High strength pozzolan foam materials and methods of making the same

• US 8,057,594 B2
• Filed: 06/19/2008
• Issued: 11/15/2011
• Est. Priority Date: 06/19/2007
• Status: Expired due to Fees

• Current Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Original Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Inventors: Biju-Duval, Paul, Doyoyo, Mulalo
• Primary Examiner(s): GREEN, ANTHONY J
• Application Number:
  US12/665,578
• Publication Number:
  US 20110146538A1
• Time in Patent Office: 1,244 Days
• Field of Search: 106/672, 106/679, 106/705, 106/708, 106/677, 106/681, 106/790, 106/811
• US Class Current: 106/679
• CPC Class Codes: C04B 12/04 Alkali metal or ammonium silicate cements ; Alkyl silicate cements; Silica sol cements; Soluble silicate cements alkali metal silicates per se, their preparation C01B33/32; ammonium silicates per se, their preparation C01C1/00
• CPC Class Codes: C04B 14/06 Quartz; Sand
• CPC Class Codes: C04B 14/28 of calcium
• CPC Class Codes: C04B 14/361 Soil, e.g. laterite
• CPC Class Codes: C04B 14/365 Gypsum synthetic gypsum C04B18/0445, C04B18/064
• CPC Class Codes: C04B 18/082 Cenospheres
• CPC Class Codes: C04B 2103/0088 Compounds chosen for their latent hydraulic characteristics, e.g. pozzuolanes
• CPC Class Codes: C04B 2103/54 Pigments; Dyes
• CPC Class Codes: C04B 2103/65 Water proofers or repellants
• CPC Class Codes: C04B 2111/2046 Shock-absorbing materials
• CPC Class Codes: C04B 2111/28 Fire resistance, i.e. materials resistant to accidental fires or high temperatures
• CPC Class Codes: C04B 22/062 of the alkali or alkaline-earth metals
• CPC Class Codes: C04B 22/064 of the alkaline-earth metals
• CPC Class Codes: C04B 22/066 Magnesia; Magnesium hydroxide
• CPC Class Codes: C04B 22/16 containing phosphorus in the anion, e.g. phosphates
• CPC Class Codes: C04B 22/165 Acids
• CPC Class Codes: C04B 24/085 Higher fatty acids
• CPC Class Codes: C04B 24/42 Organo-silicon compounds
• CPC Class Codes: C04B 26/32 containing silicon
• CPC Class Codes: C04B 28/26 Silicates of the alkali metals
• CPC Class Codes: C04B 38/08 : by adding porous substances
• CPC Class Codes: C04B 38/10 : by using foaming agents C04B38/02 takes precedenceor by using mechanical means, e.g. adding preformed foam
• CPC Class Codes: C04B 40/0263 : Hardening promoted by a rise in temperature C04B40/024 takes precedence
• CPC Class Codes: C04B 7/02 : Portland cement
• CPC Class Codes: F16L 59/028 : Composition or method of fixing a thermally insulating material
• CPC Class Codes: F17C 11/00 : Use of gas-solvents or gas-sorbents in vessels absorbing compositions for acetylene C10L3/04; absorbing compositions for hydrogen C01B3/0005
• CPC Class Codes: F17C 11/005 : for hydrogen
• CPC Class Codes: F17C 11/007 : for hydrocarbon gases, such as methane or natural gas, propane, butane or mixtures thereof [LPG]
• CPC Class Codes: Y02W 30/91 : Use of waste materials as fillers for mortars or concrete

Abstract

The various embodiments of the present invention relate generally to high strength foam materials and methods of making the same. More particularly, various embodiments of the present invention relate to high strength foam materials comprising pozzolans, such as cenospheres derived from fly ash. An embodiment of the present invention comprises, a pozzolan foam material comprising a pozzolan, an alkali, a silicate, and an organosilicon compound. Various embodiments of the present invention are directed to strong, lightweight materials that are environmentally-friendly and can be economically manufactured.

Claims

1. A pozzolan foam material, comprising:

a pozzolan in an amount ranging from about 50% to about 95%,

an organosilicon compound in an amount less than about 8 mg/ml,

an alkali hydroxide having a concentration ranging from 1M to about 2.5M, and

a silicate in an amount ranging from about 1% to about 9%.

2. The pozzolan foam material of claim 1, wherein the pozzolan comprises a plurality of cenospheres.

3. The pozzolan foam material of claim 1, wherein the organosilicon compound comprises dimethylsiloxane.

4. The pozzolan foam material of claim 1, wherein the pozzolan foam material comprises a foam-induced porosity of about 0% to about 30%.

5. The pozzolan foam material of claim 1, wherein the alkali hydroxide comprises one or more of sodium hydroxide, calcium hydroxide, pottassium hydroxide, and magnesium hydroxide.

6. The pozzolan foam material of claim 1, wherein the silicate comprises sodium silicate.

7. The pozzolan foam material of claim 1, further comprising a hydrophobic compound selected from the group consisting of lipids, waxes, oils, aliphatic compounds, acyclic compounds, cyclic compounds, aromatic compounds, alkanes, paraffins, alkenes, olefins, alkynes, polymers, esters, ethers, ketones, aldehydes, alcohols, alkyl halides, nitriles, thiols, fatty acids, and combinations thereof.

8. The pozzolan foam material of claim 7, wherein the hydrophobic compound is a cooking oil.

9. The pozzolan foam material of claim 1, further comprising a phosphorous containing compound.

10. A pozzolan foam material, comprising:

a plurality of cenospheres in an amount ranging from about 50% to about 95%, sodium hydroxide having a concentration ranging from about 1 M to about 2.5 M, sodium silicate in an amount ranging from about 1% to about 9%, and dimethylsiloxane in an amount less than about 8 mg/ml.

11. The pozzolan foam material of claim 10, wherein the plurality of cenospheres have an average longest dimension of less than about 5 micrometers to about 500 micrometers.

12. The pozzolan foam material of claim 10, wherein the pozzolan foam material has a compressive strength of greater than about 3 MPa.

13. A method of making a pozzolan foam material, comprising:

admixing a pozzolan in an amount ranging from about 50% to about 95%, an alkali hydroxide having a concentration ranging from 1M to about 2.5M, a silicate in an amount ranging from about 1% to about 9%, and an organosilicon compound in an amount ranging from less than about 8 mg/ml to form a mixture; and

curing the mixture to form a pozzolan foam material.

14. The method of making a pozzolan foam material of claim 13, wherein curing the mixture to form a pozzolan foam material comprises heating the mixture to temperatures of about 90°

C. to about 130°

C. for about 15 hours to about 28 hours.

15. The method of making a pozzolan foam material of claim 13, wherein curing the mixture to form a pozzolan foam material comprises heating the mixture to temperatures of about 100°

C. for about 20 hours.

16. The method of making a pozzolan foam material of claim 13, further comprising prior to step curing the mixture to form a pozzolan foam material, forming the mixture into an article, wherein the step of curing the mixture to form a pozzolan foam material comprises curing the article to form an article comprising a pozzolan foam material.

17. The method of making a pozzolan foam material of claim 13, wherein admixing a pozzolan, an alkali hydroxide, a silicate, and an organosilicon compound to form a mixture further comprises admixing a hydrophobic compound.

18. The method of making a pozzolan foam material of claim 13, wherein admixing a pozzolan, an alkali hydroxide, a silicate, and an organosilicon compound to form a mixture further comprises admixing a phosphorous containing compound.