SciELO - Scientific Electronic Library Online

 
vol.34 número1EVALUATION OF LIMESTONE IMPURITIES IN THE DESULFURIZATION PROCESS OF COAL COMBUSTION GASAN ALTERNATIVE ROUTE TO PRODUCE STANDARDS FOR GEL PERMEATION CHROMATOGRAPHY USING NITROXIDE MEDIATED POLYMERIZATION índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados

Journal

Artigo

Indicadores

Links relacionados

Compartilhar


Brazilian Journal of Chemical Engineering

versão impressa ISSN 0104-6632versão On-line ISSN 1678-4383

Resumo

BALSAMO, M.; ERTO, A.  e  LANCIA, A.. CHEMICAL DEMULSIFICATION OF MODEL WATER-IN-OIL EMULSIONS WITH LOW WATER CONTENT BY MEANS OF IONIC LIQUIDS. Braz. J. Chem. Eng. [online]. 2017, vol.34, n.1, pp.273-282. ISSN 0104-6632.  http://dx.doi.org/10.1590/0104-6632.20170341s20150583.

The demulsification of model water-in-oil (w/o) emulsions containing 1% wt. water by [Omim][PF6] and Aliquat® 336 ionic liquids (IL) as demulsifiers was investigated in batch mode at different temperatures (30, 45 and 60 °C) and demulsifier concentrations (2.5×10‒3, 1.2×10‒2 and 2.9×10‒2 mol L‒1). The model oil is a mixture n-heptane/toluene (70/30% wt.) with 1% wt. of Span® 83 as a surfactant. Experimental results showed that the main differences in demulsification dynamics between systems containing IL and blank (i.e., in the absence of demulsifier) are detected at 30 °C and for short demulsification times (t≤4 h). In particular, the demulsification efficiency is 8, 21 and 74% for the blank sample, [Omim][PF6] and Aliquat® 336 tested under the more concentrated IL condition, respectively. The superior demulsification performances of Aliquat® 336 with respect to [Omim][PF6] were related to the greater molecular weight and more hydrophobic character of its cation, likely able to induce a faster desorption of the surfactant at the w/o interface and consequently promoting water droplet coalescence. Moreover, the kinetic demulsification data were successfully interpreted by an empirical pseudo-first order model. In general, the obtained outcomes encourage future research efforts in the use of ionic liquids for the removal of low water fractions from w/o emulsions.

Palavras-chave : Model water-in-oil emulsions; Ionic liquids; Demulsifiers; Demulsification kinetic.

        · texto em Inglês     · Inglês ( pdf )