Breaking Oil-in-water Emulsions Stabilized By Yeast

dc.creatorFurtado
dc.creatorGuilherme F.; Picone
dc.creatorCarolina S. F.; Cuellar
dc.creatorMaria C.; Cunha
dc.creatorRosiane L.
dc.date2015-APR
dc.date2016-06-07T13:33:39Z
dc.date2016-06-07T13:33:39Z
dc.date.accessioned2018-03-29T01:49:24Z
dc.date.available2018-03-29T01:49:24Z
dc.identifier
dc.identifierBreaking Oil-in-water Emulsions Stabilized By Yeast. Elsevier Science Bv, v. 128, p. 568-576 APR-2015.
dc.identifier0927-7765
dc.identifierWOS:000353930000071
dc.identifier10.1016/j.colsurfb.2015.03.010
dc.identifierhttp://www.sciencedirect.com/science/article/pii/S0927776515001447
dc.identifierhttp://repositorio.unicamp.br/jspui/handle/REPOSIP/243757
dc.identifier.urihttp://repositorioslatinoamericanos.uchile.cl/handle/2250/1307455
dc.descriptionSeveral biotechnological processes can show an undesirable formation of emulsions making difficult phase separation and product recovery. The breakup of oil-in-water emulsions stabilized by yeast was studied using different physical and chemical methods. These emulsions were composed by deionized water, hexadecane and commercial yeast (Saccharomyces cerevisiae). The stability of the emulsions was evaluated varying the yeast concentration from 7.47 to 22.11% (w/w) and the phases obtained after gravity separation were evaluated on chemical composition, droplet size distribution, rheological behavior and optical microscopy. The cream phase showed kinetic stability attributed to mechanisms as electrostatic repulsion between the droplets, a possible Pickering-type stabilization and the viscoelastic properties of the concentrated emulsion. Oil recovery from cream phase was performed using gravity separation, centrifugation, heating and addition of demulsifier agents (alcohols and magnetic nanoparticles). Long centrifugation time and high centrifugal forces (2 h/150,000 x g) were necessary to obtain a complete oil recovery. The heat treatment (60 degrees C) was not enough to promote a satisfactory oil separation. Addition of alcohols followed by centrifugation enhanced oil recovery: butanol addition allowed almost complete phase separation of the emulsion while ethanol addition resulted in 84% of oil recovery. Implementation of this method, however, would require additional steps for solvent separation. Addition of charged magnetic nanoparticles was effective by interacting electrostatically with the interface, resulting in emulsion destabilization under a magnetic field. This method reached almost 96% of oil recovery and it was potentially advantageous since no additional steps might be necessary for further purifying the recovered oil. (C) 2015 Elsevier B.V. All rights reserved.
dc.description128
dc.description
dc.description
dc.description568
dc.description576
dc.descriptionFundacao de Amparo Pesquisa e Desenvolvimento de Sao Paulo-Brazil [2011/51707-1, 2012/14003-9]
dc.descriptionConselho Nacional de Desenvolvimento Cientfiico e Tecnologico-Brazil [305477/2012-9, 130752/2012-6]
dc.description
dc.description
dc.description
dc.languageen
dc.publisherELSEVIER SCIENCE BV
dc.publisher
dc.publisherAMSTERDAM
dc.relationCOLLOIDS AND SURFACES B-BIOINTERFACES
dc.rightsembargo
dc.sourceWOS
dc.subjectSaccharomyces-cerevisiae
dc.subjectBiodiesel Production
dc.subjectSolid Particles
dc.subjectRecent Trends
dc.subjectSurface
dc.subjectCells
dc.subjectDemulsification
dc.subjectEmulsification
dc.subjectBioemulsifier
dc.subjectChallenges
dc.titleBreaking Oil-in-water Emulsions Stabilized By Yeast
dc.typeArtículos de revistas


Este ítem pertenece a la siguiente institución