Estudo do processo híbrido de eletro oxidação e eletrocoagulação por dissolução catódica no tratamento de efluente têxtil

Abstract

The use of electrochemical methods in the treatment of industrial effluents is a promising alternative to traditional methods, as the efficiency in removing pollutants provides satisfactory results in industries and treatment plants. However, electricity consumption and high initial costs are still factors that prevent its widespread use. In this sense, the present work aims to study an alternative method in the use of electrochemical cells to increase efficiency in relation to known methods: electrochemical oxidation with electrocoagulation by cathodic dissolution. It is a hybrid method, using two traditional processes (electrocoagulation and electrooxidation) but innovating in the disposition of the electrolytic cell to obtain better results. To study the process, the effects of initial pH (4, 7 and 10), anode type (graphite and Ti/Pt) and supporting electrolyte (NaCl, NaNO3 and Na2SO4) were initially evaluated in preliminary tests, then, the efficiency comparison of the proposed method with the methods already known in the literature in the removal of synthetic textile effluent (Red Remanzol RB 133%) were made. During the experimental procedure, analyzes of dissolved organic carbon, color, pH, cathode mass and energy consumption were performed. The results obtained provided the following optimal operating conditions in the preliminary tests: pH 4, Ti/Pt anode and NaNO3 as supporting electrolyte. In comparative tests, the hybrid method proposed in the present work showed better efficiency in color removal (100%), dissolved organic carbon (69.71%), energy consumption and electrode consumption compared to traditional methods of electrocoagulation and electro-oxidation applied separately, demonstrating that the technique is a promising alternative to traditional methods in the treatment of water and effluents.