Melo, Keila Rejane de OliveiraDantas, Tereza Neuma de CastroMoura, Maria Carlenise Paiva de AlencarDantas Neto, Afonso AvelinoOliveira, Mônica RodriguesBarros Neto, Eduardo Lins2021-11-302021-11-302015DANTAS NETO, Afonso Avelino; BARROS NETO, Eduardo Lins; MELO, Keila Rejane de Oliveira; MOURA, Maria Carlenise Paiva de Alencar; DANTAS, Tereza Neuma de Castro; OLIVEIRA, Mônica Rodrigues. Chromium extraction by microemulsions in two-and three-phase systems. Brazilian Journal of Chemical Engineering (Impresso), v. 32, n. 4, p. 949 - 956, 2015. Disponível em: https://www.scielo.br/j/bjce/a/RcsFQ4DF6Crwd5JQSsBVNmz/?lang=en. Acesso em: 26 jul. 2021. DOI: https://doi.org/10.1590/0104-6632.20150324s000029850104-66321678-4383https://repositorio.ufrn.br/handle/123456789/45080Microemulsion systems were used to remove chromium from an aqueous solution obtained from acid digestion of tannery sludge. The systems were composed by: coconut oil soap as surfactant, 1-butanol as cosurfactant, kerosene as the oil phase, and chromium solution as the aqueous phase. Two- and three-phase microemulsion extraction methods were investigated in the experiments. Viscosity, effective diameter of the droplets, and extraction and re-extraction efficiencies were evaluated for each system. Two- and three-phase systems showed small variations in droplet diameter, which can be attributed to the formation of micellar structures. Chromium recovery efficiencies for the studied systems were over 96%. The re-extraction step showed that the stripping solution used can release more than 96% of the chromium from the microemulsion phase. Experimental results confirm that chromium can be recovered efficiently using microemulsion systemsAttribution 3.0 Brazilhttp://creativecommons.org/licenses/by/3.0/br/Tannery sludgeChromiumMicroemulsionCoconut oil soapWinsor systemChromium extraction by microemulsions in two- and three-phase systemsarticle