| 摘要 |
The sample is separated by gas chromatography into a first light fraction and a second heavier fraction in a two column apparatus. The fractions after separation are received on a retention device (AC, CT) and each fraction is analyzed in detail by putting the respective retention devices into a circuit including at least one gas chromatograph and one with a gas-liquid chromatograph (LG-GC). The first gas chromatograph has a capillary pre-column and a capillary column connected in series, a first multi-way valve (V1) to connect the outlet form the pre-column to the first retention device (AC1) for the heaviest fraction, and a second multi-way valve (V2) cooperating with the first and a source of gas under pressure to selectively displace a second lighter fraction from the column to a second retention device (CT, AC2, AC3). A liquid chromatograph and valve assembly (V3, V4) connects the retention devices for the heaviest fraction and a solvent pump to a gas and a liquid chromatograph. The system includes ultra-violet detection of fractions transferred to the chromatograph.
|
