Question

how might you perform a column chromatography separation of compounds which are not colored

Answer 1

Performing a column chromatography of not coloured compound is simple..

1. Check the TLC of the compoound to be purified with a suitable system wherein the products are visible in the UV light or Iodine or Spray reagents or HPLC analysis (if all the other tests are negative).

2.Develope a suitable TLC solvent system wherein all the spots are visible with some possible separation.

3. The compounds are not coloured does not mean that the compounds are not identifiable.

4. Preferably start the elution of the column with a non polar solvent like petroleum ether or hexane and slowly increase the polarty depending on the TLC system separations and elute accordingly.

5. The principle of chromatography gives the separation of compounds with coloured identification by various techniqeus rather than the only the coloured compounds are separations.

Plenty of examples are available in the literature about this.