WO2000015589A1 - Liquid vacuum pump seal to reduce contamination in bisphenol-a - Google Patents
Liquid vacuum pump seal to reduce contamination in bisphenol-a Download PDFInfo
- Publication number
- WO2000015589A1 WO2000015589A1 PCT/US1999/013885 US9913885W WO0015589A1 WO 2000015589 A1 WO2000015589 A1 WO 2000015589A1 US 9913885 W US9913885 W US 9913885W WO 0015589 A1 WO0015589 A1 WO 0015589A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- phenol
- liquid
- bpa
- bisphenol
- improved process
- Prior art date
Links
- 239000007788 liquid Substances 0.000 title claims abstract description 25
- 229940106691 bisphenol a Drugs 0.000 title claims abstract description 11
- 238000011109 contamination Methods 0.000 title description 10
- IISBACLAFKSPIT-UHFFFAOYSA-N bisphenol A Chemical compound C=1C=C(O)C=CC=1C(C)(C)C1=CC=C(O)C=C1 IISBACLAFKSPIT-UHFFFAOYSA-N 0.000 claims abstract description 68
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 claims abstract description 56
- 238000000034 method Methods 0.000 claims abstract description 20
- 239000002002 slurry Substances 0.000 claims abstract description 14
- 239000011734 sodium Substances 0.000 claims abstract description 10
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims abstract description 8
- 229910052708 sodium Inorganic materials 0.000 claims abstract description 8
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 27
- 239000003054 catalyst Substances 0.000 claims description 11
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 10
- 238000006243 chemical reaction Methods 0.000 claims description 10
- 239000002253 acid Substances 0.000 claims description 7
- 239000000356 contaminant Substances 0.000 claims description 7
- 238000004064 recycling Methods 0.000 claims description 4
- 239000013078 crystal Substances 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims description 2
- 238000002844 melting Methods 0.000 claims description 2
- 230000008018 melting Effects 0.000 claims description 2
- 239000012535 impurity Substances 0.000 abstract description 4
- 239000012452 mother liquor Substances 0.000 description 9
- 239000003518 caustics Substances 0.000 description 8
- 229920000642 polymer Polymers 0.000 description 8
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 6
- 230000002378 acidificating effect Effects 0.000 description 5
- 238000000746 purification Methods 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 239000000463 material Substances 0.000 description 4
- 238000002360 preparation method Methods 0.000 description 4
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 description 3
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 229920000515 polycarbonate Polymers 0.000 description 3
- 239000004417 polycarbonate Substances 0.000 description 3
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 2
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- 125000003118 aryl group Chemical group 0.000 description 2
- 239000007795 chemical reaction product Substances 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 239000003822 epoxy resin Substances 0.000 description 2
- LNEPOXFFQSENCJ-UHFFFAOYSA-N haloperidol Chemical compound C1CC(O)(C=2C=CC(Cl)=CC=2)CCN1CCCC(=O)C1=CC=C(F)C=C1 LNEPOXFFQSENCJ-UHFFFAOYSA-N 0.000 description 2
- 229920000647 polyepoxide Polymers 0.000 description 2
- 239000000376 reactant Substances 0.000 description 2
- 150000003460 sulfonic acids Chemical class 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 description 1
- 239000004593 Epoxy Substances 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 229920001429 chelating resin Polymers 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000006482 condensation reaction Methods 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 235000011187 glycerol Nutrition 0.000 description 1
- 150000002334 glycols Chemical class 0.000 description 1
- 239000003456 ion exchange resin Substances 0.000 description 1
- 229920003303 ion-exchange polymer Polymers 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 150000002989 phenols Chemical class 0.000 description 1
- 229920001467 poly(styrenesulfonates) Polymers 0.000 description 1
- 229920001230 polyarylate Polymers 0.000 description 1
- 229920001601 polyetherimide Polymers 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 229910001415 sodium ion Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000003828 vacuum filtration Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C39/00—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring
- C07C39/12—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring polycyclic with no unsaturation outside the aromatic rings
- C07C39/15—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring polycyclic with no unsaturation outside the aromatic rings with all hydroxy groups on non-condensed rings, e.g. phenylphenol
- C07C39/16—Bis-(hydroxyphenyl) alkanes; Tris-(hydroxyphenyl)alkanes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C19/00—Rotary-piston pumps with fluid ring or the like, specially adapted for elastic fluids
- F04C19/004—Details concerning the operating liquid, e.g. nature, separation, cooling, cleaning, control of the supply
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/68—Purification; separation; Use of additives, e.g. for stabilisation
- C07C37/70—Purification; separation; Use of additives, e.g. for stabilisation by physical treatment
- C07C37/84—Purification; separation; Use of additives, e.g. for stabilisation by physical treatment by crystallisation
Definitions
- This invention relates to a rotary vacuum pump employing a particular pump seal liquor in order to eliminate contamination in the production of dihydric phenols particularly Bisphenol-A which is used in substantial quantities to synthesize polymers particularly aromatic carbonate polymers.
