STUDIEREA PROCESULUI DE DIMINUARE A CONCENTRAŢIEI COLORANŢILOR DIRECŢI DIN SOLUŢIILE-MODEL PRIN APLICAREA METODELOR FIZICO-CHIMICE

Abstract

The process of removal of textile coloring agents from model solutions by means of consecutive electrochemical andcatalytic oxidative treatment in the presence of hydrogen peroxide, and its dependence of the amount of electrochemical coagulant, initial concentration and properties of the coloring agent as well as the iron ions (II) content was discussed incurrent paper. The obtained results prove that the removal of reactive colorants through electrical generation of coagulants is more effective and economically sound when carried out from more concentrated model solutions of textile residual waters (the initial concentration should between 150-200 mg/l). The application of catalytic oxidation procedure can be applied in case of removal of reactive colorants of less concentrated solutions (the amount of colorants should not exceed 50 mg/l). From the acquired results it was identified that combined methods of electrochemical removal and catalytic oxidation by hydrogen peroxide of reactive colorants assure their effective removal from model solutions of residual waters containing up to 200 mg/l of mentioned colorants. The mineralization and residues content were reduced by 97-98%, while the consumption of coagulant was lower by a factor of 2-2.5 in comparison with conventional methods of treatment.