Extração líquido-líquido no tratamento de efluentes da indústria de petróleo utilizando microemulsões

Abstract

In the current scenario, liquid-liquid extraction has gained considerable relevance in the realm of studies and applications in the oil industry due to its notable efficiency in separating fluids of various interests. This is reflected, for example, in the use of microemulsions for the treatment of produced water, which is one of the most abundant wastes in the petroleum industry. Due to its formation, this effluent contains a complex mixture of organic and inorganic compounds, making its disposal/reuse unfeasible without prior treatment. Therefore, the present study aimed to investigate the feasibility of applying this extraction method in synthetic produced water, using microemulsions as extracting agents. The system was evaluated on a laboratory scale to analyze its behavior and examine associated operational variables. For this purpose, the preparation and characterization of selected microemulsified systems were carried out. These systems consisted of two microemulsions containing SFC (saponified coconut oil) or commercial coconut soap as a surfactant, butanol as a co-surfactant, hexane as an organic phase, and synthetic produced water as an aqueous phase, in the proportion of 17.5% S/C, 7.5% organic phase, and 75% aqueous phase, with S/C=4. A study of the inherent variables in the process was also conducted, considering different system configurations From this, it was possible to obtain a significant reduction in Oil and Grease Content (OCG) in produced water. The use of saponified coconut oil (SFC) reduced OGC by 72%, while commercial coconut soap reduced it by 90%. These results indicated the effectiveness of the treatment in removing oil from produced water, highlighting the potential of these microemulsified systems as a promising approach for industrial-scale oil extraction.