- the novel feature of this invention is employing liquid phenol as the vacuum pump seal liquor as will be described hereinafter.
- Bisphenol-A has been an extremely useful chemical for many decades. As a difunctional monomer, it has been used in the preparation of numerous polymers. For example Bisphenol-A [2,2'-bis(4-hydroxyphenyl)propane] has been utilized in preparing such materials as epoxy resins, polyetherimides, polyarylates and, in particular, polycarbonates.
- BPA Bisphenol-A
- the purity of the Bisphenol-A (hereinafter referred to as BPA) employed in the polymer reaction need not be that high. Epoxy resins only need BPA of approximately 95% purity.
- the impurity which is present in the greatest amount in such systems is generally orthopara BPA.
- the purity of the BPA must be substantially higher.
- BPA Purities of BPA of about 99.50% or higher preferably 99.80 or 99.90% or higher are desirable and in many cases necessary for the preparation of BPA polycarbonates. Therefore there has been substantial attention directed to the preparation and purification of BPA.
- the art is replete with references directed to the preparation of BPA. Usually this is done by the condensation of phenol with acetone in the presence of a catalyst system.
- the catalyst is an acidic catalyst.
- one of the particularly useful catalyst systems in the patent art and employed commercially was hydrochloric acid.
- the hydrochloric acid is extremely corrosive and ordinary metallic reactors and piping must be changed on a frequent basis. Obviously glass lined reactors or certain alloyed metals can be employed, however, these are quite expensive. In later years there seems to be the tendency to use heterogeneous acidic catalyst system wherein the acidic catalyzation occurs at the catalyst surface and is actually bound to the catalyst. In this manner the "acid" does not flow with the unused reactants and BPA.
- Such catalyst systems are generally sulfonated polystyrenes which are substantially crosslinked such as the Amberlites and like materials. However, such sulfonated polystrenes, because they contain sulfonic pendent groups may form sulfonic acids.
- the sulfonic acids, along with hydrochloric acid, if employed as part of or a contaminant in the catalyst system, and any other acids can be very corrosive to the equipment, particularly rotary vacuum pumps. Consequently, aqueous caustic has been used as the liquid vacuum seal in rotary vacuum pumps in order to neutralize the acids in the BPA condensation reaction products generally comprised of BPA, phenol, and water and other materials.
- the reaction products are sent to a crystallizer system wherein a BPA /phenol crystal slurry is formed.
- the slurry is sent to a rotary vacuum filter, equipped with vacuum pumps which pull the slurry through a filter drum.
- a cake (BPA/phenol adduct) is formed on the drum and the extracted liquid often referred to as the mother liquor is recycled to the reactor in which BPA is formed.
- the mother liquor may be subjected to dehydration in order to remove water of reaction and other unwanted materials before recycling the mother liquor back to the reactor.
