CA1101890A - Hydrolytic decomposition method and apparatus - Google Patents
Hydrolytic decomposition method and apparatusInfo
- Publication number
- CA1101890A CA1101890A CA303,929A CA303929A CA1101890A CA 1101890 A CA1101890 A CA 1101890A CA 303929 A CA303929 A CA 303929A CA 1101890 A CA1101890 A CA 1101890A
- Authority
- CA
- Canada
- Prior art keywords
- chamber
- polyurethane
- diamine
- reactor
- polyol
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000000354 decomposition reaction Methods 0.000 title claims description 19
- 230000003301 hydrolyzing effect Effects 0.000 title claims description 13
- 238000000034 method Methods 0.000 title claims description 9
- 239000007787 solid Substances 0.000 claims abstract description 17
- 229920005862 polyol Polymers 0.000 claims abstract description 16
- 150000003077 polyols Chemical class 0.000 claims abstract description 16
- 150000004985 diamines Chemical class 0.000 claims abstract description 12
- 229920006395 saturated elastomer Polymers 0.000 claims abstract description 9
- 239000007788 liquid Substances 0.000 claims abstract description 6
- 238000000926 separation method Methods 0.000 claims abstract description 4
- 239000004814 polyurethane Substances 0.000 claims description 14
- 229920002635 polyurethane Polymers 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 11
- 238000001816 cooling Methods 0.000 claims description 3
- 239000011496 polyurethane foam Substances 0.000 abstract description 6
- 229920005830 Polyurethane Foam Polymers 0.000 abstract description 5
- 238000010438 heat treatment Methods 0.000 description 6
- 239000006260 foam Substances 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 230000007062 hydrolysis Effects 0.000 description 4
- 238000006460 hydrolysis reaction Methods 0.000 description 4
- 150000001412 amines Chemical class 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 229910000514 dolomite Inorganic materials 0.000 description 1
- 239000010459 dolomite Substances 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- -1 poly propylene Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J11/00—Recovery or working-up of waste materials
- C08J11/04—Recovery or working-up of waste materials of polymers
- C08J11/10—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation
- C08J11/14—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation by treatment with steam or water
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J3/00—Processes of utilising sub-atmospheric or super-atmospheric pressure to effect chemical or physical change of matter; Apparatus therefor
- B01J3/04—Pressure vessels, e.g. autoclaves
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2375/00—Characterised by the use of polyureas or polyurethanes; Derivatives of such polymers
- C08J2375/04—Polyurethanes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/62—Plastics recycling; Rubber recycling
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Health & Medical Sciences (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
Porous solids as open cell polyurethane foams are rapidly heated and hydrolytically decomposed into separate polyol component and diamine component by con-tacting the porous solid with saturated steam in a heated vacuum chamber. Separation of high quality liquid polyol and diamine is achieved.
Porous solids as open cell polyurethane foams are rapidly heated and hydrolytically decomposed into separate polyol component and diamine component by con-tacting the porous solid with saturated steam in a heated vacuum chamber. Separation of high quality liquid polyol and diamine is achieved.
Description
The present invention relates to the hydro-lytic decomposition of porous polyurethane solids.
The recovery of polyurethane scrap material, such as polyurethane foam, has been the subject of con-siderable inventive effort. Despite this effort, poly-urethane foam is still commercially disposed ofken in land fill~ It is apparent that a need exists for expedient methods and apparatus for recovery of such materials.
Among the approaches proposed for recovery~
hydrolysis is known to offer certain advantages particularly if it can eliminate or reduce a need for large scale use of organic solvents~ The low thermal conductivity of materials such as polyurethanes, however, normally is a limitation in gaseous hydrolysis methods due to extended warm-up periods requlred before conditions satis-factory for hydrolysis are obtained. Such warm-up periods are troublesome even thouyh catalysts may speed the decomposition reaction after hydrolytic decomposition conditions are attained.
Another difficulty presented with hydrolytic decomposition methods is that of water content as well as amine content in the recovered polyol. Seemingly low levels of water and amine can markedly reduce the value of the recovered polyol and such value, understandably, is ; integral factor for determining competitiveness of the hy8rolytic process.
This invention provides for rapid heating of porous solids as polyurethane foams and is especially advanta~eous for hydrolytic decomposition of open cell polyurethane foams and like materials. Separation of high quality polyol and di~nes can be obtained.
, ~ . .
1 ~
~ .
