Patent US5852088A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5852088A Expired / Lapsed US ⏱️ 0.0 years remaining

Nanoporous ceramics with catalytic functionality

Assignee: ExxonMobil Technology and Engineering Co
•
Filing: 1995-12-27
•
Granted: 1998-12-22
•
Expires: 2015-12-27
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The present invention provides for amorphous, nanoporous, catalytic metal-containing ceramic material having a surface area in excess of 70 m2/gm and characterized by a high content of open microporous cell structure wherein the micropores have a mean width of less than 20 Angstroms and wherein said microporous structure comprises a volume of greater than about 0.03 cm3/gm of the ceramic. The invention also provides for a preceramic composite intermediate composition comprising a mixture of a ceramic precursor and from about 0.5 up to about 65 wt % of an organometallic compound containing a metal of Group IB, II, III, IV, IV, V, VIB, VIIA or VIII of the Periodic Table, including rare earth metals, whose pyrolysis product in ammonia or an inert atmosphere at temperatures of up to less than about 1100 DEG C. gives rise to the nanoporous catalytic ceramics of the invention. Also provided is a process for the preparation of the nanoporous ceramics of the invention involving pyrolysis of the ceramic intermediate under controlled conditions of heating up to temperatures of less than about 1100 DEG C. to form a nanoporous ceramic product useful in catalytic and membrane separation processes.

Inventors

  • 👤 John P. Dismukes
  • 👤 Jack Wayne Johnson
  • 👤 John Stewart Bradley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 04:31
CPC Classifications
C; C04; C04B; C04B38/00; C04B38/0022; B; B01; B01J; B01J35/00; B01J35/60; B01J35/61; B01J35/613; B01J35/615; B01J35/63; B01J35/633; B01J35/64; B01J35/643; C04B2111/00; C04B2111/00474; C04B2111/00793; C04B2111/00801; C04B2111/0081

