Abstract
Cagniard de la Tour showed in 1822 that there is a critical temperature above which a single substance can only exist as a fluid and not as either a liquid or gas. He heated substances, present as both liquid and vapor, in a sealed cannon, which he rocked back and forth and discovered that, at a certain temperature, the splashing ceased. Later, he constructed a glass apparatus in which the phenomenon could be more directly observed. These phenomena can be put into context by reference to Fig. 1, which is a phase diagram of a single substance. The diagram is schematic, the pressure axis is nonlinear, and the solid phase at high temperatures occurs at very high pressures. Further solid phases and also liquid crystal phases can also occur on a phase diagram. The areas where the substance exists as a single solid, liquid, or gas phase are labeled, as is the triple point where the three phases coexist. The curves represent coexistence between two of the phases. If we move upward along the gas-liquid coexistence curve, which is a plot of vapor pressure vs temperature, both temperature and pressure increase. The liquid becomes less dense because of thermal expansion, and the gas becomes more dense as the pressure rises. At the critical point, the densities of the two phases become identical, the distinction between the gas and the liquid disappears, and the curve comes to an end at the critical point. The substance is now described as a fluid. The critical point has pressure and temperature co-ordinates on the phase diagram, which are referred to as the critical temperature, T c, and the critical pressure, p c, and which have particular values for particular substances, as shown by example in Table 1 (1).
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsReferences
Reid R. C., Prausnitz J. M., and Poling B. E. (1986) The Properties of Gases and Liquids. McGraw-Hill New York.
Modell M. (1982) Processing methods for the oxidation of organics in supercritical water. U.S. Patent 4, 338, 199.
Howdle S. M., Healy M. A., and Poliakoff M. (1990) Organometallic chemistry in supercritical fluids: the generation and detection of dinitrogen and non-classical dihydrogen complexes of group 6, 7 and 8 transition metals at room temperature. J. Am. Chem. Soc. 112, 4804–4813.
McHugh M. A. and Krukonis V. J. (1994) Supercritical Fluid Extraction, 2nd ed., Butterworth-Heinemann Boston.
Span R. and Wagner W. (1996) A new equation of state for carbon dioxide covering the fluid region from the triple-point temperature to 1100 K at pressures up to 800 MPa. J. Phys. Chem. Ref. Data 25, 1509–1596.
Vesovic V., Wakeham W. A., Olchowy G. A., Sengers J. V., Watson J. T. R., and Millat J. (1990) The transport properties of carbon dioxide. J. Phys. Chem. Ref. Data 19, 763–808.
Clifford A. A. and Coleby S. E. (1991) Diffusion of a solute in dilute solution in a supercritical fluid. Proc. R. Soc. Lond. A433, 63–79.
Bartle K. D., Baulch D. L., Clifford A. A., and Coleby S. E. (1991) Magnitude of the diffusion coefficient anomaly in the critical region and its effect on supercritical fluid chromatography. J. Chromatogr. 557, 69–83.
Page S. H., Sumpter S. R., and Lee M. L. (1992) Fluid phase equilibria in supercritical fluid chromatography with CO2-based mixed mobile phases: a review. J. Microcol. Sep. 4, 91–122.
Bartle K. D., Clifford A. A., Jafar S. A., and Shilstone G. F. (1991) Solubilities of solids and liquids of low volatility in supercritical carbon dioxide. J. Phys. Chem. Ref. Data 20, 713–756.
Heikes D. L. (1994) SFE with GC and MS determination of safrole and related allylbenzenes in sassafras teas. J. Chromatogr. Sci. 32, 253–258.
Janda V., Bartle K. D., and Clifford A. A. (1993) Supercritical fluid extraction in environmental analysis. J. Chromatog.A 642, 283–299.
Barnabas I. J., Dean J. R., and Owen S. P. (1994) Supercritical fluid extraction of analytes from environmental samples: a review. Analyst 119, 2381–2394.
Smith R. M. (1996) Supercritical fluid extraction of natural products. LC-GC Intl. 9, 8–15.
Um K. W., Bailey M. E., Clarke A. D., and Chao R. R. (1992) Concentration and identification of volatile compounds from heated beef fat using supercritical CO2 extraction-gas liquid chromatography/mass spectrometry. J. Agric. Food Chem. 40, 1641–1646.
Cirimele V., Kintz P., Majdalani R., and Mangin P. (1995) Supercritical fluid extraction of drugs in drug addict hair. J. Chromatog.B 673, 173–181.
Lin B. Y. and Wai C. M. (1994) Supercritical fluid extraction of lanthanides with fluorinated β-diketones and tributyl phosphate. Anal. Chem. 66, 1971–1975.
Via J. C., Braue C. L., and Taylor L. T. (1994) Supercritical fluid fractionation of a low molecular weight, high-density polyethylene wax using carbon dioxide, propane, and propane-modified carbon dioxide. Anal. Chem. 66, 603–609.
Hunt T. P., Dowle C. J., and Greenway G. (1991) Analysis of poly(vinyl chloride) additives by supercritical fluid extraction and supercritical fluid chromatography. Analyst 116, 1299–1304.