In accordance with the present invention, there is provided in a method of hydrolytic decomposition o~
porous polyurethane solids in a chamber and .separation of liquid polyol and diamine decomposition proaucts there-from, the improvement which comprises: A. admitting saturated steam into the chamber that i9 evacuated and that contains the polyurethane to provide at least 30 atmospheres therein; B. maintaining hydrolytic decompo-sition conditions within the chamber fo:r a period su:Eficient to decompose the polyurethane; C. releasing gaseous effluent from the upper portion of the chamber; D.
evacuating the chamber to remove diamine and water there~
from; and E. cooling the chamber and collecting the liquid polyol from the lower portion thereof.
The present invention is descrlbed furthér, by ~:
way of illustration, with reference to the accompanyin~
drawing, wherein;
Figure 1 sho~s in schematic relationship the various components of apparatus suitable to carry out this invention.
.
Re~erring to the drawing, the preferred general ~:
; steps of this invention comprise introducing porous solid into the vacuum chamber, evacuating the vacuum chamber ;~
having the porous solid therein to remove residual air (.e.g., to pressure well below 10 1 atmospheres, more prefer- :
ably below about 3 x lQ 2 atmospheres~, admitting high pressure saturated w~ter vapor into the vacuum chamber .
to provide a pressure therein of about 30 atmospheres or greater while heating the walls o~ the YaCuum chamber to a temperature in a range that prevents substantial . .
., .
The recovery of polyurethane scrap material, such as polyurethane foam, has been the subject of con-siderable inventive effort. Despite this effort, poly-urethane foam is still commercially disposed ofken in land fill~ It is apparent that a need exists for expedient methods and apparatus for recovery of such materials.
Among the approaches proposed for recovery~
hydrolysis is known to offer certain advantages particularly if it can eliminate or reduce a need for large scale use of organic solvents~ The low thermal conductivity of materials such as polyurethanes, however, normally is a limitation in gaseous hydrolysis methods due to extended warm-up periods requlred before conditions satis-factory for hydrolysis are obtained. Such warm-up periods are troublesome even thouyh catalysts may speed the decomposition reaction after hydrolytic decomposition conditions are attained.
Another difficulty presented with hydrolytic decomposition methods is that of water content as well as amine content in the recovered polyol. Seemingly low levels of water and amine can markedly reduce the value of the recovered polyol and such value, understandably, is ; integral factor for determining competitiveness of the hy8rolytic process.
This invention provides for rapid heating of porous solids as polyurethane foams and is especially advanta~eous for hydrolytic decomposition of open cell polyurethane foams and like materials. Separation of high quality polyol and di~nes can be obtained.
, ~ . .
1 ~
~ .
In accordance with the present invention, there is provided in a method of hydrolytic decomposition o~
porous polyurethane solids in a chamber and .separation of liquid polyol and diamine decomposition proaucts there-from, the improvement which comprises: A. admitting saturated steam into the chamber that i9 evacuated and that contains the polyurethane to provide at least 30 atmospheres therein; B. maintaining hydrolytic decompo-sition conditions within the chamber fo:r a period su:Eficient to decompose the polyurethane; C. releasing gaseous effluent from the upper portion of the chamber; D.
evacuating the chamber to remove diamine and water there~
from; and E. cooling the chamber and collecting the liquid polyol from the lower portion thereof.
The present invention is descrlbed furthér, by ~:
way of illustration, with reference to the accompanyin~
drawing, wherein;
Figure 1 sho~s in schematic relationship the various components of apparatus suitable to carry out this invention.
.
Re~erring to the drawing, the preferred general ~:
; steps of this invention comprise introducing porous solid into the vacuum chamber, evacuating the vacuum chamber ;~
having the porous solid therein to remove residual air (.e.g., to pressure well below 10 1 atmospheres, more prefer- :
ably below about 3 x lQ 2 atmospheres~, admitting high pressure saturated w~ter vapor into the vacuum chamber .
to provide a pressure therein of about 30 atmospheres or greater while heating the walls o~ the YaCuum chamber to a temperature in a range that prevents substantial . .
., .
- 2 -b ~L
.
L condensation of water vapor thereon (e.y., 200C or higher)~
2 releasing the saseous ef~luent comprising decomposition product
.
