Bayer Aktiengesellschaft

Bayer Ag Konzernverwaltung Rp

Ignace Hooftman

Claus H Wulff

Kaspar Hallenberger

Jurgen Hinz

Johan Vaes

Kurt-Peter Meurer

Alfred Eitel

Tony Van Osselaer

Werner Verhoeven

Heinrich Steude

Frank Quaeyhaegens

Willy Van Herck

A process for preparing bisphenol A which has a purity of at least 99.95 wt. % of p,p-bisphenol A (BPA). Thermally stable and colour-stable BPA purified in accordance with the invention produces improved thermal and colour stability and improved optical transparency in polymers such as e.g. polycarbonates prepared therefrom.

Process for the purification of bisphenol

The invention relates to a method for the purification by distillation of p,p-bisphenol A from the melt. The p,p-bisphenol A melt thus obtained is highly heat-stable, stable in storage and colour-stable, is free from high-boiling components and no longer contains any surface-active or non-distillable metal, salt, acid or polymer components and no sulphur-containing components; o,p-BPA and phenol are removed and the low-boiling components are scarcely detectable.

Method for the preparation of ultra-pure bisphenol A and the use thereof

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Kruibeke, Belgium

Ignace Hooftman