Acetone → BPA phenol

Participants

Reaction Conditions

Reaction Steps

A vertical drum reactor (D=2400 mm, H=10 m) was filled with a mixture composed of 70% microporous Wofatit-KPS cation exchanger and 30% macroporous Wofatit-PK-110 cation exchanger up to 7 m. The reaction mixture obtained by mixing the stream of dewatered post-crystallization liquor containing 8% by weight of bisphenol A and 15.5% by weight of process by-products with the reaction mixture collected from the bottom of the reactor was made to flow through the catalyst bed at 3400 kg/hr. The temperature of the mixture at the inlet to the reactor was 85° C. and its composition was as follows: bisphenol A--642.6 kg/hr, by-products--622.2 kg/hr including o,p-isomers--149.6 kg/hr, phenol--1883.6 kg/hr, acetone--231.2 kg/hr, water--20.4 kg/hr. The composition of the product obtained was the following: bisphenol A--816 kg/hr, by-products--550.8 kg/hr including o,p-isomers--163.2 kg/hr, acetone--192.2 kg/hr, water--40.8 kg/hr, phenol--1800.2 kg/hr. The resulting solution at 85° C. was cooled down to 40° C. to obtain the crystalline bisphenol-A/phenol adduct. The crystals at 1720 kg/hr were subjected to centrifugation to separate them from the mother liquor I and washed with mother liquor II at 344 kg/hr. The colouration of the 50% crystalline adduct solution was 70 APHA. The washed adduct was solved in the phenolic solution obtained as a result of distillation of the phenolic mother liquor I. The resultant solution was recooled to 39° C. to precipitate the bisphenol-A/phenol adduct crystals, the adduct was centrifuged and the mixture was rewashed using a mixture composed of 2000 kg fresh phenol and 1000 kg of regenerated phenol which produced 1376 kg/hr of bisphenol-A/phenol adduct. The colouration of the 50% crystalline adduct solution in ethanol was 5 APHA. The crystals were melted and sent to distillation column to distill a major part of phenol at 160° C. and 10 mm Hg. The remaining phenol was removed by steam distillation to obtain 940 kg of bisphenol A. The bisphenol A product shows the following properties: crystallization point: 156.8° C., colouration of 50% solution 4 APHA, o,p-isomer: trace amounts, codimer: trace amounts, trisphenol: 15 ppm, principal product: 99.96% by weight.

Provenance & Evidence