Normally an
inert porous solid, which sorbs the liquid phase. The particle-size range of the support
affects column efficiency and the pressure differential necessary to achieve a given
flow rate. Modifications have been introduced for the achievement of special separations,
in which the solid support is not
inert but is an
active solid.
In capillary columns the inner wall of the column serves as the solid support and
obviates the use of additional porous solids for this purpose.
Source:
PAC, 1993, 65, 819
(Nomenclature for chromatography (IUPAC Recommendations 1993))
on page 830