US4940685A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ceric oxide particulates having a stable specific surface and a process for their preparation
Assignee: Rhone Poulenc Specialites Chimiques
•
Filing: 1986-07-03
•
Granted: 1990-07-10
•
Expires: 2006-07-03
Abstract
Abstract A ceric oxide composition, the specific surface of which remains essentially stable at elevated temperatures and which is thus well adopted for purposes of catalysis, is comprised of a plurality of solid, porous, finely divided ceric oxide particulates, said ceric oxide particulates advantageously having an effective amount of at least one oxide of another metallic element A intimately dispersed therein as to essentially prevent the coalescence of the micropores thereof.
Inventors
- 👤 Guy-Noel Sauvion
- 👤 Jack Caillod
- 👤 Claire Gourlaouen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:03
CPC Classifications
B; B82; B82Y; B82Y30/00; B01; B01J; B01J23/00; B01J23/10; B01J23/12; C; C01; C01F; C01F17/00; C01F17/20; C01F17/206; C01F17/224; C01F17/229; C01F17/235; C01F17/30; C01F17/32; C01P; C01P2004/00; C01P2004/60; C01P2004/64; C01P2006/00; C01P2006/12; C01P2006/13
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
123 words
A ceric oxide-based composition, the specific surface of which remains essentially stable at elevated temperatures, which composition includes a carrier comprising a plurality of solid, porous, finely divided ceric oxide particulates, said ceric oxide particulates of said carrier having intimately dispersed therein an effective amount of at least one oxide of a metallic element A comprising silicon, zirconium, or thorium, said ceric oxide particulates having been shaped and calcined; wherein the amount of the at least one oxide of said metallic element A comprises from about 1 to about 20% by weight of said ceric oxide particulates and wherein the specific surface area of said composition is greater than the specific surface area of said ceric oxide particulates without said metallic element A.
Claim 2
Dependent Claim
123 words
A ceric oxide-based composition, the specific surface of which remains essentially stable at elevated temperatures, which composition includes a carrier comprising a plurality of solid, porous, finely divided ceric oxide particulates, said ceric oxide particulates of said carrier having intimately dispersed therein an effective amount of at least one oxide of a metallic element A comprising silicon, zirconium, or thorium, said ceric oxide particulates having been shaped and calcined; wherein the amount of the at least one oxide of said metallic element A comprises from about 1 to about 20% by weight of said ceric oxide particulates and wherein the specific surface area of said composition is greater than the specific surface area of said ceric oxide particulates without said metallic element A.
Claim 3
Dependent Claim
33 words
The composition as defined by claim 1, wherein the amount of the at least one oxide of said metallic element A comprises from 1 to 5% by weight of said ceric oxide particulates.
Claim 4
Dependent Claim
15 words
The composition as defined by claim 1, comprising an agglomeration of said ceric oxide particulates.
Claim 5
Dependent Claim
35 words
A process for the preparation of the composition as defined by claim 1, comprising intimately dispersing the at least one oxide of said metallic element A within the pore volume of said ceric oxide particulates.
Claim 6
Dependent Claim
36 words
The process as defined by claim 4, comprising impregnating said ceric oxide particulates with a solution of a precursor of said at least one metal A oxide, and converting said precursor into the oxide form thereof.
Claim 7
Dependent Claim
14 words
The process as defined by claim 5, comprising dry impregnating said ceric oxide particulates.
Claim 8
Dependent Claim
18 words
The process as defined by claim 5, said precursor comprising zirconyl sulfate, zirconyl nitrate, or a zirconium/fluorine complex.
Claim 9
Dependent Claim
23 words
The process as defined by claim 5, comprising drying said impregnated ceric oxide particulates at a temperature of from 80° to 300° C.
Claim 10
Dependent Claim
23 words
The process as defined by claim 5, comprising drying said impregnated ceric oxide particulates at a temperature of from 100° to 150° C.
Claim 11
Dependent Claim
19 words
The process as defined by claim 8, wherein said drying is carried out for from 1 to 24 hours.
