| 摘要 |
Process for the preparation of tetrabromo-4,4'-alkylidonediphenols The invention is directed to the production of tetrabromo4,4'-alkylidenediphenols, especially tetrabromobisphenol A (TBBA), from the corresponding alkylidenediphenols by oxidative bromination with Br2, HBr3 or HBr and aqueous hydrogen peroxide in presence of an organic solvent and is characterized by a washing treatment, preferably at 50 to 90 .degree.C, of the organic phase containing dissolved tetrabromo4,4'-alkylidenediphenol with an aqueous alkali sulphite solution. Through this washing treatment the tetrabromo compound is obtained in higher purity: simultaneously the mother liquor can be recycled without difficulty.
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