METHOD OF EXTRACTION OF PHENOL AND BIPHENOLS Russian patent published in 2007 - IPC C07C37/68 C07C39/04 C07C39/16 

FIELD: chemical industry; methods of extraction of phenol and biphenols from the homogeneous reactionary mixtures.

SUBSTANCE: the invention is pertaining to the method of extraction of phenol and biphenols from the homogeneous reactionary mixtures of the direct oxidation of benzene by hydrogen peroxide. The method includes delivery of the reactionary mixture containing benzene, water, phenol, the sulfolane and the reaction by-products (biphenols) in еру distillation plant consisting of two or more columns for production of one or more products basically consisting of the azeotropic mixture of benzene with water and phenol, and also the product consisting of sulfolane, phenol and the reaction by-products. The stream including sulfolane is mixed with the water solution of the base and benzene for formation of the salts of the phenols and the subsequent stratification of the mixture, extraction by benzene and separation in the flow column containing benzene and sulfolane, which is returned in the reactor. From the same column separate the stream including sodium phenolates in the water solution, which is treated with the sulfuric acid for extraction of the phenols from their salts. At the stage of the extraction separate the extracting solvent, after distillation of which in the tailings bottom product receive the biphenols water solution. The separated organic solvent recirculates in the system. The technical result of the invention is improvement of the process of separation of phenols and biphenols from the complex azeotropic mixtures containing sulfolane.

EFFECT: the invention ensures the improved process of separation of phenols and biphenols from the complex azeotropic mixtures containing sulfolane.

9 cl, 1 ex, 1 dwg, 1 tbl