Process for crystallizing bisphenol-A

• US 4,740,634 A
• Filed: 10/20/1986
• Issued: 04/26/1988
• Est. Priority Date: 10/20/1986
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Kissinger, Gaylord M., Gomes de Matos, Isabel M.
• Primary Examiner(s): LONE, WERREN
• Application Number:
  US06/920,465
• Time in Patent Office: 554 Days
• Field of Search: 568/724, 568/723, 568/722, 568/727, 568/748, 568/749
• US Class Current: 568/724
• CPC Class Codes: C07C 37/84 by crystallisation
• CPC Class Codes: C07C 39/16 Bis-(hydroxyphenyl) alkanes; Tris-(hydroxyphenyl)alkanes

Abstract

A process for crystallizing bisphenol-A which comprises:

a. adding water to a mixture comprising bisphenol-A, about 0.5 to 15 weight percent of diphenol isomers and impurities, said mixture essentially free of phenol,

b. maintaining the combined water and said mixture of (a) at a temperature sufficient to melt the solid material of step (a),

c. adiabatically cooling the water and said mixture to below about 90° C.,

d. separating crystallized bisphenol-A from the mother liquor, and

e. washing the crystallized bisphenol-A with an organic solvent which is at least substantially insoluble in water.

Claims

1. A process for crystallizing bisphenol-A which comprises:

a. adding water to a mixture comprising bisphenol-A, about 0.5 to 15 weight percent of diphenol isomers and impurities, said mixture essentially free of phenol, the water in a weight ratio of 1;

1 to 3;

1 based on the weight of the said mixture

b. maintaining the combined water and said mixture of (a) at a temperature sufficient to melt the solid material of step (a),

c. adiabatically cooling the water and said mixture to below about 90°

C.,

d. separating crystallized bisphenol-A from the mother liquor, and

e. washing the crystallized bisphenol-A with an organic solvent which is at least substantially insoluble in water.

2. The process in accordance with claim 1 wherein about 3 to 6 weight percent of bisphenol-A isomers and impurities are present.

3. The process in accordance with claim 1 wherein the adiabatically cooling brings the water and said mixture to a temperture between about 45°

and 89°

C.

4. The process in accordance with claim 1 wherein the organic solvent is toluene or methylene chloride.

5. The process in accordance with claim 1 wherein prior to separating crystallized bisphenol-A from the mother liquor, the slurry of crystallized bisphenol-A and mother liquor is contacted with an organic solvent which is at least substantially insoluble in water.