Abstract: In preparing a sample of a liquid material, particularly a sample suitable for chromatographic analysis, an apparatus and method are provided whereby dissolved precipitatable material is removed from the liquid material by precipitation followed by filtering to obtain a liquid sample which can be suitably analyzed. In a preferred embodiment a combination of dilution and cooling are used to precipitate trinitrotoluene from a solution containing sulfuric and nitric acids prior to the chromatographic analysis of the remaining sample liquid material.

Abstract: A sample containing reactive component is preconditioned in a sample conditioner in a manner which precludes reactions therein and passed to an analyzer through a conduit located in a passageway maintained at a desired temperature by heat exchange with hot air. After the analysis is completed, the sample is purged from the analyzer through the separate conduit extending from the analyzer through said passageway back to the sample conditioner.

Abstract: A gas chromatographic apparatus especially useful in analyzing low boiling materials is provided with means for flowing a pressurized liquid sample through the sampling valve, during the sampling period, in order to reduce the possibility of trapping bubbles of vaporized sample in the sampling valve.