Vapor detection with high speed gas chromatography
US5108705A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1990 |
| Grant date | Apr 28, 1992 |
| Priority date | — |
| Expiry date | Oct 3, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2030/8405
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Disclosed are a method and apparatus for high speed, selective detection of vapors of specific compounds, particularly nitrogen-containing compounds, utilizing, a bypass branch and high speed gas chromatography for improved selectively and sensitivity of detection. A system with two gas chromatographs (GC's) alternating in series with two pyrolyzers provides two time intervals of detection in a downstream detector, with the second time interval containing signals delayed and further separated relative to signals from the first time interval. The bypass branch, in diverting a portion of the flow of gas samples from passage through the second gas chromatograph and second pyrolyzer, avoids interferences in the first time interval of detection from non-GC-retained compounds decomposed in the second pyrolyzer. Also disclosed is an arrangement for rapid, precise heating of vapor concentrator tubes in which vapors are rapidly focussed and then injected into a GC, and for rapid, precise heating of the GC's.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.