US4871693A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Porous cordierite ceramics
Assignee: Kanto Chemical Co Inc
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Filing: 1987-09-24
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Granted: 1989-10-03
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Expires: 2007-09-24
Abstract
Abstract New type porous cordierite ceramics having a new characteristic interconnecting open cellular structure and a hollow microspherical cordierite glass powder with a shell devoid of any pores or provided with a few or an abundance of open pores which is used as a starting material for the porous cordierite ceramics. The porous cordierite ceramics are produced by subjecting a starting solution containing an alkyl silicate, an aluminum salt and an magnesium salt optionally with other compounds in an organic or aqueous organic solvent to spray thermal decomposition to prepare the hollow microspherical cordierite glass powder, and then processing the cordierite glass powder to a shaped body after or before an optional heat treatment and firing the shaped body at a temperature below the melting point of cordierite. The porous cordierite ceramics are useful as a carrier for gas chromatography or various chemical reactions.
Inventors
- 👤 Senya Inoue
- 👤 Akira Ono
- 👤 Mikio Kobayashi
- 👤 Hiroshi Yokoo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:23
CPC Classifications
B; B01; B01J; B01J21/00; B01J21/14; B01J20/00; B01J20/02; B01J20/10; B01J20/16; B01J20/281; B01J20/282; C; C01; C01B; C01B33/00; C01B33/20; C01B33/26; C03; C03B; C03B19/00; C03B19/10; C03B19/107; C03B19/108; C03C; C03C10/00; C03C10/0036; C03C10/0045; C03C11/00; C03C11/002; C04; C04B; C04B35/00; C04B35/01; C04B35/16; C04B35/18; C04B35/195; C04B38/00; C04B38/009; C04B38/08; G; G01; G01N; G01N30/00; G01N30/02; G01N30/50; G01N30/52; G01N2030/524; G01N2030/528
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
145 words
Porous cordierite ceramics having an interconnecting open cellular structure, which have been formed by the process which comprises providing a starting solution containing in an organic or aqueous organic solvent an alkyl silicate and aluminum and magnesium salts soluble in said organic solvent in a proportion of 44-65% by weight, 25-43% by weight and 10-16% by weight in terms of SiO 2 , Al 2 O 3 and MgO, respectively, subjecting said starting solution to spray thermal decomposition in the presence of an oxidizing gas to form a hollow microspherical cordierite glass powder, processing said glass powder to a shaped body after an optional heat treatment, and thereafter firing said shaped body at a temperature above 1000° C., wherein said interconnecting open cellular structure comprises individual hollow spheres having spherical shells which are interconnected with a number of open pores existing in the spherical shells.
Claim 2
Dependent Claim
145 words
Porous cordierite ceramics having an interconnecting open cellular structure, which have been formed by the process which comprises providing a starting solution containing in an organic or aqueous organic solvent an alkyl silicate and aluminum and magnesium salts soluble in said organic solvent in a proportion of 44-65% by weight, 25-43% by weight and 10-16% by weight in terms of SiO 2 , Al 2 O 3 and MgO, respectively, subjecting said starting solution to spray thermal decomposition in the presence of an oxidizing gas to form a hollow microspherical cordierite glass powder, processing said glass powder to a shaped body after an optional heat treatment, and thereafter firing said shaped body at a temperature above 1000° C., wherein said interconnecting open cellular structure comprises individual hollow spheres having spherical shells which are interconnected with a number of open pores existing in the spherical shells.
Claim 3
Dependent Claim
37 words
Porous cordierite ceramics according to claim 1, wherein said organic solvent is selected from a lower alkanol with 1-5 carbon atoms, a dihydric or trihydric lower alcohol, a (lower alkoxy) lower alkanol and a lower dialkyl ketone.
Claim 4
Dependent Claim
29 words
Porous cordierite ceramics according to claim 1, wherein said alkyl silicate is selected from tetraalkyl silicates in which the alkyl moiety is a lower alkyl with 1-5 carbon atoms.
Claim 5
Dependent Claim
51 words
Porous cordierite ceramics according to claim 1, wherein said organic or aqueous organic solvent contains one or more metal compounds capable of affording Na 2 O, K 2 O, TiO 2 or ZrO 2 and soluble in the organic or aqueous organic solvent in an amount up to 5% by weight.
Claim 6
Dependent Claim
30 words
Porous cordierite ceramics according to claim 1, wherein said firing of the shaped body is effected at a temperature above the crystallization temperature but below the melting point of cordierite.
Claim 7
Dependent Claim
39 words
Porous cordierite ceramics according to claim 1, wherein said spray thermal decomposition is carried out by spraying the starting solution together with an oxidizing gas from a nozzle into a heated reaction zone or the flame of a burner.
Claim 8
Dependent Claim
40 words
Porous cordierite ceramics according to claim 1, wherein said processing of the glass powder to a shaped body is effected by molding, extruding, calendering, a curing-in-liquid method, a liquid drying method, a spray drying method or a freeze drying method.
Claim 9
Dependent Claim
20 words
Porous cordierite ceramics according to claim 1, wherein said heat treatment is carried out at a temperature below 950° C.
References Cited (Backward Citations)
US2797201A
Cited
US3030215A
Cited
US3347798A
Cited
US3950175A
Cited
US4021253A
Cited
US4257799A
Cited
US4367292A
Cited
US4374044A
Cited
US4547468A
Cited
US4560660A
Cited
US4698317A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-02 | 1993-04-03 | 1993-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-02 | 1997-04-03 | 1997-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-02 | 2001-04-03 | 2001-10-03 | $7700.00 | Window Closed / Lapsed |