COUNTERCURRENT CHROMATOGRAPHY FOR THE PRECONCENTRATION AND SEPARATIONOF INORGANIC-COMPOUNDS - INFLUENCE OF PHYSICOCHEMICAL PROPERTIES OF 2-PHASE LIQUID-SYSTEMS ON THE RETENTION OF THE STATIONARY-PHASE

It is demonstrated that hydrophobic systems based on decane and chloro form exhibit different hydrodynamic behavior in columns. The addition of 5% of di-2-ethylhexylphosphoric acid to the solvent improves the re tention of the stationary phase in the column and changes the differen ces in the densities and viscosities of the phase and some other physi cochemical parameters of the system (e.g., interfacial tension) that d etermine the retention. A similar effect was observed on the addition of a solution of ammonium sulfate to the mobile phase. The retention o f the stationary phase in the column is scarcely affected by an increa se in the concentration of ammonium sulfate.