Method for continuous determination of volatile impurities in contaminated medium
US5460973A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 20, 1994 |
| Grant date | Oct 24, 1995 |
| Priority date | — |
| Expiry date | Dec 20, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/25875
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of optically measuring volatile impurities in contaminated medium using a combination of a distillation process with head space analysis. The method uses a hydrophobic extracting membrane at the surface of an internal reflection element (an optical fiber or an attenuated total reflection crystal). The hydrophobic analytes are extracted into the extracting membrane, from the contaminated medium. By heating the contaminated medium to form a vapor and cooling the sensor element surrounded by the extracting membrane this invention significantly reduces the limit of detection by between two and three orders of magnitude from the prior art. The distillation aspect of the method also serves to protect the extracting membrane surrounding the sensor from damage by the mechanical impurities in the contaminated medium. A simultaneous continuous analysis of several impurities of the contaminated medium is possible by several optical fibers arranged in parallel on the same cooling device, each of which is designed for another contaminate by means of optical filters, wavelengths disperging elements (gratings or prisms) or wavelength selective IR sources or detectors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.