Journal ArticleDOI
Water in supercritical carbon dioxide microemulsions : spectroscopic investigation of a new environment for aqueous inorganic chemistry
TLDR
In this article, the formation of water in supercritical carbon dioxide (scCO2) microemulsions stabilized by an ammonium carboxylate perfluoro polyether (PFPE) surfactant was investigated.Abstract:
In this paper, we present spectroscopic evidence for the formation of water in supercritical carbon dioxide (scCO2) microemulsions stabilized by an ammonium carboxylate perfluoro polyether (PFPE) surfactant. FTIR spectroscopy has been employed to determine the existence of “bulk” (hydrogen-bonded) water (H2O and D2O) at the core of the microemulsions, and to distinguish between this and the presence of “free” (monomeric) water dissolved in the scCO2 and builds on preliminary results described elsewhere (Johnston, K. P.; Harrison, K. L.; Clarke, M. J.; Howdle, S. M.; Heitz, M. P.; Bright, F. V.; Carlier, C.; Randolph, T. W. Science 1996, 271, 624). Cloud point studies confirm that optically transparent and thermodynamically stable microemulsion solutions are formed. We have investigated the utility of these microemulsions as novel environments for reaction chemistry. In particular, we have shown that, using the PFPE surfactant, an aqueous solution of potassium permanganate (KMnO4) may be dispersed in scCO2...read more
Citations
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Journal ArticleDOI
Polymer synthesis and processing using supercritical carbon dioxide
TL;DR: Carbon dioxide is a clean and versatile solvent for the synthesis and processing of a range of materials as discussed by the authors, with particular attention being given to the formation of polymers with well defined morphologies.
Journal ArticleDOI
Homogeneous Catalysis in Supercritical Fluids.
TL;DR: Homogeneous molecular catalysts, which have far greater control over selectivity than heterogeneous solid catalysts are now being tested in SCFs, and early results show that high rates, improved selectivity, and elimination of masstransfer problems can be achieved.
Journal ArticleDOI
New Directions in Inorganic and Metal-Organic Coordination Chemistry in Supercritical Fluids
Jawwad A. Darr,Martyn Poliakoff +1 more
Journal ArticleDOI
Interactions of small molecules with reverse micelles
TL;DR: The methodologies that can be employed to obtain distribution constants, and literature data obtained in reverse micelles systems are described, and the effects promoted by solute incorporation on micellar properties are discussed.
Journal ArticleDOI
Synthesizing and Dispersing Silver Nanoparticles in a Water-in-Supercritical Carbon Dioxide Microemulsion.
TL;DR: A method to synthesize and stabilize metallic silver nanoparticles having diameters from 5 to 15 nm in supercritical CO{sub 2} using an optically transparent, water-in-CO{ sub 2} microemulsion is described.
References
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Journal ArticleDOI
Reverse micelles as microreactors
TL;DR: In this article, it is shown that reverse micelles can be used as microreactors to produce either well-defined nanosized crystallites or chemically modified enzymes, and some prospective aspects of the use of such water-in-oil droplets are discussed.
Journal ArticleDOI
Synthesis of Fluoropolymers in Supercritical Carbon Dioxide
TL;DR: The homogeneous solution polymerization of highly fluorinated acrylic monomers can be achieved in supercritical carbon dioxide by using free radical methods and detailed decomposition rates and efficiency factors were measured for azobisisobutyronitrile in super critical carbon dioxide and were compared to those obtained with conventional liquid solvents.
Journal ArticleDOI
Homogeneous catalytic hydrogenation of supercritical carbon dioxide
TL;DR: The use of a supercritical phase, in which hydrogen is highly miscible, leads to a very high initial rate of reaction up to 1,400 moles of formic acid per mole of catalyst per hour as discussed by the authors.
Journal ArticleDOI
Synthesis of copper metallic clusters using reverse micelles as microreactors
I. Lisiecki,M. P. Pileni +1 more
TL;DR: In this paper, reverse micelles were used to synthesize in situ nanometallic copper particles, and the size of the metallic cluster increases from 2 to 10 nm with increasing water content.
Journal ArticleDOI
The kinetics of solubilisate exchange between water droplets of a water-in-oil microemulsion
TL;DR: Exchange rates of aqueous solubilisates between water droplets in a water-in-oil microemulsion stabilised by sodium bis(2-ethyl-hexyl) sulphosuccinate (AOT) have been measured as a function of droplet size, temperature and the chain length of the oil as mentioned in this paper.
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