Dantas, Tereza Neuma de CastroSilva, Dennys Correia da2021-05-102021-05-102021-03-15SILVA, Dennys Correia da. Floculação iônica e extração líquido-líquido utilizando tensoativos e sistemas microemulsionados para remoção de óleo de água produzida. 2021. 176f. Tese (Doutorado em Engenharia Química) - Centro de Tecnologia, Universidade Federal do Rio Grande do Norte, Natal, 2021.https://repositorio.ufrn.br/handle/123456789/32480The produced water is one of the main sources of pollution derived from the oil industry and represents one of the most important environmental concerns. In this work, surfactants and microemulsion systems were used to remove the oil dispersed in the produced water by ion flocculation and liquid-liquid extraction methods. Ionic flocculation has been suggested as an alternative for removing oil from the produced water by using an ionic surfactant of saponified coconut oil (SBCO) as part of the capture of oil by micellar solubilization, followed by ionic flocculation by Ca2+ ions. A factorial experimental design was applied in order to optimize the oil removal process. The experiments investigated the influence of the surfactant concentration plus calcium chloride (C), temperature (T), and stirring speed (v), obtaining oil removal efficiency (RE) = 91.49%. Subsequently, the influence of pH and CaCl2/surfactant ratio on the higher RE system was evaluated, obtaining RE = 99.98% in pH > 10, and CaCl2/surfactant ratio = 1. Then, the system which showed greater oil removal by using microemulsion as flocculants and SBCO as a surfactant was reproduced, presenting RE = 99.98 %. Thus, one can conclude that the application of ionic flocculation using OCBS is an efficient technique in the treatment of the produced water to remove oil. In experiments involving liquid-liquid extraction, the microemulsion systems used were composed of produced water as an aqueous phase; aviation kerosene as an oily phase; isoamyl alcohol and 1-butanol as co-surfactants; and Dissolvan® and Lipesa® as surfactants. An experimental design was applied to optimize the process, and the experiments were carried out according to the Scheffé network, showing oil removal efficiencies (RE) between 24-99%. The microemulsion extraction point used to optimize the process was composed of 60% by weight of produced water, 5% by weight of kerosene, and 35% by weight of the co-surfactant/surfactant ratio (ratio C/S = 9). The effects of the C/S ratio, microemulsion load capacity, temperature, and phase separation speed were evaluated. From these tests, it was possible to obtain 99.98% oil removal using C/S = 9 and T = 50–60 ° C, demonstrating the viability of the evaluated systems. Comparing both techniques, it was possible to verify that the ionic flocculation presented a greater advantage, thus it used fewer amounts of reagents, and it had higher percentages of oil removal. However, the microemulsion extraction was also very efficient, and it has also the advantage of extract some metals from the produced water.Acesso AbertoÁgua produzidaTensoativosMicroemulsõesFloculação iônicaExtração líquido-líquidodoctoralThesis