Due to its use in both analytical and preparative application, column chromatographic technique is more useful than the other two chromatographic methods: paper chromatography and TLC . The determination of the number of the component present in the mixture can be done by this process. Along with this, substantial quantities of those samples get separated and purified by the column chromatography for the subsequent analysis. Whereas, the paper chromatography is solely responsible for the analytical determination.
Column: A thin layer of silica gel or alumina on a glass, metal or plastic plate acts as the stationary phase in the column chromatography. It performs on a much larger scale. The same materials are packed within a vertical glass column.
Procedure: A mobile phase is used for the movement of the component mixture through a stationary phase by the column chromatography. Different sample components possess different affinities towards the mobile and stationary phases. They emerge from the stationary phase at different times. Depending on the nature of the mixture the stationary phase and the mobile phase is chosen. This leads to achieve the best possible separation of its components.
Generally silica or alumina is used as the stationary phase in the chemical laboratory. A thick white slurry is then produced by mixing the stationary phase with the solvent. To maximize the sample separation, a liquid mobile phase is chosen. This liquid either can be water or any other organic solvent.
Elution: Eluting the constituent compounds of the sample from the chromatography column is done by a process in which the compounds are washed through a column by using a solvent. This process is known as an elution. And the solvent is referred as the eluent. Eluent is a term used in chromatography which denotes the same thing as the mobile phase. However, it specifically refers to the mobile phase at the inlet of the column.