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US4448599A Expired / Lapsed US ⏱️ 0.0 years remaining

Hollow spheres produced from natural zeolites

Assignee: Atlantic Richfield Co
•
Filing: 1982-03-22
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Granted: 1984-05-15
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Expires: 2002-03-22
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Abstract

Abstract A process is described for the formation of hollow glassy generally spherical particles ("microspheres") from natural mineral zeolites. A zeolite (or a mixture of zeolites) is rapidly heated to a temperature above its liquidus temperature to melt its surfaces, vaporize its combined water and cause it to expand to form the microspheres. The microspheres have diameters in the range of 1 to 500 millimeters and densities of about 0.1 to 2.0 g/cm 3 . They are useful as fillers and extenders in many materials such as plastics, and, because of their resistance to alkaline attack, are especially useful as fillers in cementitious materials.

Inventors

  • 👤 John D. Mackenzie
  • 👤 Tetsuro Horiuchi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 13:28
CPC Classifications
C; C03; C03B; C03B19/00; C03B19/10; C03B19/107; C03C; C03C1/00; Y; Y02; Y02P; Y02P40/00; Y02P40/50; Y02P40/57

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 82 words
A process for the formation of hollow glassy generally spherical particles which comprises rapidly heating natural mineral zeolite particles to a temperature above the liquidus temperature of the particles for a time sufficient to melt the surfaces of the particles and cause the combined water present in the particles to be rapidly vaporized, whereby the particles expand and form said hollow glassy particles, and the hollow glassy particles are thereafter quenched in an ambient atmosphere at a temperature below said liquidus temperature.
Claim 2
Dependent Claim 82 words
A process for the formation of hollow glassy generally spherical particles which comprises rapidly heating natural mineral zeolite particles to a temperature above the liquidus temperature of the particles for a time sufficient to melt the surfaces of the particles and cause the combined water present in the particles to be rapidly vaporized, whereby the particles expand and form said hollow glassy particles, and the hollow glassy particles are thereafter quenched in an ambient atmosphere at a temperature below said liquidus temperature.
Claim 3
Dependent Claim 18 words
A process as in claim 1 wherein said temperature is in the range of 900° to 1700° C.
Claim 4
Dependent Claim 18 words
A process as in claim 2 wherein said temperature is in the range of 1300° to 1500° C.
Claim 5
Dependent Claim 37 words
A process as in claims 1, 2 or 3 wherein said zeolite particles initially at ambient temperature are exposed to said elevated temperature for a period in the range of from about 0.001 to about 10.0 seconds.
Claim 6
Dependent Claim 28 words
A process as in claim 1 wherein said zeolite particles comprise the minerals analcime, chabazite, clinoptilolite, erionite, ferrierite, heulandite, laumontite, mordenite, natrolite, phillipsite and wairakite and mixtures thereof.
Claim 7
Dependent Claim 23 words
A process as in claim 1 wherein said zeolite particles have sizes in the range of from about 0.1 to about 100 micrometers.
Claim 8
Dependent Claim 25 words
A process as in claims 1 or 2 wherein said heating is effected while the zeolite particles fall vertically by gravity within a hollow furnace.
Claim 9
Dependent Claim 42 words
A process as in claim 7 wherein the hollow spheres are formed within a heated flame zone in a furnace containing a combustible fuel burner and after formation are conveyed out of the furnace entrained in the combustion gases from said burner.

References Cited (Backward Citations)

US2639132A Cited
US2797201A Cited
US2676892A Cited
US3030215A Cited
US3129086A Cited
US3365315A Cited
US3838998A Cited
US3794503A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-05-15 1987-11-14 1988-05-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-05-15 1991-11-14 1992-05-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-05-15 1995-11-14 1996-05-15 $7700.00 Window Closed / Lapsed

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