Production of cumene hydroperoxide

The invention comprises a process for oxidising cumene in the liquid phase with molecular oxygen to give an oxidation product containing cumene hydroperoxide and unreacted cumene, separating, by distillation of the oxidation product, an overhead fraction containing materials boiling lower than cumene hydroperoxide and a concentrated cumene hydroperoxide fraction and recycling the overhead cumene fraction to the oxidation, wherein at least part of the overhead cumene fraction is fractionally distilled to remove materials boiling lower and/or materials boiling higher than cumene before being recycled to the oxidation. Prior to the fractional distillation of the overhead cumene fraction, that fraction may be passed through and recovered from the process in which the concentrated cumene hydroperoxide fraction is decomposed into phenol and acetone. The latter decomposition may take place in the presence of an acid catalyst such as sulphuric acid and in the presence or absence of added solvents such as acetone.