ABSTRACT
Two types of gas chromatography are usually specified (gas being the mobile phase): gas-solid chromatography (or gas-adsorption chromatography), the kind of chromatography used when the mobile phase is a gas, the stationary being a solid (adsorbent); and gas-liquid chromatography, used when the mobile phase is a gas, the stationary being a liquid (absorbent). The real sorbent employed in gas-liquid-solid chromatography is a polyphase sorbent in which a thin film of the stationary liquid phase covers the surface of a solid sorbent. The development of ideas about the role of the adsorption interactions between the chromatographed compounds and the sorbent in gas-liquid-solid chromatography is associated mainly with an accurate consideration of the contribution of retention by individual phases of a real sorbent to the total retention value, and with experimental verification of the equations derived, including verification by independent methods.
