Supercritical Fluids: Properties and Applications

Abstract

Currently, both humanity and the whole planet are living in a critical time, which leads us to look for more sustainable formulas to interact with the environment. One of the important changes in the design and operation of chemical processes is the search for environmentally friendly technologies. Many industrial processes are carried out under severe conditions or with reactants that involve the use of strong acids, toxic metal catalysts, organic solvents, and processes at high temperatures and/or pressures. Supercritical fluids (SCFs) and, among these, supercritical carbon dioxide (scCO2), have been revealed as promising environmentally friendly solvents, energy-efficient, selective, and capable of reducing waste, constituting an alternative to conventional organic solvents. The use of SCF, such as solvents and reaction media, makes it possible to work in less severe and more environmentally friendly conditions, even considerably increasing the efficiency of the processes. This chapter provides a brief review of the most important properties of SCF, with special emphasis on scCO2, as well as some of the most important applications.

Lipid-based nanoparticles as drug delivery carriers for cancer therapy

“…Carbon dioxide is the most commonly utilized SCF because of its outstanding safety and affordable price. The most common method for producing LBNPs with SCF involves altering the ambient pressure of supercritical CO 2 (scCO 2 ) ( 106 ). In a nutshell, scCO 2 is utilized as a solvent, and when fed into a high-pressure vessel, the solubilities of solid lipids and medications in scCO 2 are boosted.…”

Enhanced Oil Recovery Using Polymer Alternating CO2 Gas Injection: Mechanisms, Efficiency, and Environmental Benefits

“…Also, when the reservoir pressure and temperature exceed the critical temperature (31.1 °C) and critical pressure (7.39 MPa) of CO 2 , CO 2 attains a supercritical state within in situ reservoir conditions . Supercritical CO 2 (sc.CO 2 ) has unique physiochemical properties where its density is close to water, viscosity is close to gas, and has a relatively higher diffusion coefficient . Numerous studies have been reported on CO 2 -EOR methods, including continuous gas injection, water-alternating gas (WAG) injection, tapered WAG, carbonated water injection (CWI), CO 2 huff-n-puff, and CO 2 foam flooding. − However, there are challenges associated with every CO 2 -EOR project.…”

Carotenoids and Fatty Acids Obtained from Paprika Capsicum annuum by Supercritical Carbon Dioxide and Ethanol as Co-Extractant

“…Supercritical carbon dioxide (SC-CO 2 ) extraction has been developed for over forty years. The process is applied in research as well as for industrial purposes [ 23 ]. On a large industrial scale, typical applications are the extraction of hop components, decaffeination of tea and coffee, and the separation of lecithin from oil [ 24 ].…”