CHROMATOGRAPHIC SEPARATION OF SOME BENZENESULFONATES ON BONDED-PHASE AND POROUS GRAPHITIC CARBON PACKINGS

Separation characteristics of some benzenesulfonates on conventional reversed-phase C18 and porous graphitic carbon stationary phases are studied. Selectivities of porous graphitic packings were found to depend on the concentration of the organic modifier. Also, the mechanism of separation seems to be different between the two stationary phases where hydrophobic interactions are the major forces contributing to retention in alkyl stationary phases. More complex  separation mechanisms are responsible for retention on graphitic packings. In addition, a narrow bore column with a porous graphitic stationary phase was found advantageous and resulted in good and fast separations. Application of a potential step in the negative direction resulted in highly improved separations at much lower retention times.