Elimination et dégradation des produits récalcitrants par des matériaux synthétiques : application des micro-ondes et de la photocatalyse homogène et hétérogène

Abstract

This work was carried out in order to evaluate the various processes of the homogeneous and heterogeneous Fenton-like to degrade the patent blue V as pollutant (PBV) model in aqueous solution. The first process studied is the homogeneous photo Fenton-like using iron and copper in the presence of the H2O2. The results obtained show that Fe3+ is most effective in comparison with Cu2+. The study of the different parameters revealed that the UV, the pollutant concentrations and the Fenton reagents concentrations (catalyst and oxidant) have a significant impact on the process performance. In the second process, synthetic materials (hydrotalcits and derevatives) contain the transition metals iron and copper were tested. In this case, the degradation of PBV is followed by a different and more complicated mechanism. The synthesized materials are characterized by several methods (pHpzc, DRX, FTIR, granulometry, UV-DRS, ATG/ATD, MEB- EDX). In addition, the main parameters that can affect the degradation efficiency have been studied. The stability of the solids was evaluated by determining iron and dissolved copper concentrations and reuse in successive cycles. The homogeneous and heterogeneous Fenton-like process assisted by the irradiation of microwaves shows a remarkable efficiency for the degradation of the patent blue V, in particular a high degradation rate in a very short treatment time (a few minutes). The proposed reaction mechanisms of each process are explained in detail to demonstrate all the reactions and interactions between the reagents, the catalysts, the target molecule and the intermediates ... etc.