tamis moléculaire

CONT: Le gaz vecteur est séché sur tamis moléculaire [...] Les billes ou bâtonnets de tamis sont introduits dans un cylindre métallique d'environ 100 ml. L'activation ainsi que les régénérations ultérieures peuvent être effectuées dans le four du chromatographe sous balayage de gaz vecteur à 300 °C pendant une nuit.
CONT: Les adsorbants courants sont : l'argile activée et le gel de silice activé [...]; l'alumine activée; les tamis moléculaires (silico-aluminate de soude) [...]

CONT: The dehydrated crystals are interlaced with regularly spaced channels of molecular dimensions, which comprise almost 50% of the total volume of the crystals. ... only those molecules that are small enough to pass through the pores of the crystals can enter the cavities and be adsorbed on the interior surface. This sieving or screening action, which makes it possible to separate smaller molecules from larger ones, is the most unusual characteristic of molecular sieves.
OBS: [The molecular sieves] are used in many fields of technology: to dry gases and liquids, for selective molecular separations based on size and polar properties, as ion-exchangers, as catalysts, as chemical carriers, in gas chromatography, and in the petroleum industry to remove normal paraffins from distillates.