| 摘要 |
A process for preparing high-purity bisphenol A is provided to obtain bisphenol A having a purity of 99.8% or higher in a simple manner and to impart a low color index and high-temperature stability in a molten state to bisphenol A. The process comprises the steps of: (a) reacting phenol with acetone in the presence of an acidic ion exchanger and a sulfur-containing cocatalyst to obtain a mixture containing bisphenol A(BPA), phenol, BPA isomers, unreacted acetone and water; (b) forming bisphenol-A-phenol adduct crystals continuously from the mixture; (c) carrying out phase separation of the adduct of step (b) to obtain a solid phase and a liquid phase; (d) washing the solid phase with a phenol-containing solution to obtain a washed solid phase and a second liquid phase; (e) performing distillation of the liquid phase and the second liquid phase to obtain a dehydrated solution containing p,p-BPA, BPA isomers and water; (f) introducing 90 wt% or more of the dehydrated solution to step (a); (g) adding phenol to the solid phase obtained from step (d) to obtain a homogeneous mixture containing p,p'-BPA, BPA isomers and water; (h) forming bisphenol-A-phenol adduct crystals continuously from the homogeneous mixture; (i) carrying out phase separation of the crystals of step (h) to obtain a second solid phase; (j) washing the second solid phase with a phenol-containing solution to obtained washed adduct; and (k) heating the adduct to 120 deg.C or higher to remove phenol.
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