US4999330A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High-density adsorbent and method of producing same
Assignee: UNIVERSITE DU QUEBEC A TROIS-RIVIERS QUEBECOISE D'INITIATIVES PETROLIERES Ste
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Filing: 1989-02-21
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Granted: 1991-03-12
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Expires: 2009-02-21
Abstract
Abstract The invention is concerned with a high-density adsorbent comprising a compacted mass of high surface area carbon particles bound together with a binder and defining a network of substantially unobstructed micropores, the mass of carbon particles having been compacted under a pressure sufficient to cause a reduction of about 50 to about 200% in bulk volume of the mass and a corresponding increase of about 50 to about 200% in density, thereby providing a gas storage capacity increase of about 20 to about 100% over that of the high surface area carbon particles in loose or uncompacted form. The high-density adsorbent according to the invention is particularly useful in adsorption storage systems for low-pressure storage of compressed natural gas.
Inventors
- 👤 Tapan K. Bose
- 👤 Richard Chahine
- 👤 Jean-Marie St-Arnaud
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:57
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/20; Y; Y10; Y10S; Y10S502/00; Y10S502/526
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
183 words
A method of producing a dimensionally stable, high-density adsorbent, comprising the steps of: a) mixing high surface area carbon particles with a solution of a binder in a solvent to form a slurry and thereby wet each particle of carbon with the solution of binder, said binder being selected from the group consisting of methylcellulose and a polyvinyl alcohol; b) removing the solvent from the slurry prepared in step (a) to obtain particles of carbon coated with a film of the binder; and c) compacting the binder-coated particles of carbon under pressure of about 140 to about 600 MPA to provide a compacted mass of high surface area carbon particles bound together and defining a network of substantially to cause a reduction of about 50 to about 200% in bulk volume of the mass and a corresponding increase of about 50 to about 200% in density, thereby obtaining an adsorbent capable of withstanding powdering when subjected to vibration and exhibiting a gas storage capacity increase of about 20 to about 100% over that of the high surface area carbon particles in loose form.
Claim 2
Independent Claim
183 words
A method of producing a dimensionally stable, high-density adsorbent, comprising the steps of: a) mixing high surface area carbon particles with a solution of a binder in a solvent to form a slurry and thereby wet each particle of carbon with the solution of binder, said binder being selected from the group consisting of methylcellulose and a polyvinyl alcohol; b) removing the solvent from the slurry prepared in step (a) to obtain particles of carbon coated with a film of the binder; and c) compacting the binder-coated particles of carbon under pressure of about 140 to about 600 MPA to provide a compacted mass of high surface area carbon particles bound together and defining a network of substantially to cause a reduction of about 50 to about 200% in bulk volume of the mass and a corresponding increase of about 50 to about 200% in density, thereby obtaining an adsorbent capable of withstanding powdering when subjected to vibration and exhibiting a gas storage capacity increase of about 20 to about 100% over that of the high surface area carbon particles in loose form.
Claim 3
Dependent Claim
40 words
A method as claimed in claim 1, wherein prior to mixing said carbon particles with said solution of binder, said carbon particles are dispersed in said solvent to wet same and thereby fill pores in the particles with said solvent.
Claim 4
Dependent Claim
29 words
A method as claimed in claim 1, wherein removal of the solvent from the slurry is effected by heating said slurry under agitation to cause evaporation of said solvent.
Claim 5
Dependent Claim
32 words
A method as claimed in claim 1, wherein said binder is used in an amount of about 1 to about 10% by weight, based on the total weight of the adsorbent composition.
Claim 6
Dependent Claim
12 words
A method as claimed in claim 1, wherein said binder is methylcellulose.
Claim 7
Dependent Claim
24 words
A method as claimed in claim 5, wherein said methylcellulose has a viscosity of about 4,000 centipoises, calculated as a 2% solution in water.
Claim 8
Dependent Claim
14 words
A method as claimed in claim 1, wherein said binder is a polyvinyl alcohol.
Claim 9
Dependent Claim
44 words
A method as claimed in claim 7, wherein in step (c) the compacted particles are heated at a temperature and over a period of time such as to cause uniform melting of said polyvinyl alcohol throughout the compacted mass, while maintaining the compaction pressure.
Claim 10
Dependent Claim
24 words
A method as claimed in claim 8, wherein the compacted particles are heated at or slightly above the melting temperature of said polyvinyl alcohol.
