To improve energy efficiency of prior art processes while preserving the standards of quality and total yield of desired end products, a process for the preparation of phenolic compounds is proposed. The process of the invention comprises working-up of the cleavage product mixtures by distillation, which comprises resolving the cleavage product mixture into at least three fractions in a single distillation step by feeding the cleavage product mixture to the side of a distillation column, removing a first fraction comprising the ketone at the top of the distillation column, removing a second fraction comprising the phenolic compound at the bottom of the distillation column, and removing a third fraction comprising unreacted the alkylaryl compound and the hydroxy ketone, and water, as side stream, whereby the side stream take-off is situated above the feed of cleavage product mixture to the distillation column, characterized by removing heat from the distillation column, whereby the heat take-off is situated above the side stream take-off of the third fraction, and a process for separating phenol from cleavage product mixtures, wherein the cleavage product mixture prior feeding into the distillation column, is preheated to a temperature of above 70° C. at standard pressure, preferably to a temperature of above 100° C., more preferably to a temperature between 110° C. and 180° C., most preferred to a temperature of about 140° C. to 146° C., and an apparatus suitable therefore.