摘要:
The separation of gaseous mixtures by gas chromatography, e.g. mixtures of hydrogen isotopes, is carried out in one or more columns having either an ascending or descending temperature profile. Preferably, two or more columns are used in series and comprising a column with an ascending temperature profile, preceded and/or succeeded by a column with a descending temperature profile.
摘要:
Gas chromatographic methods and apparatus are disclosed whereby improved separation times and efficiency are achieved by provision of a time-programmable curvilinearly-shaped negative temperature gradient along the length of the chromatographic column (2). The gas phase sample traveling through the column (2) always passes to a column zone having a lower temperature than the previous column zone. Accordingly, upon elution, sample band-widths are compressed. Separation times may be decreased when compared to conventional isothermal or temperature programmed gas chromatography.