Claims Analysis

Total Claims: 46
Claim 1
Independent Claim 71 words
A preceramic composite intermediate composition comprising a mixture of a ceramic precursor oligomer or polymer having a number average molecular weight in the range of from about 200 to about 100,000 g/mole having uniformly dispersed therein from about 0.5 up to about 65 wt % of an organometallic compound containing a metal of Group IB, II, III, IV, V, VIB, VIIA or VIII of the Periodic Table, including rare earth metals.
Claim 2
Dependent Claim 71 words
A preceramic composite intermediate composition comprising a mixture of a ceramic precursor oligomer or polymer having a number average molecular weight in the range of from about 200 to about 100,000 g/mole having uniformly dispersed therein from about 0.5 up to about 65 wt % of an organometallic compound containing a metal of Group IB, II, III, IV, V, VIB, VIIA or VIII of the Periodic Table, including rare earth metals.
Claim 3
Dependent Claim 32 words
The composition of claim 1 wherein said ceramic precursor is selected from the group consisting of polysilazanes, polysiloxazanes, polycarbosilazanes, perhydropoly-silazanes, polycarbosilanes, vinylic polysilanes, amine boranes, polyphenylborazones, carboranesiloxanes, polysilastyrenes, polytitanocarbosilanes and mixtures thereof.
Claim 4
Dependent Claim 12 words
The composition of claim 2 wherein said ceramic precursor comprises a polysilazane.
Claim 5
Dependent Claim 12 words
The composition of claim 2 wherein said ceramic precursor comprises a polycarbosilane.
Claim 6
Dependent Claim 12 words
The composition of claim 2 wherein said ceramic precursor comprises a polysilastyrene.
Claim 7
Dependent Claim 34 words
The composition of claim 1 which contains from about 75 to about 99 parts by weight of said ceramic precursor and from about 1 to about 35 parts by weight of said organometallic compound.
Claim 8
Dependent Claim 39 words
The composition of claim 1 wherein said organometallic compound is selected from the group consisting of metal carbonyls, metal salts of organic or inorganic acids, metal chelates with organic ligands, organic solvent dispersible metal silicate-containing clay and metal-containing polymers.
Claim 9
Dependent Claim 16 words
The composition of claim 7 wherein said organometallic compound is a metal chelate of a beta-diketone.
Claim 10
Dependent Claim 11 words
The composition of claim 8 wherein said beta diketone is acetylacetone.
Claim 11
Dependent Claim 13 words
The composition of claim 7 wherein said organometallic compound is a metal carbonyl.
Claim 12
Dependent Claim 14 words
The composition of claim 10 wherein said carbonyl is a rare earth metal carbonyl.
Claim 13
Dependent Claim 15 words
The composition of claim 7 wherein said organometallic compound is a tetra-ammonium alkyl exchanged clay.
Claim 14
Dependent Claim 15 words
The composition of claim 7 wherein said organometallic compound is an aluminoxane or polyalazane polymer.
Claim 15
Dependent Claim 31 words
The composition of claim 1 wherein said organometallic compound contains a metal selected from the group consisting of Pt, Pd, Rh, Re, Ru, Fe, Ni, Cu, Co, Ag, Al and Ga.
Claim 16
Dependent Claim 32 words
The composition of claim 1 wherein said organometallic compound contains a metal selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y and rare earth metals.
Claim 17
Dependent Claim 14 words
The composition of claim 15 wherein said organometallic compound contains a rare earth metal.
Claim 18
Dependent Claim 188 words
A process for preparing a nanoporous ceramic product having catalytic properties and having a surface area in excess of 70 m 2 /gm and a volume of open-pore micropores, which have a mean diameter of less than 20 Angstroms, of greater than about 0.03 cm 3 /gm, comprising: a. forming an intimate mixture comprising a ceramic precursor oligomer or polymer having a number average molecular weight in the range of from about 200 to about 100,000 g/mole and from about 0.5 to about 65% by weight of an organometallic compound containing a metal of Group IB, II, III, IV, V, VIB, VIIA, or VIII of the Periodic Table, including rare earth metals; b. gradually heating said mixture in the presence of ammonia or an inert gas, with optional sequential stages with hold times at intermediate temperatures, to a maximum temperature in the range of from about 300° C. up to less than 1100° C. and over a period of total combined heating and optional hold time of from about 3 to about 50 hours to form said microporous ceramic product; and c. gradually cooling said nanoporous ceramic product.
Claim 19
Dependent Claim 188 words
A process for preparing a nanoporous ceramic product having catalytic properties and having a surface area in excess of 70 m 2 /gm and a volume of open-pore micropores, which have a mean diameter of less than 20 Angstroms, of greater than about 0.03 cm 3 /gm, comprising: a. forming an intimate mixture comprising a ceramic precursor oligomer or polymer having a number average molecular weight in the range of from about 200 to about 100,000 g/mole and from about 0.5 to about 65% by weight of an organometallic compound containing a metal of Group IB, II, III, IV, V, VIB, VIIA, or VIII of the Periodic Table, including rare earth metals; b. gradually heating said mixture in the presence of ammonia or an inert gas, with optional sequential stages with hold times at intermediate temperatures, to a maximum temperature in the range of from about 300° C. up to less than 1100° C. and over a period of total combined heating and optional hold time of from about 3 to about 50 hours to form said microporous ceramic product; and c. gradually cooling said nanoporous ceramic product.
