Apparatus and method for preparing bisphenol A

Patent metadata

Field	Value
Publication number	US-10442746-B2
Application number	US-201615769599-A
Country	US
Kind code	B2
Filing date	Nov 21, 2016
Priority date	Nov 19, 2015
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

The present invention relates to an apparatus and a method for preparing bisphenol A, and provides an apparatus and a method for preparing bisphenol A that can increase the energy efficiency of the entire process by utilizing an internal heat source.

First claim

The invention claimed is:

1. An apparatus for preparing bisphenol A comprising:
a first crystallizer to which a bisphenol A concentration stream containing a reaction product that phenol and acetone are reacted is introduced to crystallize bisphenol A and to discharge an adduct of crystallized bisphenol A and phenol;
a first solid-liquid separator in which the adduct of crystallized bisphenol A and phenol in said first crystallizer is introduced thereto, and separated from a mother liquid and discharged;
a phenol introduction port in which a phenol stream is introduced into the adduct of crystallized bisphenol A and phenol discharged from said first solid-liquid separator to discharge the mixed stream of phenol with said adduct of crystallized bisphenol A and phenol;
a first heat exchanger in which said phenol stream is heated before said phenol stream is introduced;
a second heat exchanger in which the adduct of crystallized bisphenol A and phenol in the mixed stream flowing out to said phenol introduction port is melted to discharge the molten stream; and
a second crystallizer to which the molten stream discharged from said second heat exchanger is introduced to recrystallize bisphenol A and to discharge the adduct of crystallized bisphenol A and phenol.

2. The apparatus for preparing bisphenol A according to claim 1 , wherein the first heat exchanger comprises a separation line for separating pentane present in said phenol stream.

3. The apparatus for preparing bisphenol A according to claim 2 , wherein the separation line introduces the separated pentane into the second crystallizer.

4. The apparatus for preparing bisphenol A according to claim 1 , wherein the first heat exchanger heats the phenol stream by introducing a heat source of 120° C. or lower.

5. The apparatus for preparing bisphenol A according to claim 2 , wherein the first heat exchanger comprises a vent for discharging pentane and said vent is connected to the separation line to separate pentane.

6. The apparatus for preparing bisphenol A according to claim 1 , wherein the second heat exchanger melts the adduct of crystallized bisphenol A and phenol by introducing steam having a pressure of 200 kPa to 500 kPa.

7. The apparatus for preparing bisphenol A according to claim 1 , comprising a return line for returning the adduct of crystallized bisphenol A and phenol discharged from the first solid-liquid separator, wherein the second heat exchanger and the phenol introduction port are installed on the return line, and a stream flowing out through said return line is again mixed with the adduct of crystallized bisphenol A and phenol discharged from the first solid-liquid separator.

8. The apparatus for preparing bisphenol A according to claim 1 , further comprising a main reactor in which a reaction product that phenol and acetone are reacted is discharged through a reaction product stream, and a flasher in which said reaction product stream is introduced and separated into a bisphenol A concentration stream and a phenol concentration stream,
wherein the bisphenol A concentration stream separated from said flasher is introduced into the first crystallizer and the mother liquid stream separated in the first solid-liquid separator flows out to said main reactor.

9. The apparatus for preparing bisphenol A according to claim 1 , further comprising a second solid-liquid separator in which the adduct of crystallized bisphenol A and phenol, and the mother liquid, flowing out from the second crystallizer are separated and discharged.

10. The apparatus for preparing bisphenol A according to claim 9 , further comprising a bisphenol A refining line for discharging the molten stream of the adduct of crystallized bisphenol A and phenol discharged from the second solid-liquid separator.

11. The apparatus for preparing bisphenol A according to claim 10 , further comprising a bisphenol A refining drum into which the molten stream flowing out through a bisphenol A refining line is introduced.

Assignees

• Lg Chemical Ltd

Inventors

• Kim Tae Woo
• Lee Sung Kyu
• Shin Joon Ho

Classifications

• C07C37/84 Primary

  by crystallisation · CPC title

• C07C37/685

  Processes comprising at least two steps in series · CPC title

• C07C37/74

  by distillation · CPC title

• C07C39/16

  Bis-(hydroxyphenyl) alkanes; Tris-(hydroxyphenyl)alkanes · CPC title

• C07C37/68 Primary

  Purification; separation; Use of additives, e.g. for stabilisation {(C07C37/004 and C07C37/005 take precedence)} · CPC title