silica gel is used in chromatography as a stationary phase. In column chromatography, the stationary phase is most often composed of silica gel particles of 40–63 μm. Different particle sizes are used for different kinds of column chromatography as the particle size is related to surface area.

Application

Silica particles used in chromatography have a high surface area, a requirement for good analytical retention. ... They are available for analytical columns and high-, middle- and low-pressure preparative applications.