Sangün M. K. (1998) Selective supercritical fluid extraction from plant materials. Ph.D. thesis. School of Chemistry Leeds University, UK.
Sato M., Goto M., Kodama A., and Hirose T. (1997) Supercritical fluid extraction with reflux for citrus oil processing. ACS Symp. Ser. 670, 119–131.
Cross R. F., Ezzell J. L., and Richter B. E. (1993) The supercritical fluid extraction of polar drugs (sulfonamides) from inert matrices and meat animal products.J. Chromatogr. Sci. 31, 162–169.
Luque de Castro M. D. and Tena M. T. (1996) Strategies for supercritical fluid extraction of polar and ionic compounds. Trends Anal. Chem. 15, 32–37.
Ashraf-Khorassani M., Combs M. T., Taylor L. T., Willis J., Liu X. J., and Frey C. R. (1997) Separation and identification of sulfonamide drugs via SFC/FT-IR mobile phase elimination interface. App. Spectros. 51, 1791–1795.
Taylor L. T. (1997) Trends in supercritical fluid chromatography: 1997. J. Chromatogr. Sci. 35, 374–382.
Bartle K. D., Bevan C. D., Clifford A. A., Jafar S. A., Malak N., and Verrall M. S. (1995) Preparative-scale supercritical fluid chromatography.J. Chromatogr.A 697, 579–585.
Nomura A., Yamada J., Takatsu A., Horimoto Y., and Yarita T. (1993)Supercritical fluid chromatographic determination of cholesterol and cholesteryl esters in serum on ODS-silica gel column. Anal. Chem. 65, 1994–1997.
Bartle K. D., Boddington T., Clifford A. A., and Cotton N. J. (1991) Supercritical fluid extraction and chromatography for the determination of oligomers in poly(ethylene terephthalate) films. Anal. Chem. 63, 2371–2377.
Scalia S. and Games D. E. (1993) Determination of free bile acids in pharmaceutical preparations by packed column supercritical fluid chromatography. J. Pharm. Sci. 82, 44–47.
Villette V., Herbreteau B., Lafosse M., and Dreux M. (1996) Free bile acid analysis by supercritical fluid chromatography and evaporative light scattering detection. J. Liq. Chrom. Rel. Technol. 19, 1805–1818.
Morgan E. D., Murphy S. J., Games D. E., and Mylchreest I. C. (1988) Analysis of ecdysteroids by supercritical fluid chromatography.J. Chromatogr. 441, 165–169.
Huang H. P. and Morgan E. D. (1990) Analysis of azadirachtin by supercritical fluid chromatography.J. Chromatogr. 519, 137–143.
Roberts D. W., Wilson I. D., and Reid E. (1990) Methodol. Surv. Biochem. Anal. 20, 257.
Mazzotti M., Storti G., and Morbidelli M. (1997) Supercritical fluid simulated moving bed chromatography. J. Chromatogr.A 786, 309–320.
Fukuzato R. (1991) Supercritical fluid processing research and business activities in Japan In Proceedings of the second international symposium on supercritical fluids (McHugh M. A., ed.), John Hopkins University Press Baltimore, p. 196.
Wai C. M. and Wang S. F. (1997) Supercritical fluid extraction: metals as complexes. J. Chromatogr.A 785, 369–383.
Ekhtera M. R., Mansoori G. A., Mensinger M. C., Rehmat A., and Deville B.(1997) Supercritical fluid extraction for remediation of contaminated soil. ACS Symp.Ser. 670, 208–231.
Mitton D. B., Han E. H., Zhang S. H., Hautanen K. E., and Latanisian R. M. (1997) Degradation in supercritical water oxidation systems. ACS Symp. Ser. 670, 242–254.
Donohue M. D., Geiger J. L., Kiamos A. A., and Nielsen K. A. (1996) Reduction of volatile organic compound emissions during spray painting: a new process using supercritical carbon dioxide to replace traditional paint solvents. ACS Symp.Ser. 626, 152–167.
Özcan A. S., Clifford A. A., and Bartle K. D. (1998) Dyeing of cotton fibres with disperse dyes in supercritical carbon dioxide. Dyes Pigments 36, 103–110.
Bakker G. L. and Hess D. W. (1998) Surface cleaning and carbonaceous film removal using high pressure, high temperature water and water/CO2 mixtures. J. Electrochem. Soc. 145, 284–291.
Cooney C. M. (1997) Supercritical CO2-based cleaning system among Green Chemistry Award winners. Environ. Sci. Tech. 31, A314–A315.
Smith R. M., ed. (1988) Supercritical Fluid Chromatography. The Royal Society of Chemistry London.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2000 Humana Press Inc.
About this protocol
Cite this protocol
Clifford, A.A., Williams, J.R. (2000). Introduction to Supercritical Fluids and Their Applications. In: Williams, J.R., Clifford, A.A. (eds) Supercritical Fluid Methods and Protocols. Methods In Biotechnology™, vol 13. Humana Press. https://doi.org/10.1385/1-59259-030-6:1
Download citation
DOI: https://doi.org/10.1385/1-59259-030-6:1
Publisher Name: Humana Press
Print ISBN: 978-0-89603-571-3
Online ISBN: 978-1-59259-030-8
eBook Packages: Springer Protocols