- the BPA adduct may be redissolved in phenol and sent to a second rotary filter (second stage) equipped with vacuum pull for further purification.
- Another object of this invention is to employ liquid phenol as a seal liquor in rotary vacuum pumps.
- rotary vacuum filters may be employed.
- the rotary vacuum filters are operated under a vacuum wherein the pressure is controlled at a level below atmospheric and operate in a range of 50 mm Hg to about 250 mm Hg absolute.
- the rotary filters may be mechanical liquid ring pumps to provide the vacuum source.
- aqueous caustic (sodium hydroxide/water) solution has been used to provide the liquid seal for these pumps.
- the fans or blades of the pump cannot touch the inside of the pump housing since wear would be extremely extensive.
- the vacuum pump seal liquor is essential to the ability of the pumps to pull a vacuum (reduced pressure) down to the operating level.
- Sodium hydroxide solution has been used as the liquid seal in such pumps when producing BPA as described heretofore.
- acidic and /or basic ionic contamination such as sodium
- BPA is generally prepared by the reaction of phenol and acetone in the presence of an acidic catalyst, such as HC1 or an ion exchange resin. During the reaction, some unwanted by-products and color are formed which affect yield and quality. Also in the filtration of a BPA/phenol adduct slurry generally comprising a liquor (often referred to as a mother liquor), BPA and phenol, the adduct slurry is deliquored by vacuum filtration which slurry comprises BPA and phenol. The mother liquor is essentially recycled back to the reaction for producing BPA as described heretofore.
- an acidic catalyst such as HC1 or an ion exchange resin.
- rotary vacuum filters are used to separate the adduct cake from the mother liquor.
- the process for producing the BPA can be any process and is not critical in the practice of this invention.
- the critical feature is the use of phenol as the liquid in a liquid ring seal rotary pump.
- Another advantage is that it is possible to discontinue the use of sulfuric acid which is required to neutralize the aqueous caustic effluents which are contaminated with phenol.
- phenol is a solid at room temperature
- the phenol used as a liquid seal is kept at a temperature above its melting point under process conditions such that it is in a liquid state, preferably at a temperature of at least about 150° C and more preferably at a temperature of about 150 to about 175° F.
- a small amount of fresh phenol may be continuously fed to the rotary pumps.
- the replaced or used phenol may then be treated for removal of contaminants before recycling the replaced phenol back to the reactor for forming BPA. Since phenol does not neutralize the acid contaminants as described heretofore when employing aqueous caustic, the acid contaminants can be removed by continuously feeding fresh phenol to the rotary vacuum pumps. The replaced or used phenol will carry off the acid contaminants.
- a two stage rotary vacuum pump system is employed to obtain a BPA/phenol cake. After each stage, a BPA/phenol cake is obtained by crystallization and vacuum filtering a BPA/phenol adduct (slurry). After the first stage, the cake is dissolved in phenol and the liquid system is then sent to a second stage or second rotary vacuum pump. In each stage, the rotary vacuum pump has a sodium hydroxide (caustic) liquid vacuum pump seal. Three different flow rates are evaluated and, in each case, the BPA/phenol cake after the second stage is analyzed for sodium (Na) contamination in the BPA/phenol cake. The results obtained are as follows:
- the sodium hydroxide solution employed as a liquid seal is a 6.0 weight % aqueous sodium hydroxide
- Example 1 is repeated except that in place of the caustic liquid seal ring, liquid phenol is employed herein.
