US5457197A
Expired / Lapsed
US
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Monomer recovery from multi-component materials
Assignee: Honeywell International Inc
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Filing: 1994-04-08
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Granted: 1995-10-10
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Expires: 2014-04-08
Abstract
Abstract A process for recovering monomer from multi-component waste material that includes a hydrolyzable polymer, the process including contacting the multi-component waste material with water and subjecting the resulting mixture to heat and pressure to form a liquid aqueous portion which mainly includes depolymerization products of the hydrolyzable polymer and a water insoluble portion which mainly includes components other than the depolymerization products; separating the liquid aqueous portion and the water insoluble portion; subjecting the separated aqueous portion to a pressure that is lower than that of step (a) and heat to produce a residue and a distillate which contains monomer; and separating the monomer in the distillate from other components in the distillate. The process is particularly useful for recovering caprolactam from waste materials that include nylon 6.
Inventors
- 👤 Stylianos Sifniades
- 👤 Alan B. Levy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 05:59
CPC Classifications
C; C07; C07D; C07D201/00; C07D201/02; C07D201/12
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
131 words
A process for recovering monomer from a multi-component polymeric waste material that includes at least one hydrolyzable polymeric component, comprising: (a) subjecting a mixture of water and the multi-component polymeric waste material to heat and pressure to form a liquid aqueous solution which includes as a major constituent a mixture of depolymerization products of the hydrolyzable polymeric component and a water insoluble portion which includes as a major constituent a mixture of materials other than the depolymerization products; (b) separating the liquid aqueous solution and the insoluble portion; (c) flashing and heating the liquid aqueous solution to produce a distillate which contains at least one type of monomer that formed the hydrolyzable polymeric component and a residue; and (d) separating the monomer in the distillate from other components in the distillate.
Claim 2
Dependent Claim
131 words
A process for recovering monomer from a multi-component polymeric waste material that includes at least one hydrolyzable polymeric component, comprising: (a) subjecting a mixture of water and the multi-component polymeric waste material to heat and pressure to form a liquid aqueous solution which includes as a major constituent a mixture of depolymerization products of the hydrolyzable polymeric component and a water insoluble portion which includes as a major constituent a mixture of materials other than the depolymerization products; (b) separating the liquid aqueous solution and the insoluble portion; (c) flashing and heating the liquid aqueous solution to produce a distillate which contains at least one type of monomer that formed the hydrolyzable polymeric component and a residue; and (d) separating the monomer in the distillate from other components in the distillate.
Claim 3
Dependent Claim
27 words
A process according to claim 1, wherein step (a) comprises subjecting the waste material/water mixture to a pressure at least equal to the vapor pressure of water.
Claim 4
Dependent Claim
34 words
A process according to claim 1, wherein step (a) comprises subjecting the waste material/water mixture to a temperature that is at least about 10° C. above the melting point of the hydrolyzable polymeric component.
Claim 5
Dependent Claim
26 words
A process according to claim 1, wherein step (c) comprises subjecting the liquid aqueous solution to a pressure of about 10 kPa to about 1400 kPa.
Claim 6
Dependent Claim
25 words
A process according to claim 1, wherein the hydrolyzable polymeric component is selected from the group consisting of nylon 6, nylon 66 and polyethylene terephthalate.
Claim 7
Dependent Claim
20 words
A process according to claim 1, wherein the hydrolyzable polymeric component comprises a polyamide and the monomer comprises a lactam.
Claim 8
Dependent Claim
33 words
A process according to claim 1, wherein the hydrolyzable polymeric component comprises a polyamide and the monomer comprises at least one of the group consisting of a dicarboxylic acid and an alkylene diamine.
Claim 9
Dependent Claim
33 words
A process according to claim 1, wherein the hydrolyzable polymeric component comprises a polyester and the monomer comprises at least one of the group consisting of a dicarboxylic acid and a dihydric alcohol.
Claim 10
Dependent Claim
121 words
A process for recovering caprolactam from carpet material that includes nylon 6 and non-nylon 6 components, comprising: (a) subjecting a mixture of water and the carpet material to heat and pressure to form a liquid aqueous solution which includes as a major constituent a mixture of nylon 6 depolymerization products and a water insoluble portion which includes as a major constituent a mixture of non-nylon 6 components; (b) separating the liquid aqueous portion and the water insoluble portion; (c) subjecting the liquid aqueous portion to a pressure that is lower than that of step (a) and heat to produce a residue and a distillate which contains caprolactam; and (d) separating the caprolactam in the distillate from other components in the distillate.
Claim 11
Dependent Claim
121 words
A process for recovering caprolactam from carpet material that includes nylon 6 and non-nylon 6 components, comprising: (a) subjecting a mixture of water and the carpet material to heat and pressure to form a liquid aqueous solution which includes as a major constituent a mixture of nylon 6 depolymerization products and a water insoluble portion which includes as a major constituent a mixture of non-nylon 6 components; (b) separating the liquid aqueous portion and the water insoluble portion; (c) subjecting the liquid aqueous portion to a pressure that is lower than that of step (a) and heat to produce a residue and a distillate which contains caprolactam; and (d) separating the caprolactam in the distillate from other components in the distillate.
