Chemical reactions in supercritical fluids

Synthetic, Mechanistic, and Supercritical Applications Edited by Rudi van Eldik and Frank-Gerrit KIdrner 

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The several theoretical and/or simulation methods developed for modelling the solvation phenomena can be applied to the treatment of solvent effects on chemical reactivity. A variety of systems - ranging from small molecules to very large ones, such as biomolecules [236-238], biological membranes [239] and polymers [240] -and problems - mechanism of organic reactions [25, 79, 223, 241-247], chemical reactions in supercritical fluids [216, 248-250], ultrafast spectroscopy [251-255], electrochemical processes [256, 257], proton transfer [74, 75, 231], electron transfer [76, 77, 104, 258-261], charge transfer reactions and complexes [262-264], molecular and ionic spectra and excited states [24, 265-268], solvent-induced polarizability [221, 269], reaction dynamics [28, 78, 270-276], isomerization [110, 277-279], tautomeric equilibrium [280-282], conformational changes [283], dissociation reactions [199, 200, 227], stability [284] - have been treated by these techniques. Some of these... 

T. Clifford, K. Bartle, Chemical Reactions in Supercritical Fluids , Chem. Ind. 1996, 449-452. 

Supercritical fluids, particularly supercritical C02, scC02, are attractive solvents for cleaner chemical synthesis. However, optimisation of chemical reactions in supercritical fluids is more complicated than in conventional solvents because the high compressibility of the fluids means that solvent density is an additional degree of freedom in the optimisation process. Our overall aim is to combine spectroscopy with chemistry so that processes as varied as analytical separations and chemical reactions can be monitored and optimised in real time. The approach is illustrated by a brief discussion of three examples (i) polymerisation in scC02 (ii) hydrogen and hydrogenation and (iii) miniature flow reactors for synthetic chemistry. 

Supercritical chemistry a review of chemical reactions in supercritical fluids solutions [63]... 

Poliakoff, M. Howdle, S.M. Supercritical chemistry a review of chemical reactions in supercritical fluids solutions. In Third International Symposium on Supercritical Fluids, International Society for the Advancement of Supercritical Fluids Nottingham, UK, 1999. 

Poliakoff, M. George, M.W. Howdle, S.M. Inorganic and related chemical reactions in supercritical fluids. In Chemistry under Extreme or Non-Classical Conditions van Eldik, R., Hubbard, D.C., Eds. Wiley New York, 1997 189-218. 

Chemical reactions in supercritical fluids (SCF) have been extensively studied during the past 30 years. Although many of these studies have been performed on a small scale (<60 mL), recent developments tend to attain the liter scale in order to gain engineering as well as chemical and physical information. To carry out chemical reactions on an industrial scale requires a detailed and comprehensive understanding of the energetics of exothermic reactions. The development of an intrinsically safe process requires data on kinetics, physicochemical properties, thermicity, and safety aspects [1],... 

T Clifford, K Bartle. Chemical reactions in supercritical fluids. Chem Ind (London) 1996(12) 449 52, 1996. 

JR Combes, KP Johnston, KE O Shea, MA Fox. Influence of solvent-solute and solute-solute clustering on chemical reactions in supercritical fluids. In FV Bright, MEP McNally, eds. Supercritical Fluid Technology Theoretical and Applied Approaches to Analytical Chemistry. ACS Symposium Series No. 488. Washington, D.C. American Chemical Society, 1992, pp 31 7. 

T Ikariya, PG Jessop, R Noyori. Chemical reactions in supercritical fluids. Yuki Gosei Kagaku Kyokaishi 53(5) 358-369, 1995. 

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