L condensation of water vapor thereon (e.y., 200C or higher)~
2 releasing the saseous ef~luent comprising decomposition product
3 from the vacuum chamber through a vacuum chamber exhaust valve,
4 cooling the gaseous e~fluent from the exhaust valve in the con S denser whereby water and decomposition product as diamine may be 6 obtained, preferably continuing evacuation to pressures below 7 about 10-1 atmosphere (more preferably 2 x 10 2 or below) in the 8 vacuum cham~er to dry and puxify the liqluid residue (e.g.
9 polyol) in the bottom of the vacuum chamber, and ~inally releasing 1~ the vacuum in the cooled vacuum chamber and collecting the liquid 11 component.
12 Heating of the porous solid to hydrolytic decomposition 13 conditlons occurs rapidly (i.e~,wit~in ahaut 10 mlnutes or less 14 desirably as little as about 1-3 minutes) because it reaches a temperature corresponding to the vapor pressuxe of steam admitted 16 to the vacuum chamber nearly instantaneously. This is so even 17 though porous solid as open pore flexible polyurethane foam is 18 initially compressed to volumes of one fifth or less its original 19 volume in the vacuum chamber. (Other porous solids include solid closed pore polyurethane which has been comminuted into small 21 pieces (preferably about 1 mm or less) and desirably placed into 22 perforated containers suitable for confining them in the vacuum 23 during hydrolysis).
24 The boiler used may be any standard type boiler that provides saturated steam at least greater 26 than 30 atmospheres, more preerably 35 atmospheres or more 27 up to pressure~ which the system may convenientLy handle~
28 Noxmally, pressures between about 35-60 atmospheres ca~ be 29 employed in the vacuum chamber to give advantageous results without resort to more costly high pressure equipment.
31 ~pon hydrolytic decomposition of the porous solld, 32 e.g., open cell polyurethane flexible foam, saseous effluent 1 is released from the vacuum chamber and cooled in a 2 condenser wherein water and li~uid or solid diamines are collected.
3 Release of carbon dioxide also occurs and such gas can be 4 vented from the condenser~ Advantageously, the cool condenser may comprise a plurality of small metallic pieces to insure 6 maximum suxface area for collection of diamine component 7 Usually, a period of up to about 30 minutes is 8 required for complete hydrolytic decomp~sition o~ polyurethane 9 foam at saturated vapor pressures of about 30-40 at~spheres, although ac~ion of catalysts as well as higher pressures may 11 reduce the tLme required. Continuance of admission of the 12 saturated steam to maintain such pressures permits the endothenmic 13 reaction to proc~ed expeditiously.
14 Advantageously, the evacuation of the vacuum chamber can be continued after hydrolytic decomposition~ In thi~ way, 16 ~he li~uid decomposition component (eag. polyol) i on-17 veniently freed of excess water and-diamines thereby increasing the 18 value of this component. Thereafter, ~he vacuum ch~mber can l9 be drained of polyol and the process began again, or, for example continued by introducing porous solid from a standby 21 chamberO
22 As previously mentioned, although porous solids as 23 open cell polurethane oam, particularly flexible polyurethane 24 foam, are preferred, other material of low thermal conductivity may also be rapidly heated in accordance with this invention 26 when it i8 finely divided to permit its exposure over a 27 laxge surface area to the saturated water vaporO However, . .
; 28 rapid heating of porous solids as open cell polyurethane oam Z9 takes full advantage of the m-thod and apparatus herein.
1 T~e following examples illus~rate this invention 2 and are not intended as limiting the scope thereof as many 3 modifications will be apparent according to the hereinb~fore 4 and hereinafter descriptions of this inveIItion.
~ e~
6 Using an apparatus as illustrated in the drawing, 7 urathane foam, at a density of 48 kg/m3 is stuffed into the 8 reactor (i.e.~ vacuum chamber) and compre~;sed to about 240 9 kg/m3. The reactor is sealed and the vacuum pump started~
The reactor with its exhaust system, includîng condenserst 11 is evacuated to an absolute pressure of approximately 2 kPa 12 (15 mm Hg or 0.3 psia~. The high pressure boiler is energized 13 and brought up to pressure, about 10,300 XPa at 315C~ The 14 reactor exhaust valve is clo~ed - vacuum pump operation continues - and the electric heaters on the reactor sidewalls and in the 16 reactor base and top flange are energized, with the heater 17 contxollers set at the desired wall temperature ~200 to 250C~.