Claim 20
Dependent Claim 32 words
The process of claim 17 wherein said ceramic precursor is selected from the group consisting of polysilazanes, polysiloxazanes, polycarbosilazanes, perhydropoly-silazanes, polycarbosilanes, vinylic polysilanes, amine boranes, polyphenylborazones, carboranesiloxanes, polysilastyrenes, polytitanocarbosilanes and mixtures thereof.
Claim 21
Dependent Claim 12 words
The process of claim 18 wherein said ceramic precursor comprises a polysilazane.
Claim 22
Dependent Claim 12 words
The process of claim 18 wherein said ceramic precursor comprises a polycarbosilane.
Claim 23
Dependent Claim 12 words
The process of claim 18 wherein said ceramic precursor comprises a polysilastyrene.
Claim 24
Dependent Claim 36 words
The process of claim 17 wherein said mixture contains from about 75 to about 99 parts by weight of said ceramic precursor and from about 1 to about 35 parts by weight of said organometallic compound.
Claim 25
Dependent Claim 39 words
The process of claim 17 wherein said organometallic compound is selected from the group consisting of metal carbonyls, metal salts of organic or inorganic acids metal chelates with organic ligands, organic solvent dispersible metal silicate--containing clay and metal-containing polymers.
Claim 26
Dependent Claim 16 words
The process of claim 23 wherein said organometallic compound is a metal chelate of a beta-diketone.
Claim 27
Dependent Claim 11 words
The process of claim 24 wherein said beta diketone is acetylacetone.
Claim 28
Dependent Claim 13 words
The process of claim 23 wherein said organometallic compound is a metal carbonyl.
Claim 29
Dependent Claim 14 words
The process of claim 26 wherein said carbonyl is a rare earth metal carbonyl.
Claim 30
Dependent Claim 15 words
The process of claim 23 wherein said organometallic compound is a tetra-ammonium alkyl exchanged clay.
Claim 31
Dependent Claim 15 words
The process of claim 23 wherein said organometallic compound is an aluminoxane or polyalazane polymer.
Claim 32
Dependent Claim 31 words
The process of claim 17 wherein said organometallic compound contains a metal selected from the group consisting of Pt, Pd, Rh, Re, Ru, Fe, Ni, Cu, Co, Ag, Al and Ga.
Claim 33
Dependent Claim 32 words
The process of claim 17 wherein said organometallic compound contains a metal selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Y and rare earth metals.
Claim 34
Dependent Claim 14 words
The process of claim 31 wherein said organometallic compound contains a rare earth metal.
Claim 35
Dependent Claim 31 words
The process of claim 17 wherein said intimate mixture is formed by forming a solution of said ceramic precursor and said organometallic compound in an organic solvent, and removing said solvent.
Claim 36
Dependent Claim 36 words
The process of claim 17 wherein said intimate mixture is formed by heating a mixture of said ceramic precursor and said organometallic compound to a temperature up to about 250° C. to form a melt mixture.
Claim 37
Dependent Claim 16 words
The process of claim 17 wherein said heating is conducted in the presence of ammonia gas.
Claim 38
Dependent Claim 71 words
The process of claim 17 wherein said mixture is heated to a maximum temperature (T max ) in the range of from about 400° C. up to less than 1100° C., said heating characterized by a rate of temperature increase between about 300° C. to 600° C., or between about 300° C. to T max where T max is less than 600° C. of less than about 5° C. per minute.
Claim 39
Dependent Claim 16 words
The process of claim 36 wherein T max ranges from about 400° C. to 1000° C.
Claim 40
Dependent Claim 15 words
The process of claim 37 wherein T max ranges from about 500° C. and 750°.
Claim 41
Dependent Claim 27 words
The process of claim 17 wherein said nanoporous ceramic product has a pore structure wherein the pores have a mean width of up to about 100 Angstroms.
Claim 42
Dependent Claim 48 words
A nanoporous ceramic product having a surface area in excess of 70 m 2 /gm and a volume of open-pore micropores, which have a mean width of less than 20 Angstroms, of greater than about 0.03 cm 3 /gm, said product prepared by the process of claim 17.
Claim 43
Dependent Claim 18 words
The ceramic product of claim 40 having a surface area in excess of about 100 m 2 /gm.
Claim 44
Dependent Claim 30 words
The ceramic product of claim 41 having a surface area in excess of about 200 m 2 /gm and a micropore volume of greater than about 0.08 cm 3 /gm.
Claim 45
Dependent Claim 13 words
The ceramic product of claim 40 in the form of a thin membrane.
Claim 46
Dependent Claim 18 words
The ceramic product of claim 40 containing from about 0.1 up to about 10% by weight of metal.

References Cited (Backward Citations)

EP0200326A1 Cited
US4833107A Cited
US4937304A Cited
US4950381A Cited
US4835207A Cited
US4891340A Cited
EP0331424A1 Cited
US4857492A Cited
US5006492A Cited
EP0376183A1 Cited
EP0389084A2 Cited
US4942145A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-12-21 2002-06-22 2002-12-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-12-21 2006-06-22 2006-12-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-12-21 2010-06-22 2010-12-22 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag