METHOD OF PRODUCING BISPHENOL A AND METHOD OF PREPARING BISPHENOL A/PHENOL MELT

摘要

FIELD: industrial organic synthesis. SUBSTANCE: invention relates to a method of production of light- colored bisphenol A with insignificant residual level of oxygen and phenol. Microcrystalline bisphenol A/phenol adduct is melted at 100-120 C, after which melt is continuously fed under nitrogen atmosphere into top part of distillation system, wherein, at 120- 160 C and pressure 80-200 mbar, content of phenol in the melt drops by 10-25 wt %. Simultaneously, nitrogen is fed into still of distillation column in amount 0.5 to 50% based on the volume of melt fed into column. Rest of phenol is removed from oxygen-free concentrated melt at 180-220 C and partial pressure of nitrogen 1-1.5 bar. In order to obtain melt containing 75-90 wt % bisphenol A and 10-25 wt % phenol with oxygen level below 1 ppm, mixed crystallizate containing 60 wt % bisphenol A and 40 wt % phenol is melted at 100-120 C and melt is treated in the same order as above. EFFECT: improved chromaticity of bisphenol A and improved preparation technology. 2 cl, 3 ex