The solvent system used depends upon the behavior of your (crude) product on silica gel. Neat hexane (or a substitute such as petroleum ether or cyclohexane) is often used to wash ‘grease’ (non polar compounds) off the column, whilst neat ethyl acetate (or ether) is often used to elute highly polar compounds.

The solvent system used depends upon the behavior of your (crude) product on silica gel. Neat hexane (or a substitute such as petroleum ether or cyclohexane) is often used to wash ‘grease’ (non polar compounds) off the column, whilst neat ethyl acetate (or ether) is often used to elute highly polar compounds.