Extraction process using low-boiling solvents under press - and subsequent evaporation, esp. for concentrating organic trace substances

摘要

The sample is extracted with a solvent which is gaseous under normal conditions, but which is liquefied under pressure. After separation the solvent is removed by reducing the pressure and allowing it to revert to gas. The solvent is pref. n-butane. The solvent contg. extract is pref. transferred slowly from the autoclave to an evaporation vessel (e.g. through a capillary) under the autoclave pressure, and simultaneously allowed to evaporate, leaving the extract. The method is esp. suitable for concentrating org., easily volatile materials which are decomposed by heat, e.g. components of exhaust gases and air, perfumes and pharmaceuticals from plants, aromatic substances from plants and fruits and trace materials from lungs, stomach, blood and sputum. Also for dry cleaning of garments.