Uso de diferentes oxidantes para remediação de solo contaminado com óleo queimado

Abstract

This study evaluated the use of different advanced oxidation processes (AOPs) for the remediation of soil contaminated with waste lubricating oil, focusing on the comparison between distinct oxidizing systems. Soil contamination by petroleum-derived residues is a significant environmental issue due to the high toxicity, persistence, and bioaccumulation potential of hydrocarbons. In this context, the objective was to analyze the performance of hydrogen peroxide (H₂O₂), Fenton’s reagent, and the combined system of hydrogen peroxide and persulfate, with the possible use of goethite as an activator. The experiments were conducted using an artificial sandy soil contaminated with a high concentration of waste oil, allowing a comparative evaluation under controlled conditions. Treated samples were analyzed for total petroleum hydrocarbons (TPH) using gas chromatography to quantify contaminant reduction. The results showed that the combined hydrogen peroxide and persulfate system achieved the highest efficiency, with approximately 32% TPH reduction, whereas hydrogen peroxide alone and Fenton’s reagent resulted in reductions of about 21% and 22%, respectively. It was also observed that the oxidation processes were more effective in degrading lighter hydrocarbon fractions, with limitations in removing heavier compounds associated with unresolved complex mixtures (UCM). It can be concluded that AOPs present potential for soil remediation applications, particularly when combined systems are employed; however, their efficiency strongly depends on operational conditions such as oxidant-to-contaminant ratio and soil characteristics.