- the liquid phenol is at a temperature of about 160° F.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Sealing Using Fluids, Sealing Without Contact, And Removal Of Oil (AREA)
- Sealing Material Composition (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2000570130A JP4455762B2 (en) | 1998-09-16 | 1999-06-21 | Liquid vacuum pump seal to reduce contamination in bisphenol A |
EP99930449A EP1114015A1 (en) | 1998-09-16 | 1999-06-21 | Liquid vacuum pump seal to reduce contamination in bisphenol-a |
KR1020017003457A KR20010073170A (en) | 1998-09-16 | 1999-06-21 | Liquid vacuum pump seal to reduce contamination in bisphenol-a |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/154,289 | 1998-09-16 | ||
US09/154,289 US6130359A (en) | 1998-09-16 | 1998-09-16 | Liquid vacuum pump seal to reduce contamination in bisphenol-A |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2000015589A1 true WO2000015589A1 (en) | 2000-03-23 |
Family
ID=22550760
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1999/013885 WO2000015589A1 (en) | 1998-09-16 | 1999-06-21 | Liquid vacuum pump seal to reduce contamination in bisphenol-a |
Country Status (7)
Country | Link |
---|---|
US (1) | US6130359A (en) |
EP (1) | EP1114015A1 (en) |
JP (1) | JP4455762B2 (en) |
KR (1) | KR20010073170A (en) |
CN (1) | CN1167660C (en) |
TW (1) | TW539665B (en) |
WO (1) | WO2000015589A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004035512A1 (en) * | 2002-10-17 | 2004-04-29 | Idemitsu Kosan Co., Ltd. | Process for producing bisphenol a |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1541542A4 (en) * | 2002-08-28 | 2006-08-09 | Idemitsu Kosan Co | Process for producing bisphenol a |
CN102167659B (en) * | 2011-03-25 | 2013-04-03 | 南通星辰合成材料有限公司 | Method for realizing vacuum rectification and vacuum evaporation of bisphenol A by liquid ring vacuum pump |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0109033A2 (en) * | 1982-11-15 | 1984-05-23 | General Electric Company | Purification of bisphenol-A |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4876391A (en) * | 1988-09-15 | 1989-10-24 | General Electric Company | Process for preparation and purification of bisphenols |
US5243093A (en) * | 1990-09-07 | 1993-09-07 | General Electric Company | Process and composition |
US5315042A (en) * | 1993-03-22 | 1994-05-24 | General Electric Company | Use of partial acetone conversion for capacity increase and quality/yield improvement in the bisphenol-A reaction |
US5414151A (en) * | 1994-05-02 | 1995-05-09 | General Electric Company | Method for making bisphenol |
US5874644A (en) * | 1996-04-12 | 1999-02-23 | Gammill; Ben | Method and system for bisphenol a production using controlled turbulence |
-
1998
- 1998-09-16 US US09/154,289 patent/US6130359A/en not_active Expired - Lifetime
-
1999
- 1999-06-21 JP JP2000570130A patent/JP4455762B2/en not_active Expired - Fee Related
- 1999-06-21 CN CNB998109703A patent/CN1167660C/en not_active Expired - Fee Related
- 1999-06-21 KR KR1020017003457A patent/KR20010073170A/en not_active Application Discontinuation
- 1999-06-21 EP EP99930449A patent/EP1114015A1/en not_active Ceased
- 1999-06-21 WO PCT/US1999/013885 patent/WO2000015589A1/en not_active Application Discontinuation
- 1999-09-03 TW TW088115245A patent/TW539665B/en not_active IP Right Cessation
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0109033A2 (en) * | 1982-11-15 | 1984-05-23 | General Electric Company | Purification of bisphenol-A |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004035512A1 (en) * | 2002-10-17 | 2004-04-29 | Idemitsu Kosan Co., Ltd. | Process for producing bisphenol a |
CN100406421C (en) * | 2002-10-17 | 2008-07-30 | 出光兴产株式会社 | Process for preparing bisphenol A |
Also Published As
Publication number | Publication date |
---|---|
EP1114015A1 (en) | 2001-07-11 |
JP4455762B2 (en) | 2010-04-21 |
US6130359A (en) | 2000-10-10 |
KR20010073170A (en) | 2001-07-31 |
CN1167660C (en) | 2004-09-22 |
CN1318044A (en) | 2001-10-17 |
JP2002524541A (en) | 2002-08-06 |
TW539665B (en) | 2003-07-01 |
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