Nova Patents
EP0358992A2

Process for the manufacture of bis-phenols.

Abstract

A process which comprises (a) contacting an excess of a phenol with a ketone in the presence of an acidic ion exchange resin cata­lyst;(b) recovering thereafter a stream from the acidic ion exchange resin catalyst including the dihydric phenol, unreacted phenol, isomers of the desired di­hydric phenol and acid impurities derived from the acidic ion exchange resin catalyst;(c) removing a major portion of the desired di­hydric phenol from the stream of (b);(d) separating the stream including phenol, a small portion of the desired dihydric phenol, isomers of the desired dihydric phenol, and acidic impurities derived from the acidic ion exchange resin catalyst into a major stream and a minor stream by volume;(e) introducing into the minor stream created at step (d) sufficient quantities of a tetraorganoammonium borohydride to effectively neutralize the acidic impur­ities derived from the acidic ion exchange resin catalyst; and(f) recovering from the minorstream desirable dihydric phenol.

EP0358992A2, drawing sheet 1
Sheet 1 of 1

Term

Term ended

Projected expiry passed 23 August 2009, 17.1 years ago.

  1. Priority
  2. Filed
  3. Published
  4. Projected expiry
  5. Today

12 claims: 3 independent, 9 dependent

  1. 1
    A process which comprises (a) contacting an excess of a phenol with a ketone in the presence of an acidic ion exchange resin cata­lyst;(b) recovering thereafter a stream from the acidic ion exchange resin catalyst including the dihydric phenol, unreacted phenol, isomers of the desired di­hydric phenol and acid impurities derived from the acidic ion exchange resin catalyst;(c) removing a major portion of the desired di­hydric phenol from the stream of (b);(d) separating the stream including phenol, a small portion of the desired dihydric phenol, isomers of the desired dihydric phenol, and acidic impurities derived from the acidic ion exchange resin catalyst into a major stream and a minor stream by volume;(e) introducing into the minor stream created at step (d) sufficient quantities of a tetraorganoammonium borohydride to effectively offset the acidic impurities derived from the acidic ion exchange resin catalyst;and (f) recovering from the small stream desirable dihydric phenol.
  2. 2
    The process in accordance with claim 1 wherein the phenol is phenol.
  3. 3
    The process in accordance with claim 1 wherein the ketone is acetone.
  4. 4
    The process in accordance with claim 2 wherein the ketone is acetone, the desired product being bis­phenol-A.
  5. 5
    The process in acordance with claim 4 wherein the organo groups are the same and are methyl.
  6. 6
    The process in accordance with claim 4 wherein the organo groups are the same and are phenyl.
  7. 7
    In a process for preparing a dihydric phenol from the reaction of a phenol and a ketone in the presence of an acidic ion exchange resin catalyst, the improvement comprising the addition to the process of sufficient quantities of a tetraorganoammonium boro­hydride to a minor portion of the split process stream created after the removal from the stream of a major quantity of the desired dihydric phenol to effectively offset acidic impurities provided from the acidic ion exchange resin catalyst, said impurities carried with the desired dihydric phenol in the downstream process­ing steps from the catalyst.
  8. 8
    The process in accordance with claim 7 wherein the phenol is phenol.
  9. 9
    The process in accordance with claim 7 wherein the ketone is acetone.
  10. 10
    The process in accordance with claim 8 wherein the ketone is actone, the desired product being bis­phenol-A.
  11. 11
    The process in accordance with claim 10 where­in the organo groups are the same and are methyl.
  12. 12
    The process in accordance with claim 11 where­in the organo groups are the same and are phenyl.
Independent claims12