Eficiência de sistemas microemulsionados no tratamento de areia de praia contaminada com petróleo

Abstract

The growth in world energy demand for oil has provided an increase in its exploration, production and transportation in onshore or offshore environments. However, during the performance of these activities, oil spills may occur due to leaks, corrosion of the pipes, blow-outs, among others. Oil spills contaminate the environment, affecting soil, surface water and beach sands. The remediation of contaminated sediments, such as sand and soil, is a complex task since the oil adsorbed on the surface of the grains is difficult to remove. The remediation of contaminated sediments can be carried out by physical, chemical, biological methods or by a combination of these methods. Among the methods applied to treat contaminated sediments, the use of microemulsified systems has stood out. Laboratory-scale results have shown significant results in terms of removal efficiency, reduction in the amount of surfactant and the use of biodegradable surfactants. The present work analyzed a microemulsified system with unprecedented characteristics, with a surfactant of vegetable origin (coconut soap), butanol as a surfactant, distilled water as an aqueous phase and n-hexane as an oily phase in the remediation of oil-contaminated beach sand. The investigation on optimal microemulsion composition was carried out based on experimental mixture planning, and once determined, the optimal composition had its effects evaluated experimentally. The results showed that increases in the mass of the applied microemulsion provided increases in the percentage of oil removed. The contact time factor was also evaluated, and the results showed that this factor does not influence the percentage of oil removed. According to the results, the minimum and maximum percentages of oil removed observed were 8.96 and 58.07%, respectively.