Aplicação do processo de eletrocoagulação-peroxidação (ecp) no tratamento de fármacos em efluente sintético

Abstract

In today's society, there is a notable increase in concern about water resources. In view of this statement, several ordinances and legislation determine standards and conditions for the discharge of effluents into bodies of water. However, there are several contaminants that are not covered by these guidelines because they are found in low concentrations and due to little knowledge of their long-term effects. These contaminants are called emergents, and this category includes drugs such as antibiotics, anti-inflammatories, antidepressants, hormones, among others. There are studies that indicate the low biodegradability of these compounds in the environment and their high toxicity to living organisms, including humans. Conventional water treatment plants do not have steps dedicated to the removal of these compounds, making it necessary to develop techniques capable of degrading or removing these contaminants, associating low cost with high efficiency. The electrocoagulation process associated with advanced oxidation appears as an alternative to effluent treatment processes. In this context, the objective of this work was to evaluate the electrocoagulation process associated with peroxidation, using iron scrap as sacrificial electrodes, in the treatment of synthetic effluents containing the drugs Ibuprofen and sodium Diclofenac. Peroxidation electrocoagulation (ECP) performance evaluation was carried out using the hydrogen peroxide oxidizing agent (H2O2), in order to enhance the removal of these drugs, as this associates the electrochemical process with the advanced oxidation process, and thereby define the ideal treatment conditions. High performance liquid chromatography (HPLC) was used to quantify drugs in synthetic effluents. The experimental design was used the DCCR 24, composed of 28 tests, with the independent variables being evaluated the concentration of contaminants, the current, the concentration of the primary oxidizing agent H2O2 and the reaction time. Analysis of variance (ANOVA), response surface graphs, contour curves and global desirability served as a basis for determining optimized treatment conditions. The optimized conditions determined by statistical analysis were drug concentration of 5 mg.L-1, H2O2 concentration of 200 mg.L-1, current of 5 A and 150 min. The removals obtained under these conditions were greater than 92% in the aqueous phase, showing that this ECP technique has the potential to treat contaminants such as drugs present in effluents and waters.