Aplicação de um reator eletroquímico em fluxo através de um ânodo de Ti/RuO2 na degradação de compostos orgânicos presentes em um efluente sintético contaminado por derivado de petróleo

Abstract

Contamination by organic oil derivatives has become increasingly common in nature and treatment methods are periodically sought to remedy this type of contamination. Electrochemical reactors are being studied in order to optimize the various types of electrochemical treatments. Through the study of the reactor hydrodynamics, it was possible to observe a predominantly turbulent flow regime with an experimental mass transport constant higher than the theoretical one, indicating that the mass transfer is not homogeneous due to the presence of gases generated in the electrodes. Electro-oxidation using DSA (Ti/RuO2) electrodes, due to their low cost, greater durability and relative efficiency, has been studied in the removal of organic substances derived from petroleum. The complete factorial design was employed as a statistical technique in order to evaluate the best conditions for the development of the synthetic effluent, analyzing the miscibility of diesel in a saline matrix, as well as to verify the best conditions employed in the electrochemical reactor on the main factors worked and its effects on the electro-oxidation of this saline matrix contaminated with diesel. From the prepared synthetic effluent, it was possible to apply electro-oxidation as a treatment technique in a tank-type bench reactor in direct flow through a Ti/RuO2 anode and a titanium cathode, both mesh type, arranged parallel to each other and perpendicular to the reactor. Through the TOC analysis, Test 6 with a current density of 50 mA/cm2 , initial pH 3 and NaCl concentration of 70 mM, showed the best result, with 63% mineralization, as it could also be followed through the spectra of fluorescence and UV absorption, indicating the reduction of the bands corresponding to the organic compounds present. The UV-Vis spectrum also showed the presence of active chlorine substances, electrochemically generated compounds during the electrochemical process using this type of anode.