Oxidation of 1-butene to butanone in the presence of homogeneous catalyst Pd + HPA (H₁₂P₃Mo₁₈V₇O₈₅) followed by regeneration of the catalyst with O₂ proceeds with selectivity 97.5%. Side products of the process are acetic acid (1.4%) and condensed compounds С₇Н₁₂О₂, С₈Н₁₄О₂, С₆Н₆О₂, and С₈Н₁₀О₂ (total 1.1%). In the course of the catalyst regeneration at 170°C under O₂ pressure, the compounds C₆–C₈ are completely oxidized to CO₂ and acetic acid. n-Butanal is absent in the reaction products, that permits readily to separate butanone as a water azeotrope from the reduced catalyst.