CHAPTER 10: Supercritical Solvents
Published:20 Oct 2021
The present chapter overviews the uses of supercritical fluids (SFCs) as solvents for different applications, including extraction technologies and chemical synthesis. For the reader's convenience, an introductory section describes the general features of most popular SCFs with a focus on supercritical CO2 and water, and comments on the major laboratory and industrial processes with SCFs, including solid and liquid extractions, polymer synthesis, processing and purification, drying/cleaning, and energy uses. Thereafter, a second section is devoted to selected applications of supercritical solvents in organic synthesis with emphasis on transformations of general interest to green chemistry. In particular, the metathesis of alkenes in scCO2, glucose conversion in scH2O, biodiesel production in supercritical light alcohols (methanol and ethanol), and the esterification of levulinic acid in scCO2 are illustrated. For the latter example, a comparative (SCF vs. conventional) green metrics evaluation is also performed.