Refractory composite comprising a geopolymer and method of making a refractory composite

Patent metadata

Field	Value
Publication number	US-2016304402-A1
Application number	US-201514832484-A
Country	US
Kind code	A1
Filing date	Aug 21, 2015
Priority date	Aug 22, 2014
Publication date	Oct 20, 2016
Grant date	—

Abstract

A refractory composite comprises a geopolymer and a plurality of anisotropic refractory particles dispersed in the geopolymer at a concentration of at least about 15 vol. %. The geopolymer has a composition comprising M 2 O, Al 2 O 3 , SiO 2 and H 2 O, where M includes one or more elements selected from the group consisting of: Li, Na, K, Rb and Cs. A method of making a refractory composite comprises forming a geopolymer precursor suspension, and mixing a plurality of refractory particles into the geopolymer precursor solution while exposing the geopolymer precursor solution to vibrational energy, thereby forming a precursor composite mixture. After the mixing, the vibrational energy is removed and the precursor composite mixture is cured, thereby forming a refractory composite, which may be referred to as a geopolymer composite.

First claim

1 . A refractory composite comprising:
a geopolymer having a composition comprising M 2 O, Al 2 O 3 , SiO 2 and H 2 O, where M includes one or more elements selected from the group consisting of: Li, Na, K, Rb and Cs; and a plurality of anisotropic refractory particles dispersed in the geopolymer at a concentration of at least about 15 vol. %.

2 . The refractory composite of claim 1 , wherein the anisotropic refractory particles comprise platelets.

3 . The refractory composite of claim 1 , wherein the anisotropic refractory particles have an aspect ratio of from about 2:1 to about 100:1.

4 . The refractory composite of claim 3 , wherein the aspect ratio is from about 3:1 to about 50:1.

5 . The refractory composite of claim 1 , wherein the anisotropic refractory particles comprise a material selected from the group consisting of: alumina, titania, zirconia, silicon carbide, mullite, calcium carbonate, dolomite, granite, mica, silica, silicon oxynitride, tungsten, molybdenum, niobium, tantalum and rhenium.

6 . The refractory composite of claim 1 , wherein the concentration of the anisotropic refractory particles is up to about 70 vol. %.

7 . The refractory composite of claim 1 , wherein the anisotropic refractory particles comprise an average linear size of from about 5 microns to 500 microns.

8 . The refractory composite of claim 1 , wherein the geopolymer comprises a first molar ratio R 1 =(moles of Si+moles of Al)/(moles of M), where 1≦R 1 ≦8.

9 . The refractory composite of claim 8 , wherein 1≦R 1 ≦5.

10 . The refractory composite of claim 1 , wherein the geopolymer comprises a second molar ratio R 2 =(moles of Si)/(moles of Al), where 1≦R 2 ≦50.

11 . The refractory composite of claim 10 , wherein 1≦R 2 ≦30.

12 . The refractory composite of claim 1 , wherein the geopolymer comprises a third molar ratio R 3 =(moles of H 2 O)/(moles of Si+moles of Al), where 0.2≦R 3 ≦4.

13 . The refractory composite of claim 12 , wherein 1≦R 3 ≦3.

14 . The refractory composite of claim 1 , wherein M is the element K.

15 . The refractory composite of claim 14 , wherein the geopolymer comprises the molar relationship: K 2 O:Al 2 O 3 :4SiO 2 :11H 2 O.

16 . A structure comprising the refractory composite of claim 1 , wherein the structure is resistant to thermal shock.

17 . The structure of claim 16 being selected from the group consisting of: crucible, mold, coating, gating system component, roller, oven lining, brick, construction material, rocket nozzle and heat shield.

18 . A method of making a refractory composite, the method comprising:
forming a geopolymer precursor suspension; mixing a plurality of refractory particles into the geopolymer precursor suspension while exposing the geopolymer precursor suspension to vibrational energy, thereby forming a precursor composite mixture; and after the mixing, removing the vibrational energy and curing the precursor composite mixture, thereby forming a geopolymer composite.

19 . The method of claim 18 , further comprising, after the mixing and prior to the curing, further processing the precursor composite mixture, wherein the further processing comprises:
deforming the precursor composite mixture and/or transferring the precursor composite mixture to a substrate to form a predetermined structure, wherein the vibrational energy is applied to the precursor composite mixture during the further processing.

20 . The method of claim 19 , wherein the transferring comprises at least one of: pouring, casting, dripping, extruding, spraying, and pumping the precursor composite mixture.

21 . The method of claim 18 , wherein the refractory particles are dispersed in the geopolymer precursor suspension at a concentration sufficient to produce, when the geopolymer precursor suspension is not exposed to the vibrational energy, an apparent viscosity thereof of greater than about 100 Pa·s.

22 . The method of claim 21 , wherein the apparent viscosity is greater than about 500 Pa·s.

23 . The method of claim 18 , wherein the refractory particles comprise anisotropic refractory particles and are dispersed in the geopolymer composite at a concentration of at least about 15 vol. %.

24 . The method of claim 18 , wherein the refractory particles comprise platelets.

Assignees

• Univ Illinois

Inventors

• Kriven Waltraud M
• Kutyla Gregory

Classifications

• C04B33/131

  Inorganic additives · CPC title

• C04B2235/349

  Clays, e.g. bentonites, smectites such as montmorillonite, vermiculites or kaolines, e.g. illite, talc or sepiolite · CPC title

• C04B2235/5292

  Flakes, platelets or plates · CPC title

• C04B2235/3427

  Silicates other than clay, e.g. water glass · CPC title

• C04B33/36 Primary

  Reinforced clay-wares · CPC title