Procedure for the splitting of bisphenol a.

A cleavage method of bisphenol A for producing a product containing isopropenylphenol and phenol by cleaving a mixture containing bisphenol A together with chroman derivatives and derivatives of flavan formed as byproducts in the process for producing bisphenol A, comprising (1) a cleavage step comprising supplying the mixture containing bisphenol a together with chroman derivatives and derivatives of flavan formed as byproducts in the production process of bisphenol a, a container unfolding and performing a cleavage reaction in the presence of a basic catalyst or acid at a temperature in the range of 150 to 260 ° C in conditions of no greater reduced pressure 40 kPa (300 mmHg), (2) a distillation step comprising supplying the product of the cleavage step formed in the cleavage step vaporous to a distillation column and distilling at a temperature in the range of 13 0 to 200 ° C in conditions of no greater reduced pressure 40 kPa (300 mmHg), and (3) a reflux step of condensing the distillate from the distillation step, refluxing a part thereof to the distillation step at a rate reflux in the range of 0, 01-3, and discharging the waste system.