abstract |
This invention relates to an Eco-friendly method of preparation of high purity tetrabromobisphenol-A through the bromination of bisphenol-A (BPA) with a combination of bromide and bromate ions in organic solvent and water, reacting bromide salt of alkali or alkaline earth metal/hydrobromic acid and bromate as alkali/alkaline earth metal salt, optionally adding 12 N hydrochloric acid in case of metal bromide or equivalents in case of hydrobromic acid, adding alkyl sulfate salts having C6-C18 carbon chain as a surfactant at 5 to 45 °C over a period of 4 to 5 h under stirring, separating the crystalline (50-70 %) product; washing and drying of the product at 100 °C, and charging the organic layer containing un-reacted bisphenol-A, mono-, di- and tri-bromo derivatives and TBBPA with additional bisphenol-A and repeating the above process to yield 95-100 % of TBBPA in the subsequent batches. |