PURPOSE: To enhance the purity of 4,4'-dihydroxydiphenylsulfone in a single process without requiring an excessive purifying process while suppressing the production of an isomer as a by-product by allowing phenol to react with sulfuric acid under satisfactory conditions of time and temp. in the presence of a suspending agent and an entrainer.
CONSTITUTION: Phenol is allowed to react with sulfuric acid under satisfactory conditions of time and temp. in the presence of a suspending agent and an azeotropic agent to obtain the objective compd. The pref. amt. of phenol used is about 2-3 to 1 mol, especially about 2.2-1 mol based on the amt. of sulfuric acid. The phenol, together with the suspending agent, is heated to about 100-120°C, the sulfuric acid is then added and they are heated to about >120°C, preferably about 150-200°C. The suspending agent is preferably isoparaffin 'ISOPAR H(R)' and the entrainer used for removing water is, e.g. 'ISOPAR E(R)'.
JIYOON TOMUKO
UIRIAMU TEII ANZOBINO
ARAN ABURAMUSON
