US5021253A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Decaffeination of liquid medium
Assignee: Dow Chemical Co
•
Filing: 1989-12-13
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Granted: 1991-06-04
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Expires: 2009-12-13
Abstract
Abstract An improved method of decaffeinating and recovering such from caffeine containing materials without the use of organic solvents, except for regeneration of the resin, carbon or expensive extraction equipment, wherein the method comprises contacting an effective amount of an adsorbent resin with a liquid solution containing caffeine so as to adsorb caffeine from the liquid solution onto the adsorbent resin, where the adsorbent resin is made from a gel copolymer of a monovinyl aromatic monomer and a crosslinking monomer, where the gel copolymer has been post-crosslinked in the swollen state in the presence of a Friedel-Crafts catalyst and can be functionalized with hydrophilic groups if so desired.
Inventors
- 👤 Kari R. Dawson-Ekeland
- 👤 Richard T. Stringfield
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:27
CPC Classifications
A; A23; A23F; A23F3/00; A23F3/36; A23F3/38; A23F3/385; A23F5/00; A23F5/20; A23F5/22; A23F5/223
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
82 words
An improved process of decaffeinating a liquid solution by contacting the liquid solution with an effective amount of an adsorbent resin so as to adsorb caffeine from the liquid solution onto the adsorbent resin, wherein the improvement comprises contacting the liquid solution containing caffeine with an adsorbent resin that is made from a gel copolymer of a monovinyl aromatic monomer and a crosslinking monomer, where the gel copolymer has been post-crosslinked in the swollen state in the presence of a Friedel-Crafts catalyst.
Claim 2
Dependent Claim
82 words
An improved process of decaffeinating a liquid solution by contacting the liquid solution with an effective amount of an adsorbent resin so as to adsorb caffeine from the liquid solution onto the adsorbent resin, wherein the improvement comprises contacting the liquid solution containing caffeine with an adsorbent resin that is made from a gel copolymer of a monovinyl aromatic monomer and a crosslinking monomer, where the gel copolymer has been post-crosslinked in the swollen state in the presence of a Friedel-Crafts catalyst.
Claim 3
Dependent Claim
15 words
The process of claim 1 wherein the post-crosslinked gel copolymer is functionalized with hydrophilic groups.
Claim 4
Dependent Claim
13 words
The process of claim 1 wherein the crosslinking monomer is a polyvinylidene monomer.
Claim 5
Dependent Claim
16 words
The process of claim 3 wherein the polyvinylidene monomer is divinylbenzene, trivinylbenzene, or ethylene glycol diacrylate
Claim 6
Dependent Claim
24 words
The process of claim 4 wherein the monovinyl aromatic monomer is styrene or a derivative of styrene, vinyltoluene, vinylbenzyl chloride, vinylbenzyl alcohol, or vinylnaphthalene.
Claim 7
Dependent Claim
21 words
The process of claim 5 wherein the gel copolymer contains up to about 99.75 weight percent styrene with the balance divinylbenzene.
Claim 8
Dependent Claim
22 words
The process of claim 1 wherein the gel copolymer contains from about 1 to about 45 weight percent of the crosslinking monomer.
Claim 9
Dependent Claim
22 words
The process of claim 7 wherein the adsorbent resin contains from about 4 to about 8 weight percent of the crosslinking monomer.
Claim 10
Dependent Claim
11 words
The process of claim 1 wherein the gel copolymer is chloromethylated.
Claim 11
Dependent Claim
18 words
The process of claim 1 wherein the gel copolymer is post-crosslinked with a polyfunctional alkylating or acrylating compound.
Claim 12
Dependent Claim
17 words
The process of claim 2 wherein the post-crosslinked gel copolymer is functionalized with dimethylamine, trimethylamine or dimethylethanolamine.
Claim 13
Dependent Claim
13 words
The process of claim 2 wherein the post-crosslinked copolymer is functionalized by solvolysis.
Claim 14
Dependent Claim
13 words
The process of claim 2 wherein the post-crosslinked gel is functionalized by sulfonation.
Claim 15
Dependent Claim
22 words
The process of claim 1 wherein the adsorbent resin has a surface area of about 700 to about 2100 m 2 /g.
Claim 16
Dependent Claim
22 words
The process of claim 14 wherein the adsorbent resin has a surface area of about 1000 to about 1800 m 2 /g.
Claim 17
Dependent Claim
19 words
The process of claim 1 wherein the adsorbent resin has a porosity of about 0.10 to about 1.2 cc/cc.
Claim 18
Dependent Claim
19 words
The process of claim 16 wherein the adsorbent resin has a porosity of about 0.7 to about 0.8 cc/cc.
Claim 19
Dependent Claim
17 words
The process of claim 1 wherein the adsorbent resin exhibits a percent shrink/swell below about 7 percent.
Claim 20
Dependent Claim
17 words
The process of claim 18 wherein the adsorbent resin exhibits a percent shrink/swell below about 4 percent.
Claim 21
Dependent Claim
23 words
The process of claim 1 wherein the dry weight capacity of the adsorbent resin ranges from greater than zero to about 4.0 meq/g.
Claim 22
Dependent Claim
23 words
The process of claim 20 wherein the dry weight capacity of the adsorbent resin ranges from greater than zero to about 2.0 meq/g.
Claim 23
Dependent Claim
16 words
The process of claim 1 wherein the liquid solution is a solution of coffee bean extract.
Claim 24
Dependent Claim
23 words
The process of claim 1 wherein the liquid coffee bean extract solution is contacted with the adsorbent resin continuously in a packed column.
Claim 25
Dependent Claim
13 words
The process of claim 1 wherein the liquid solution is a chocolate extract.
Claim 26
Dependent Claim
13 words
The process of claim 1 wherein the liquid solution is a tea extract.
Claim 27
Dependent Claim
26 words
The process of claim 1 further comprising the step of desorbing caffeine from the adsorbent resin by contacting the resin with an alcohol and water mixture.
Claim 28
Dependent Claim
19 words
The process of claim 26 wherein the organic solvent in the mixture is at least about 70 weight percent.
Claim 29
Dependent Claim
19 words
The process of claim 27 wherein the organic solvent in the mixture is at least about 85 weight percent.
Claim 30
Dependent Claim
29 words
The process of claim 26 wherein a sufficient volume of regeneration effluent contacts the adsorbent resin to desorb at least about 85 percent of the caffeine from the copolymer.
Claim 31
Dependent Claim
29 words
The process of claim 29 wherein a sufficient volume of regeneration effluent contacts the adsorbent resin to desorb at least about 95 percent of the caffeine from the copolymer.
Claim 32
Dependent Claim
56 words
The process of claim 26 wherein a packed column of the adsorbent resin used for decaffeinating the liquid solution is treated prior to contact with the regeneration effluent by contacting the packed column with an effective amount of water and then backwashing the packed column to classify and expand the column and to remove particulate contaminants.
Claim 33
Dependent Claim
17 words
The process of claim 31 wherein the post-crosslinked gel copolymer is functionalized with dimethylamine, trimethylamine or dimethylethanolamine.
Claim 34
Dependent Claim
31 words
The process of claim 1 wherein the adsorbent resin removes caffeine from the liquid extract without removing up to about 17 percent of the chlorogenic acid in the liquid extract solution.
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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) | 1994-06-03 | 1994-12-03 | 1995-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-03 | 1998-12-03 | 1999-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-03 | 2002-12-03 | 2003-06-04 | $7700.00 | Window Closed / Lapsed |