient for the degradation of the dyes studied, although the system must be further improved to achieve better mineralization.