Avaliação da degradação da oxitetraciclina em água, usando fotocatálise heterogênea combinada com energia solar

Abstract

Pharmaceuticals are classified as emerging contaminants and when released without pre-treatment (directly), even in low concentrations, they tend to pose risks to human and animal health and the environment. Among the drugs with a high potential risk are antibiotics, including oxytetracycline (OTC). The presence of this drug in aquatic environments is a major concern, as it has great potential to cause adverse effects on human and animal health. It is therefore necessary to apply efficient methods to remove this type of pollutant from aqueous solutions. Advanced Oxidative Processes (AOPs) have been widely used to degrade these compounds. Among the AOPs are photocatalytic processes which, when applied correctly, can degrade these contaminants. Their application, combined with semiconductors, accelerates the degradation of complex contaminant structures. The aim of this study was to analyze 1the degradation of effluents containing oxytetracycline (OTC) using heterogeneous photocatalysis activated by titanium dioxide and assisted by solar ultraviolet (UV) radiation. The process was applied with and without oxygenation. OTC was quantified during and after the process using the colorimetric method. The influence of pH in the reaction medium, TiO2 catalyst loading, and initial OTC concentration were evaluated. In the process carried out with oxygenation, 99% degradation of oxytetracycline was achieved in 60 minutes. However, without oxygenation, degradation was 84% in 90 minutes. In both cases, with and without oxygenation, the results showed great potential for the degradation of oxytetracycline, thus contributing as a viable treatment for effluents containing this contaminant.