Claim 11
Dependent Claim
35 words
A method as claimed in claim 8, wherein the compacted particles are heated to said temperature at a heating rate such as to avoid temperature gradients in the compacted mass and thereby prevent surface cracking.
Claim 12
Dependent Claim
26 words
A method as claimed in claim 9, wherein said polyvinyl alcohol has a molecular weight of about 125,000 and a melting point of about 200° C.
Claim 13
Dependent Claim
28 words
A method as claimed in claim 11, wherein the polyvinyl alcohol coated carbon particles are heated at a temperature of about 220° C., while being maintained under pressure.
Claim 14
Dependent Claim
33 words
A method as claimed in claim 7, wherein said polyvinyl alcohol is used in an amount of about 1 to about 5% by weight, based on the total weight of the adsorbent composition.
Claim 15
Dependent Claim
21 words
A method as claimed in claim 13, wherein said polyvinyl alcohol is used in an amount of about 2% by weight.
Claim 16
Dependent Claim
45 words
A method as claimed in claim 7, wherein the adsorbent thus obtained is subjected to a heat treatment at a temperature above the melting point of the polyvinyl alcohol to cause partial pyrolysis of said alcohol and evaporation of any solvent retained by said adsorbent.
Claim 17
Dependent Claim
24 words
A method as claimed in claim 15, wherein said heat treatment is carried out while holding the adsorbent under confinement to prevent swelling thereof.
Claim 18
Dependent Claim
34 words
A method as claimed in claim 15, wherein said polyvinyl alcohol has a melting point of about 200° C. and wherein said heat treatment is carried out at a temperature of about 300° C.
Claim 19
Independent Claim
154 words
A method of producing a dimensionally stable, high-density adsorbent, comprising the steps of: a) a mixing high surface area carbon particles in the form of a powder with a solution of a binder comprising a polyvinyl alcohol in a solvent to form a slurry and thereby wet each particle of carbon with the solution of binder; b) removing the solvent from the slurry prepared in step (a) to obtain particles of carbon coated with a film of the binder; and c) forming the binder coated particles of carbon into a shaped product by compacting the particles under a pressure of from about 140 MPa to about 600 MPa to cause binding of the carbon particles together without substantial obstruction of micropores defined in the particles, thereby obtaining an adsorbent capable of withstanding powdering when subjected to vibration and having a density substantially greater than that of the high surface area carbon in particulate form.
Claim 20
Independent Claim
154 words
A method of producing a dimensionally stable, high-density adsorbent, comprising the steps of: a) a mixing high surface area carbon particles in the form of a powder with a solution of a binder comprising a polyvinyl alcohol in a solvent to form a slurry and thereby wet each particle of carbon with the solution of binder; b) removing the solvent from the slurry prepared in step (a) to obtain particles of carbon coated with a film of the binder; and c) forming the binder coated particles of carbon into a shaped product by compacting the particles under a pressure of from about 140 MPa to about 600 MPa to cause binding of the carbon particles together without substantial obstruction of micropores defined in the particles, thereby obtaining an adsorbent capable of withstanding powdering when subjected to vibration and having a density substantially greater than that of the high surface area carbon in particulate form.
Claim 21
Dependent Claim
36 words
A dimensionally stable, high-density adsorbent comprising a compacted mass of high surface area carbon particles bound together with a binder and defining a network of substantially unobstructed micropores prepared according to the process of claim 1.
Claim 22
Dependent Claim
27 words
A high-density adsorbent as claimed in claim 19, wherein said binder is methylcellulose having a viscosity of about 4,000 centipoises, calculated as a 2% solution in water.
Claim 23
Dependent Claim
30 words
A high-density adsorbent as claimed in claim 20, wherein said methylcellulose is present in a proportion of about 10% by weight, based on the total weight of the adsorbent composition.
Claim 24
Dependent Claim
31 words
A high-density adsorbent as claimed in claim 19, wherein said binder is a polyvinyl alcohol having a molecular weight of about 125,000 and a melting point of about pb 200° C.
Claim 25
Dependent Claim
34 words
A high-density adsorbent as claimed in claim 22, wherein said polyvinyl alcohol is present in a proportion of about 1 to about 5% by weight, based on the total weight of the adsorbent composition.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-03-11 | 1994-09-10 | 1995-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-03-11 | 1998-09-10 | 1999-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-03-11 | 2002-09-10 | 2003-03-12 | $7700.00 | Window Closed / Lapsed |