18 Steam is immediately admitted to the reactor until a reactor 19 pressure of 3.8 MPa to 4.1 MPa ~550 psig to 600 psig) is attained. As soon as this pressure is reached, a 250 to 21 255C temperature is immediately established within the 22 reactor. Steam flow rate is then reduced until reactor pressure 23 is just maintained for a period of not more than 30 minutes, 24 when the reactions will have been well completed. The steam valve is then closed and the reactor exhaust valve is par~ially 26 opened. The exhaust valve is modulated so as not to exceed a 27 pressure of 6.5 kPa absolute (O.g psia) in the vacuum system.
28 This prevents an excessive flow of vapor into the vacuum pump.
29 When the reactor pressure has again been reduced to 2 kPa absolute ~0~3 psia) at a reactor temperature o~ about 250C, 1 the reac~or heaters are de~energized and the reackor is 2 cooled to room temperature. The polyol is then drained 3 from the reactor for use. (The polyol has less than 1~4%
4 by weigh~ amine and less than 1/4~ by weight water)~ The to}uene diamine is removed from the condenser system by 6 heating and draining, re-evaporating, or with a sol~ent flusho 7 Tha residue, composed of fillers such as crushed dolomite 9 ~ poly propylene, etc~ is removed from the zeactor and th~
9 equipment is then ready or re~use~
10 ~, 11 Urethane foam, at a density of 36.8 Kg/m3 is stuffed 12 or packed into a basket constructed ~rom perfora~ed stainless 13 steel sheet and compressed to a density of 500 kg/m3~ The 14 basket with its contents is then placed in the reactor. The reactor is sealed and the pro¢edure of Example 1 is ~ollowed 16 leading to similar diamine and polyol separatLon.
17 ~ e~
18 Non-porous urethane is reduced to small chips of less 19 than 1 mm in any dimension which are placed in a perforated metal or metal mesh bas~tO ~he basket, loaded with ~ethane 21 chips is placed in the reactor. The reactor is ealed, 22 whereupon the procedure of Example 1 is followed leading to 23 desired polyol and diamine components.
24 It is to be understood that the apparatus as shswn in the drawing may be advantageously modified such that the boiler surrounds 26 the vacuum chamber thereby eliminating the need for separate 27 heating element to heat the va~uum chamber~ On the other hand, 28 the apparatus as shown permits ready construction and ha~ the 29 advantage that the exterior of the vacuum chamber may be heated to some xtent by the entering saturated steam condensing on the _ _ 1 inner walls thereof thereby prevPnting undesirably high 2 temperature walls contacting porous solid in the absence of 3 saturated water vapor. Still further~ the apparatus as 4 illustrated in the drawing advantageously allows for precise control of reaction conditions so that high quality decomposition 6 produc~s ma~ be consistently obtained.
9 polyol) in the bottom of the vacuum chamber, and ~inally releasing 1~ the vacuum in the cooled vacuum chamber and collecting the liquid 11 component.
12 Heating of the porous solid to hydrolytic decomposition 13 conditlons occurs rapidly (i.e~,wit~in ahaut 10 mlnutes or less 14 desirably as little as about 1-3 minutes) because it reaches a temperature corresponding to the vapor pressuxe of steam admitted 16 to the vacuum chamber nearly instantaneously. This is so even 17 though porous solid as open pore flexible polyurethane foam is 18 initially compressed to volumes of one fifth or less its original 19 volume in the vacuum chamber. (Other porous solids include solid closed pore polyurethane which has been comminuted into small 21 pieces (preferably about 1 mm or less) and desirably placed into 22 perforated containers suitable for confining them in the vacuum 23 during hydrolysis).
24 The boiler used may be any standard type boiler that provides saturated steam at least greater 26 than 30 atmospheres, more preerably 35 atmospheres or more 27 up to pressure~ which the system may convenientLy handle~
28 Noxmally, pressures between about 35-60 atmospheres ca~ be 29 employed in the vacuum chamber to give advantageous results without resort to more costly high pressure equipment.
31 ~pon hydrolytic decomposition of the porous solld, 32 e.g., open cell polyurethane flexible foam, saseous effluent 1 is released from the vacuum chamber and cooled in a 2 condenser wherein water and li~uid or solid diamines are collected.
