The present invention relates to devices and processes for the introduction of a liquid sample into an apparatus for gas chromatographic analysis. A sample is injected into a vaporization chamber positioned upstream of a gas chromatographic column. The vaporization chamber is equipped with a means to feed a carrier gas selectively into the chamber, the chamber being kept at a temperature at least equal to the boiling temperature of the solvent at the operating pressure. A separation is effectuated between the sample and its carrier solvent, the solvent vapor is exhausted through an exhaust duct. Thereafter, the flow of carrier gas is restored to the chamber and the separated solvent is exhausted from the chamber through a separate outline into a gas chromatographic column.