Process for the purification of bisphenol

A process for preparing BPA with 99.95% (weight) purity and Hazen (APHA) less than 5 from acetone and benzophenol in the optional presence of sulfonic acid ionic exchange agent denatured by mercaptoamines and/or thiazolidines and/or thiocarboxylic acids, in which (a) adjusting the phenol solution to the concentration of 10-40% (by weight) p,p-BHA under 60-80 DEG C, (b) feeding the prepared solution to series-parallel connected towers, in which (c) in the first distillation step, water, residual acetone and selective benzophenol are removed from the reaction solution, then (d) in the second distillation step, the anhydrous solution at the bottom of the tower is adjusted to the concentration of 70-97% p,p-BPA (by weight), (e) in the third distillation step, components that are hard to evaporate or non-volatile are moved from the so obtained solution, then (f) in the fourth distillation step, the easily volatile and residual benzophenol are removed from the p,p-BPA, then (g) obtaining molten p,p-BPA from the bot