[en] The conditions of the formation have been studied and the compositions have been determined for di-n-butylphosphates of zirconium, thorium, and tetravalent plutonium separated from the solutions of di-n-butylphosphoric acid (DBP,HA) in a mixture of 10 vol.% of tri-n-butylphosphate (TBP) with organic diluents (benzene, carbon tetrachloride, gasoline). It is shown that irrespective of the ratio of HA: zirconium (within the range of 0.66-4.2) the precipitates of the Zr(NO₃)₂A₂ composition are separated in the solutions. Plutonium and thorium form the precipitates of the Pu(NO₃)₂A₂ and ThA₄ composition only from the solutions with gasoline. Chemical analysis and cryoscopic study of the precipitates have been made. It is shown that the polymerization degree of the plutonium compound is about 11. Infrared spectroscopic study of the precipitates has been conducted, and possible structures of the obtained compounds of DBP with metals are