| 摘要 |
<p>A process for producing a high purity 2,4'-dihydroxydiphenylsulfone (2,4'-isomer) comprising separating 2,4'-isomer from 4,4'-dihydroxydiphenylsulfone (4,4'-isomer) by adding a hydroxide of an alkali metal in an amount which is the total of an amount by mol 1.6 to 2.2 times as great as the amount by mol of 2,4'-isomer and an amount by mol 0.8 to 1.2 times as great as the amount by mol of 4,4'-isomer to a solution of a mixture of 2,4'-isomer and 4,4'-isomer containing 15 % by weight or more of 2,4'-isomer in water, to allow 2,4'-isomer to remain dissolved in water in the form of a dialkali metal salt thereof and 4,4'-isomer to be precipitated from the solution in the form of a monoalkali metal salt thereof. A carbonate of an alkali metal may also be used. In order to accelerate the operation, an excess amount of the alkali may be added, which is subsequently neutralized. A high purity 2,4'-isomer having a purity of 95 to 99.5 % by weight can be obtained easily with a high yield from a mixture of the isomers containing 15 % by weight or more of 2,4'-isomer.</p> |