3 Release of carbon dioxide also occurs and such gas can be 4 vented from the condenser~ Advantageously, the cool condenser may comprise a plurality of small metallic pieces to insure 6 maximum suxface area for collection of diamine component 7 Usually, a period of up to about 30 minutes is 8 required for complete hydrolytic decomp~sition o~ polyurethane 9 foam at saturated vapor pressures of about 30-40 at~spheres, although ac~ion of catalysts as well as higher pressures may 11 reduce the tLme required. Continuance of admission of the 12 saturated steam to maintain such pressures permits the endothenmic 13 reaction to proc~ed expeditiously.
14 Advantageously, the evacuation of the vacuum chamber can be continued after hydrolytic decomposition~ In thi~ way, 16 ~he li~uid decomposition component (eag. polyol) i on-17 veniently freed of excess water and-diamines thereby increasing the 18 value of this component. Thereafter, ~he vacuum ch~mber can l9 be drained of polyol and the process began again, or, for example continued by introducing porous solid from a standby 21 chamberO
22 As previously mentioned, although porous solids as 23 open cell polurethane oam, particularly flexible polyurethane 24 foam, are preferred, other material of low thermal conductivity may also be rapidly heated in accordance with this invention 26 when it i8 finely divided to permit its exposure over a 27 laxge surface area to the saturated water vaporO However, . .
; 28 rapid heating of porous solids as open cell polyurethane oam Z9 takes full advantage of the m-thod and apparatus herein.
1 T~e following examples illus~rate this invention 2 and are not intended as limiting the scope thereof as many 3 modifications will be apparent according to the hereinb~fore 4 and hereinafter descriptions of this inveIItion.
~ e~
6 Using an apparatus as illustrated in the drawing, 7 urathane foam, at a density of 48 kg/m3 is stuffed into the 8 reactor (i.e.~ vacuum chamber) and compre~;sed to about 240 9 kg/m3. The reactor is sealed and the vacuum pump started~
The reactor with its exhaust system, includîng condenserst 11 is evacuated to an absolute pressure of approximately 2 kPa 12 (15 mm Hg or 0.3 psia~. The high pressure boiler is energized 13 and brought up to pressure, about 10,300 XPa at 315C~ The 14 reactor exhaust valve is clo~ed - vacuum pump operation continues - and the electric heaters on the reactor sidewalls and in the 16 reactor base and top flange are energized, with the heater 17 contxollers set at the desired wall temperature ~200 to 250C~.
18 Steam is immediately admitted to the reactor until a reactor 19 pressure of 3.8 MPa to 4.1 MPa ~550 psig to 600 psig) is attained. As soon as this pressure is reached, a 250 to 21 255C temperature is immediately established within the 22 reactor. Steam flow rate is then reduced until reactor pressure 23 is just maintained for a period of not more than 30 minutes, 24 when the reactions will have been well completed. The steam valve is then closed and the reactor exhaust valve is par~ially 26 opened. The exhaust valve is modulated so as not to exceed a 27 pressure of 6.5 kPa absolute (O.g psia) in the vacuum system.
28 This prevents an excessive flow of vapor into the vacuum pump.
29 When the reactor pressure has again been reduced to 2 kPa absolute ~0~3 psia) at a reactor temperature o~ about 250C, 1 the reac~or heaters are de~energized and the reackor is 2 cooled to room temperature. The polyol is then drained 3 from the reactor for use. (The polyol has less than 1~4%
4 by weigh~ amine and less than 1/4~ by weight water)~ The to}uene diamine is removed from the condenser system by 6 heating and draining, re-evaporating, or with a sol~ent flusho 7 Tha residue, composed of fillers such as crushed dolomite 9 ~ poly propylene, etc~ is removed from the zeactor and th~
9 equipment is then ready or re~use~
10 ~, 11 Urethane foam, at a density of 36.8 Kg/m3 is stuffed 12 or packed into a basket constructed ~rom perfora~ed stainless 13 steel sheet and compressed to a density of 500 kg/m3~ The 14 basket with its contents is then placed in the reactor. The reactor is sealed and the pro¢edure of Example 1 is ~ollowed 16 leading to similar diamine and polyol separatLon.
17 ~ e~
18 Non-porous urethane is reduced to small chips of less 19 than 1 mm in any dimension which are placed in a perforated metal or metal mesh bas~tO ~he basket, loaded with ~ethane 21 chips is placed in the reactor. The reactor is ealed, 22 whereupon the procedure of Example 1 is followed leading to 23 desired polyol and diamine components.
