Decoupled flow and pressure setpoints in an extraction instrument using compressible fluids
US5322626A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 5, 1993 |
| Grant date | Jun 21, 1994 |
| Priority date | — |
| Expiry date | Feb 5, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2030/324
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods and apparatus for extracting sample components from complex matrices using supercritical fluid as the principal extracting solvent are disclosed. The invention takes advantage of the fact that the solvent power of a supercritical fluid is stepwise settable by the parameters of density, modifier concentration, and temperature. Accordingly, methods and apparatus for extracting a component from a sample using fluid flow system having a variable and controllable flow restriction are disclosed. The methods of the present invention comprise the steps of inserting the sample into the sample container section, inputting temperature, pressure, flow rate and extraction time set points. Flow rate is controlled and system pressure regulated by the variable flow restriction. The output stream from the extraction is then expanded through a nozzle and into a trap. In certain embodiments, the trap is filled with chemically active packing material. In other embodiments, a fractionation zone and other analytical instruments are coupled to the apparatus of the present invention. Methods and apparatus for rinsing the extraction instrument and for diluting the extraction fluid are also disclose…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.