Method for the preparation of 4-hydroxybiphenyl

摘要

Preparation of 4-hydroxybiphenyl in the form of a non-thixotropic damp product uses alkaline hydrolysis (using an alkali hydroxide) of biphenyl-4-sulphonic acid. The alkali reaction mixture is diluted with water, neutralised with a mineral acid and tempered at a temperature of ≥ 115 degrees C and a pH of ≤ 6.5, under raised pressure.