摘要 |
In a process for producing 4,4'-dihydroxydiphenylsulfone by reacting phenol with sulfuric acid in the presence of a solvent, an improvement which comprises using at least a member selected from the group consisting of chlorobenzene, dichlorobenzene, trichlorobenzene, chlorotoluene, diethylbenzene, xylene, decalin, tetralin and tetrachloroethane as the solvent and removing said solvent progressively and finally substantially completely from the mixture while maintaining the reaction mixture at a temperature of about 160 DEG to about 200 DEG C. to effect precipitation of 4,4'-dihydroxydiphenylsulfone and isomerization of 2,4'-dihydroxydiphenylsulfone to 4,4'-dihydroxydiphenylsulfone.
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