Layer-by-layer encapsulated nano-emulsion of ionic liquid loaded with functional material for extraction of Cd(2+) ions from aqueous solutions
File(s)
Accepted version
Author(s)
Elizarova, IS
Luckham, PF
Type
Journal Article
Abstract
Ionic liquids can serve as an environmentally-friendly replacement for solvents in emulsions, therefore they are considered suitable to be used as an emulsified medium for various active materials one of which are extractors of metal ions. Increasing the extraction efficiency is considered to be one of the key objectives when working with such extraction systems. One way to improve the extraction efficiency is to increase the contact area between the extractant and the working ionic solution. This can be accomplished by creating a nano-emulsion of ionic liquid containing such an extractant. Since emulsification of ionic liquid is not always possible in the sample itself, there is a necessity of creating a stable emulsion that can be added externally and on demand to samples from which metal ions need to be extracted. We propose a method of fabrication of a highly-stable extractant-loaded ionic liquid-in-water nano-emulsion via a low-energy phase reversal emulsification followed by continuous layer-by-layer polyelectrolyte deposition process to encapsulate the nano-emulsion and enhance the emulsion stability. Such a multilayered stabilized nano-emulsion was tested for extraction of Cd(2+) and Ca(2+) ions in order to determine its extraction efficiency and selectivity. It was found to be effective in the extraction of Cd(2+) ions with near 100% cadmium removal, as well as being selective since no Ca(2+) ions were extracted. The encapsulated emulsion was removed from samples post-extraction using two methods - filtration and magnetic separation, both of which were shown to be viable under different circumstances - larger and mechanically stronger capsules could be removed by filtration, however magnetic separation worked better for both smaller and bigger capsules. The long-term stability of nano-emulsion was also tested being a very important characteristic for its proposed use: it was found to be highly stable after four months of storage time.
Date Issued
2017-04-01
Date Acceptance
2016-12-22
Citation
Journal of Colloid and Interface Science, 2017, 491 (1), pp.286-293
ISSN
0021-9797
Publisher
Elsevier
Start Page
286
End Page
293
Journal / Book Title
Journal of Colloid and Interface Science
Volume
491
Issue
1
Copyright Statement
© 2016 Elsevier Inc. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Identifier
http://www.ncbi.nlm.nih.gov/pubmed/28049053
PII: S0021-9797(16)31053-0
Subjects
Science & Technology
Physical Sciences
Chemistry, Physical
Chemistry
Ionic liquid
Layer-by-layer
Polyelectrolyte
Encapsulation
Emulsification
Low-energy emulsification phase inversion
Self-assembly
Separation
Nano-capsules
Nano-emulsion
Magnetite
Trihexyl(tetradecyl)phosphonium-bis(tri fluoromethylsulfonyl)imide
[P-14666][Tf2N]
1-(2-Pyridylazo)-2-naphthol
ATOMIC-ABSORPTION-SPECTROMETRY
CATIONIC BIPOLAR AMPHIPHILES
ULTRATHIN MULTILAYER FILMS
SELF-ASSEMBLY PROCESS
POLYELECTROLYTE ADSORPTION
CONSECUTIVE ADSORPTION
PHASE MICROEXTRACTION
MICROEMULSIONS
STABILITY
CADMIUM
1-(2-Pyridylazo)-2-naphthol
Emulsification
Encapsulation
Ionic liquid
Layer-by-layer
Low-energy emulsification phase inversion
Magnetite
Nano-capsules
Nano-emulsion
Polyelectrolyte
Self-assembly
Separation
Trihexyl(tetradecyl)phosphonium-bis(trifluoromethylsulfonyl)imide
[P(14666)][Tf(2)N]
Chemical Physics
02 Physical Sciences
03 Chemical Sciences
09 Engineering
Publication Status
Published
Coverage Spatial
United States
Date Publish Online
2016-12-24