Avaliação do uso da eletrocoagulação aplicada ao tratamento de água sintética contendo o contaminante emergente ácido acetilsalicílico

Abstract

The presence of emerging contaminants in water bodies has become an increasing challenge for wastewater treatment, particularly due to the low efficiency of conventional methods in removing substances such as pharmaceuticals. Among these, acetylsalicylic acid (ASA) stands out due to its widespread use and potential environmental impact, justifying the investigation of alternative treatment techniques. In this context, the present study aimed to evaluate the removal of acetylsalicylic acid from synthetic water through the electrocoagulation process using aluminum electrodes. The experiments were conducted in a batch system: in Stage A, the initial contaminant concentration (60, 80, and 100 mg/L) was varied while time, voltage, and electrode spacing were kept constant; in Stage B, one concentration was maintained and the treatment time was increased to investigate the optimal operating period. To evaluate efficiency, residual pharmaceutical concentrations were determined using UV-Vis spectrophotometry, and the total operational cost was estimated based on energy consumption and electrode wear. The assays showed that the highest removal efficiency, up to 46.7%, was achieved at an initial concentration of 60 mg/L. Increasing the exposure time did not necessarily result in higher efficiency, revealing the existence of an optimal operating period for each condition. Moreover, energy consumption and electrode wear increased with treatment time but were not directly related to removal efficiency. In conclusion, the study demonstrates the potential of electrocoagulation for the removal of pharmaceuticals from aqueous solutions, highlighting the importance of defining operational parameters to maximize process efficiency and economic feasibility in future applications.