24 It is to be understood that the apparatus as shswn in the drawing may be advantageously modified such that the boiler surrounds 26 the vacuum chamber thereby eliminating the need for separate 27 heating element to heat the va~uum chamber~ On the other hand, 28 the apparatus as shown permits ready construction and ha~ the 29 advantage that the exterior of the vacuum chamber may be heated to some xtent by the entering saturated steam condensing on the _ _ 1 inner walls thereof thereby prevPnting undesirably high 2 temperature walls contacting porous solid in the absence of 3 saturated water vapor. Still further~ the apparatus as 4 illustrated in the drawing advantageously allows for precise control of reaction conditions so that high quality decomposition 6 produc~s ma~ be consistently obtained.
Claims
1. In a method of hydrolytic decomposition of porous polyurethane solids in a chamber and separation of liquid polyol and diamine decomposition products therefrom, the improvement which comprises:
A. admitting saturated steam into the chamber that is evacuated and that contains the polyurethane to.
provide at least 30 atmospheres therein;
B. maintaining hydrolytic decomposition con-ditions within the chamber for a period sufficient to decompose the polyurethane;
C. releasing gaseous effluent from the upper portion of the chamber;
D. evacuating the chamber to remove diamine and water therefrom; and E. cooling the chamber and collecting the liquid polyol from the lower portion thereof.
A. admitting saturated steam into the chamber that is evacuated and that contains the polyurethane to.
provide at least 30 atmospheres therein;
B. maintaining hydrolytic decomposition con-ditions within the chamber for a period sufficient to decompose the polyurethane;
C. releasing gaseous effluent from the upper portion of the chamber;
D. evacuating the chamber to remove diamine and water therefrom; and E. cooling the chamber and collecting the liquid polyol from the lower portion thereof.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US82691577A | 1977-08-22 | 1977-08-22 | |
| US826,915 | 1977-08-22 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1101890A true CA1101890A (en) | 1981-05-26 |
Family
ID=25247834
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA303,929A Expired CA1101890A (en) | 1977-08-22 | 1978-05-24 | Hydrolytic decomposition method and apparatus |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPS5443277A (en) |
| BE (1) | BE869868A (en) |
| CA (1) | CA1101890A (en) |
| DE (1) | DE2834325C2 (en) |
| FR (1) | FR2400933A1 (en) |
| GB (1) | GB1601787A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03102809A (en) * | 1989-09-14 | 1991-04-30 | Toshiba Corp | Disassembling method for molded device |
| DE3942881C2 (en) * | 1989-12-23 | 1997-08-21 | Hasso Von Bluecher | Procedure for the disposal of loaded activated carbon filters |
| JP4751977B2 (en) * | 2005-07-04 | 2011-08-17 | エコマテリアル株式会社 | Organic waste treatment equipment |
| JP7285729B2 (en) * | 2019-08-08 | 2023-06-02 | 三菱重工業株式会社 | waste treatment equipment |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1041650A (en) * | 1964-12-14 | 1966-09-07 | John Joseph Perkins | Sterilization process |
| DE2207379B2 (en) * | 1972-02-17 | 1978-06-22 | Phoenix Gummiwerke Ag, 2100 Hamburg | Process for the recovery of polyethers from polyether urethane plastics |
| CA1016955A (en) * | 1972-12-18 | 1977-09-06 | Ford Motor Company Of Canada | Low pressure hydrolysis of polyurethane foam and recovery of products |
| DE2442387C3 (en) * | 1974-09-04 | 1981-09-10 | Bayer Ag, 5090 Leverkusen | Process for the continuous hydrolytic breakdown of hydrolyzable plastic waste |
-
1978
- 1978-05-23 GB GB21431/78A patent/GB1601787A/en not_active Expired
- 1978-05-24 CA CA303,929A patent/CA1101890A/en not_active Expired
- 1978-08-04 DE DE2834325A patent/DE2834325C2/en not_active Expired
- 1978-08-09 FR FR7823455A patent/FR2400933A1/en active Granted
- 1978-08-21 BE BE189988A patent/BE869868A/en not_active IP Right Cessation
- 1978-08-22 JP JP10151878A patent/JPS5443277A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| DE2834325C2 (en) | 1983-07-14 |
| FR2400933A1 (en) | 1979-03-23 |
| DE2834325A1 (en) | 1979-03-01 |
| FR2400933B1 (en) | 1983-03-04 |
| JPS5443277A (en) | 1979-04-05 |
| GB1601787A (en) | 1981-11-04 |
| BE869868A (en) | 1978-12-18 |
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