A comparative study of the influence of restricted diffusion upon the moving rate of the solute in various forms of chromatography

The conditions under which the moving rate of a solute in chromatography is influenced by restricted diffusion are investigated. It appears that this phenomenon does not occur in practice in gas-liquid and liquid-liquid chromatography. In molecular sieve chromatography, the calculated eluent flow rate for the onset of the phenomenon agrees with the flow rate at which it has been observed

Determination of complex association constants from gas chromatographic data

The basic expressions for the determination of complex association constants from gas chromatographic data in terms of the activities of the reactants are derived. The advantage of using a reference compound in obtaining association constants is show

Determination of complex association constants from gas chromatographic data

The basic expressions for the determination of complex association constants from gas chromatographic data in terms of the activities of the reactants are derived. The advantage of using a reference compound in obtaining association constants is show

Peak broadening in paper chromatography and related techniques : IV. The mechanism of the mass transfer term in paper chromatography

The mechanism of peak broadening in paper chromatography is investigated by comparing the peak widths obtained in chromatography with those caused only by diffusion, for a set of amino acids of widely differing RF values and with eight kinds of Whatman paper. The results show that longitudinal diffusion occurs both in the mobile and the stationary phase in paper chromatography. The mass transfer term is composed of a contribution of unevenness of flow throughout the paper and a contribution of the slowness of attainment of the partition equilibrium between the mobile and the stationary phase. The resistance to attainment of equilibrium resides predominantly in the mobile phase

Peak broadening in paper chromatography and related techniques VI. The efficiency of various kinds of chromatography paper and thin-layer cellulose powder for the separation of amino acids

The efficiency of several chromatography papers and thin-layer cellulose powders for the separation of amino acids is investigated, using the minimum elution time for a given resolution as the criterion

Peak broadening in paper chromatography and related techniques : III. Peak broadening in thin-layer chromatography on cellulose powder

The mechanism of peak broadening in thin-layer chromatography on cellulose powder was investigated by comparing the peak widths obtained in chromatography with those caused only by diffusion in the cellulose powder, for a set of amino acids of widely differing RF values and six kinds of cellulose powder. The results are interpreted in terms of longitudinal diffusion in the mobile and the stationary phase and resistance to mass transfer in the mobile phase