Adsorbents, for column chromatography

Alumina and silica gel are the most commonly used adsorbents for column chromatography, just as they are for TLC. The quality of these adsorbents is high in that they have uniform particle size and high specific area. The higher the specific area, the faster the equilibrium of the solute between the mobile and solid phases is established and the narrower the bands. High specific areas on the order of several hundred m /g are common for good grades of alumina and silica gel. 

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