Superheated water offers alternative for plant extractions.Express Separations Ltd. (Unit 2A Brickyard Road, Roecliff, Boroughbridge, York YO51 9NS, England, U.K.) has launched a range of services based on the company's research into the use of superheated su·per·heat tr.v. su·per·heat·ed, su·per·heat·ing, su·per·heats 1. To heat excessively; overheat. 2. water as an extraction solvent and refining tool. Best-known for the use of carbon dioxide carbon dioxide, chemical compound, CO2, a colorless, odorless, tasteless gas that is about one and one-half times as dense as air under ordinary conditions of temperature and pressure. as a clean extraction medium, researchers at Express have demonstrated that superheated water extraction improves the selectivity of essential oils and plant materials. Furthermore, the energy requirements of this process are relatively small, which should reduce operating and capital costs significantly. Superheated water involves liquid water that is placed under pressure between 100 C and its critical temperature, 374 C. As its temperature rises, the structure of water changes dramatically. At optimum temperatures and pressures, superheated water behaves in ways similar to an organic solvent, and it can increase solubility. Improved solubility makes useful a range of extraction solutions to the food industry, particularly those concerned with the environmental impact of traditional organic solvents, such as methanol. Although particularly effective in extracting polar or polarizable po·lar·ize v. po·lar·ized, po·lar·iz·ing, po·lar·iz·es v.tr. 1. To induce polarization in; impart polarity to. 2. To cause to concentrate about two conflicting or contrasting positions. compounds, the technique is proving useful in recovering valuable components from materials, such as cereals, vegetables, fruit and oil-rich crops. In addition, work with plant extractions has uncovered a new route for essential oil deterpenation, since the different solubilities of terpenes terpenes (terˑ·pēnz), n.pl a large-sized group of unsaturated hydrocarbons with the empirical formula (C5H8)n. and oxygenates in superheated water make selective extraction possible. With increasingly stringent controls on the use and disposal of traditional organic solvents, the use of superheated water offers environmental advantages. It leaves no residue in products and eliminates the need for solvent disposal. Express Separations originated from the Supercritical Fluids Research Group in the School of Chemistry at the University of Leeds Organisation Faculties The various schools, institutes and centres of the University are arranged into nine faculties, each with a dean, pro-deans and central functions:
Further information. Peter Hammond Peter Hammond may be:
in full Uniform Resource Locator Address of a resource on the Internet. The resource can be any type of file stored on a server, such as a Web page, a text file, a graphics file, or an application program. : www.expsep.co.uk. |
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