Question

Please outline only the main steps of an efficient column chromatographic separation of a non-polar compound A from a medium polar compound B and a non-polar chemical (C). C is slightly less polar than A.

Answer 1

Chromatography is a separation technique used to purify the individual components for the given mixture. Column chromatography is one of the chromatography method used to purify individual components using a vertical glass apparatus called column and a stationary phase (for example silica gel), a mobile phase (different solvent combinations).

In the given mixture of A, B, and C, Since A is nonpolar than C and B is a medium polar compound, one has to choose the mobile phase with solvent combinations varying from less percentage of polar solvent in combination with a nonpolar solvent to more percentage of polar solvent in combination with a nonpolar solvent.

For the stationary phase, one has to pack the column bed around 10 cm length (with the increase in the length of the stationary phase the separation of the components will be better).

For the combinations of solvents, one can use hexane as nonpolar solvent and ethyl acetate as polar solvent. The ideal way to get better separation will be to elute the column starting from 100 % hexane and by gradually increasing the percentage of polar solvent ethyl acetate (like 5%, 10%, 15% and so on)