Three–dimensional surfaces, based on a large set of experi-mental data, have been built to investigate and describe the interrelations between different physico–chemical properties of two-phase liquid systems, the operating conditions of the planetary centrifuge, and the stationary phase retention. The wide range of alteration of interfacial tension, density, and viscosity differences between two phases has been provided by changing the composition of liquid systems containing an organic solvent, an extracting reagent, water and a mineral salt, the organic solvents, and extracting reagents of different nature being considered. A great body of data presents a possibility of estimating the contributions from all the enumerated physico-chemical properties of liquid systems to the stationary phase retention.