Claim 12
Dependent Claim
23 words
The process as defined by claim 8, comprising calcining said dried ceric oxide particulates at a temperature of from 400° to 1000° C.
Claim 13
Dependent Claim
17 words
The process as defined by claim 8, said temperature of calcination ranging from 600° to 900° C.
Claim 14
Dependent Claim
19 words
The process as defined by claim 8, wherein said calcination is carried out for from 1 to 24 hours.
Claim 15
Dependent Claim
19 words
The process as defined by claim 13, wherein said calcination is carried out for from 4 to 10 hours.
Claim 16
Dependent Claim
93 words
A process for the preparation of the composition as defined by claim 1, comprising (i) introducing a precursor of said at least one metal A oxide into an aqueous colloidal dispersion of a cerium (IV) compound, (ii) destabilizing the resulting dispersion by adding a basic material thereto, and whereby said ceric oxide particulates precipitate thereof, (iii) separating the precipitate thus formed, and (iv) heat treating said separated precipitate at a first temperature sufficient to dry said precipitate, followed by calcining said precipitate at a second temperature sufficient to obtain a desired specific surface.
Claim 17
Dependent Claim
22 words
The process as defined by claim 15, said precursor comprising a quaternary ammonium silicate, zirconyl nitrate or sulfate, or a zirconium/fluorine complex.
Claim 18
Dependent Claim
77 words
The process as defined by claim 15, said aqueous colloidal dispersion of a cerium (IV) compound comprising a dispersion, in water, of a cerium (IV) compound having the following general formula (I): Ce (M).sub.x (OH).sub.y (NO.sub.3).sub.z.nH.sub.2 O (I) wherein M is an alkali metal or a quaternary ammonium radical, x ranges from 0 to 0.2, z ranges from 0 to 0.7, y is such that y =4 -z +x, and n ranges from 0 to about 20.
Claim 19
Dependent Claim
24 words
The process as defined by claim 17, the concentration of said cerium (IV) compound in said colloidal dispersion ranging from 0.1 to 2.0 moles/liter.
Claim 20
Dependent Claim
32 words
The process as defined by claim 17, comprising dispersing in water a cerium (IV) compound prepared by hydrolysis in an acidic medium of an aqueous solution of a salt of cerium (IV).
Claim 21
Dependent Claim
19 words
The process as defined by claim 15, said basic material having a normality ranging from 5 to 10 N.
Claim 22
Dependent Claim
17 words
The process as defined by claim 15, the ultimate dispersion having a pH of greater than 7.
Claim 23
Dependent Claim
14 words
The process as defined by claim 21, said pH ranging from 9 to 10.
Claim 24
Dependent Claim
30 words
The process as defined by claim 15, comprising adding the base at a rate of from 0.1 to 5 moles of OH - per mole of cerium (IV) per hour.
Claim 25
Dependent Claim
29 words
The process as defined by claim 15, comprising drying said precipitate and calcining same at a temperature of from 400° to 1000° C. for from 1 to 24 hours.
Claim 26
Dependent Claim
23 words
The process as defined in claim 15, said basic material comprising an aqueous solution of ammonia, sodium or potassium hydroxide, or gaseous ammonia.
Claim 27
Dependent Claim
12 words
A catalyst comprising the ceric oxide composition as defined by claim 1.
Claim 28
Dependent Claim
26 words
A catalyst comprising a support member having an active catalytic phase deposited thereon, said active phase comprising the ceric oxide composition as defined by claim 1.
References Cited (Backward Citations)
US3752774A
Cited
US3830756A
Cited
US4062810A
Cited
US4231893A
Cited
JPS5626547A
Cited
JPS5763133A
Cited
US4606847A
Cited
JPS58114730A
Cited
US4490567A
Cited
US4510267A
Cited
US4581343A
Cited
US4663137A
Cited
US4585752A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-07-09 | 1994-01-08 | 1994-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-09 | 1998-01-08 | 1998-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-09 | 2002-01-08 | 2002-07-10 | $7700.00 | Window Closed / Lapsed |