Speciation of Different Anions of Sulphur:

In its unique application, paper chromatography has been successfully used for speciation studies of sulphur such as S^2-, SO₃^2-, SO₄^2-,S₂O₃^2-, S₄O₆^2- using radiotracer ³⁵S. The Whatman No. 1 filter paper was used along with solvent mixtures of dioxane, n-butyl alcohol-1N ammonia (1:1:1) and acetone-iso- propanol-liquor ammonia (1:1:1). Various spots corresponding to various anions can be identified by radioactivity measurements using a G. M. counter. The R_f values for SO₄^2-,S₂O₃^2-, S₄O₆^2- and S^2- were found to be 0.12, 0.43, 0.54 and 0.77, respectively. Similarly, Rf values for S₂O₃^2- and SO₃^2- were found to be 0.14 and 0.61, respectively.

Paper treated with silicone or paraffin oil permits reversed phase paper chromatography where mobile phase is a highly polar solvent. This technique is referred to as 'reverse-phase PC'. The Commercially available papers coated along with adsorbent or ion-exchange resin offer additional applications of adsorption and ion-exchange paper chromatography.