Process for purifying phenol

摘要

A process for purifying and recovering phenol present in a mixed solution containing phenol and one or more compounds capable of forming azeotropic mixtures with phenol wherein an additive which is at least one compound belonging to the following groups 1 to 5 is added to the mixed solution and the resulting mixture is distilled: group 1: dialkylene glycols having 2-10 carbon atoms, polyalkylene glycols having 2-10 carbon atoms, and the ethers thereof, group 2: alkanediols having 2-20 carbon atoms, group 3: ethanolamine-type compounds represented by the formula (1) shown below, group 4: lactam compounds represented by the formula (2) shown below, group 5: quinoline, sulfolane, and N,N-dimethylimidazolidinone, (1) wherein R1 represents an alkyl group having 1-6 carbon atoms, a cycloalkyl group having 1-6 carbon atoms, a monohydroxyalkyl group having 1-6 carbon atoms or a hydrogen atom, m represents an integer of 1-4, and X represents a hydroxyl group, an amino group or a hydrogen atom provided that R1 and X may conjointly represent a group which can be formed by removing respectively one hydrogen atom from R1 and X, respectively, and connecting the rests of R1 and X to form a cyclic ring, (2) wherein R2 represents an alkyl group having 1-6 carbon atoms, a cycloalkyl group having 1-6 carbon atoms, a monohydroxyalkyl group having 1-6 carbon atoms, or a hydrogen atom, and n represents an integer of 3-7.