Claim 12
Dependent Claim
36 words
A process according to claim 9, wherein step (a) comprises subjecting the carpet/water mixture to a temperature of about 240° to about 370° C. and a pressure at least equal to the vapor pressure of water.
Claim 13
Dependent Claim
38 words
A process according to claim 9, wherein the amount of water contacted with the carpet material is from about 0.5 to 5 parts of water per one part nylon 6 present in the carpet material, based on weight.
Claim 14
Dependent Claim
52 words
A process according to claim 9, wherein the carpet material is in the form of a stream and the water is in the form of a stream and the carpet material stream and the water stream are contacted countercurrently to effect extraction of the nylon 6 depolymerization products from the carpet material.
Claim 15
Dependent Claim
42 words
A process according to claim 9, wherein step (a) comprises subjecting the carpet/water mixture to sufficient heat and pressure to initiate depolymerization of nylon 6 and extract the resulting nylon 6 depolymerization products from the carpet material into the liquid aqueous portion.
Claim 16
Dependent Claim
19 words
A process according to claim 9, wherein step (b) comprises decanting, filtering, or a combination of decanting and filtering.
Claim 17
Dependent Claim
32 words
A process according to claim 9, wherein about 90 to 98 weight % of the nylon 6 present in the carpet material is included in the liquid aqueous portion after step (b).
Claim 18
Dependent Claim
14 words
A process according to claim 9, wherein step (c) is effected without a catalyst.
Claim 19
Dependent Claim
24 words
A process according to claim 9, further comprising recycling the residue from step (c) to mix with the carpet material feed in step (a).
Claim 20
Dependent Claim
27 words
A process according to claim 9, wherein the carpet material comprises a carpet having nylon 6 face fiber and a backing material that includes non-nylon 6 components.
Claim 21
Dependent Claim
31 words
A process according to claim 18, wherein the non-nylon 6 components include at least one material selected from the group consisting of jute, polypropylene, latex, calcium carbonate, clay and hydrated alumina.
Claim 22
Dependent Claim
36 words
A process according to claim 9, wherein the liquid aqueous solution of step (a) includes about 5 to about 75 weight % nylon 6 depolymerization products, based on the total weight of the liquid aqueous solution.
Claim 23
Dependent Claim
41 words
A process according to claim 9, wherein the water insoluble portion of step (a) includes about 90 to about 99 weight % non-nylon 6 components, based on the total weight of the water insoluble portion exclusive of absorbed or entrained water.
Claim 24
Dependent Claim
131 words
A process for recovering caprolactam from a carpet material that includes nylon 6 and non-nylon 6 components, comprising: (a) introducing the carpet material and water into a first reactor; (b) subjecting the resulting mixture to heat and pressure to form a liquid aqueous portion which includes as a major constituent a mixture of nylon 6 depolymerization products and a water insoluble portion which includes as a major constituent a mixture of non-nylon 6 components; (c) separating the liquid aqueous solution and the water insoluble portion; (d) introducing the liquid aqueous solution into a second reactor; (e) subjecting the liquid aqueous solution to heat and pressure sufficient to produce a residue and a distillate which contains caprolactam; and (f) separating the caprolactam from other components in the distillate produced in step (e).
Claim 25
Dependent Claim
131 words
A process for recovering caprolactam from a carpet material that includes nylon 6 and non-nylon 6 components, comprising: (a) introducing the carpet material and water into a first reactor; (b) subjecting the resulting mixture to heat and pressure to form a liquid aqueous portion which includes as a major constituent a mixture of nylon 6 depolymerization products and a water insoluble portion which includes as a major constituent a mixture of non-nylon 6 components; (c) separating the liquid aqueous solution and the water insoluble portion; (d) introducing the liquid aqueous solution into a second reactor; (e) subjecting the liquid aqueous solution to heat and pressure sufficient to produce a residue and a distillate which contains caprolactam; and (f) separating the caprolactam from other components in the distillate produced in step (e).
Claim 26
Dependent Claim
76 words
A process according to claim 22, wherein the carpet material is in the form of a stream and the water is in the form of a stream and the first reactor is an extruder, and step (b) comprises contacting countercurrently the carpet material stream and the water stream in the extruder while being subjected to a temperature of about 280° to about 370° C. and a pressure at least equal to the vapor pressure of water.
Claim 27
Dependent Claim
14 words
A process according to claim 22, wherein step (c) is performed in the extruder.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-10-09 | 1999-04-10 | 1999-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-10-09 | 2003-04-10 | 2003-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-10-09 | 2007-04-10 | 2007-10-10 | $7700.00 | Window Closed / Lapsed |