Dimensionally stable geopolymer composition and method

Patent metadata

Field	Value
Publication number	US-9890082-B2
Application number	US-201313842100-A
Country	US
Kind code	B2
Filing date	Mar 15, 2013
Priority date	Apr 27, 2012
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

A method for making geopolymer cementitious binder compositions for cementitious products such as concrete, precast construction elements and panels, mortar, patching materials for road repairs and other repair materials, and the like is disclosed. The geopolymer cementitious compositions of some embodiments are made by mixing a synergistic mixture of thermally activated aluminosilicate mineral, calcium sulfoaluminate cement, a calcium sulfate and a chemical activator with water.

First claim

What is claimed is:

1. An aluminosilicate geopolymer composition comprising the reaction product of:
a cementitious reactive material comprising:
about 33 to about 97% by weight a thermally activated aluminosilicate mineral comprising Class C fly ash,
about 1 to about 43% by weight a calcium sulfoaluminate cement,
about 1 to about 40% by weight a calcium sulfate selected from the group consisting of calcium sulfate dihydrate, calcium sulfate hemihydrate, anhydrous calcium sulfate and mixtures thereof; and

a chemical activator in an amount equal to about 1.0 to about 6.0% by weight of the cementitious reactive material, the chemical activator selected from at least one member of the group consisting of alkali metal citrates; and
water,
wherein the calcium sulfate has an average particle size from about 1 to about 100 microns.

2. The aluminosilicate geopolymer composition of claim 1 , wherein the cementitious reactive material comprises
about 33 to about 97% by weight Class C fly ash,
about 1 to about 40% by weight said calcium sulfoaluminate cement,
about 1 to about 40% by weight said calcium sulfate
wherein the chemical activator is selected from at least one member of the group consisting of an potassium citrate and sodium citrate.

3. The composition of claim 1 , wherein the chemical activator is selected from at least one member of the group consisting of sodium citrate and potassium citrate.

4. The composition of claim 1 , wherein the composition has an absence of Portland cement.

5. The composition of claim 1 , wherein the amounts of the chemical activator and calcium sulfate relative to the amounts of thermally activated aluminosilicate mineral and calcium sulfoaluminate cement are effective to cause the reaction product to set in about 120 minutes or less after mixing with water.

6. The composition of claim 1 , wherein the cementitious reactive material comprises:
about 41 to about 67% by weight Class C fly ash,
about 18 to about 43% by weight calcium sulfoaluminate cement, and
about 4 to about 36% by weight calcium sulfate;

wherein the amount of chemical activator equals about 2 to about 5.0% by weight of the cementitious reactive powder, wherein the chemical activator is selected from at least one member of the group consisting of sodium citrate and potassium citrate.

7. The composition of claim 6 , wherein the amount of calcium sulfoaluminate cement relative to the amounts of chemical activator, calcium sulfate and thermally activated aluminosilicate mineral is effective to cause the reaction product to set in about 120 minutes or less after mixing with water.

8. The composition of claim 1 , wherein the amount of calcium sulfoaluminate cement, calcium sulfate and chemical activator relative to the amount of thermally activated aluminosilicate mineral is effective to limit shrinkage of the composition to less than about 0.3%.

9. The composition of claim 1 , wherein the chemical activator is present in an amount equal to about 1.25 to 4.00% by weight based on total weight of the cementitious reactive powder; wherein the chemical activator is selected from at least one member of the group consisting of sodium citrate and potassium citrate.

10. The composition of claim 1 , wherein the reaction product is formed from
the water,
the cementitious reactive material comprising
about 60% to about 90% by weight said thermally activated aluminosilicate mineral comprising Class C fly ash;
about 4% to about 35% by weight said calcium sulfoaluminate cement, and
about 4.0% to about 15% by weight said calcium sulfate, and

the chemical activator, wherein the amount of chemical activator equals about 1.25 to 4.00% by weight of the cementitious reactive material.

11. The composition of claim 1 , wherein the reaction product is formed from
the water;
the cementitious reactive material comprising
about 60% to about 85% by weight of the thermally activated mineral comprising Class C fly ash,
about 8% to about 30% by weight calcium sulfoaluminate cement, and
about 4.0% to about 15% by weight calcium sulfate, and

the chemical activator, wherein the amount of chemical activator equals about 1.5 to 3.00% by weight of the cementitious reactive material.

12. The composition of claim 1 , further comprising lithium carbonate.

13. The composition of claim 1 , having a 4-hour compressive strength from about 1000 psi (6.9 MPa) to about 2500 psi (17.2 MPa).

14. The composition of claim 1 , having a 24-hour compressive strength about 1500 psi (10.3 MPa) to about 3500 psi (24.1 MPa).

15. The composition of claim 1 , having a 28-day compressive strength from about 3500 psi (24.1 MPa) to about 10000 psi (69 MPa).

16. The composition of claim 1 , having a water saturated compressive strength at 28-days from about 3500 psi (24.1 MPa) to about 10000 psi (69 MPa).

17. The composition of claim 1 , wherein the calcium sulfate comprises calcium sulfate hemihydrate.

18. The composition of claim 1 , wherein the calcium sulfate comprises calcium sulfate dehydrate.

19. The composition of claim 1 , wherein the calcium sulfate comprises anhydrous calcium sulfate.

20. The composition of claim 1 , wherein the composition has a tensile bonding strength to substrates in excess of 200 psi.

21. The composition of claim 1 , wherein the composition further comprises a filler.

22. The composition of claim 1 , wherein the reaction product results from an exothermic reaction in a water slurry, wherein the amount of calcium sulfoaluminate cement, calcium sulfate and chemical activator relative to the amount of thermally activated aluminosilicate mineral is effective to limit the maximum slurry temperature rise to about 50° F. or less, wherein the amount of chemical activator equals about 1.25 to about 4% by weight of the cementitious reactive material.

23. The composition of claim 22 , wherein the maximum slurry temperature rise is limited to less than about 40° F.

24. The composition of claim 22 ,
wherein the cementitious reactive material comprises:
about 41 to about 67% by weight said thermally activated aluminosilicate mineral comprising Class C fly ash,
about 18 to about 43% by weight said calcium sulfoaluminate cement, and
about 4 to about 36% by weight said calcium sulfate,

wherein the amount of the chemical activator equals about 2 to about 5.0% by weight of the cementitious reactive material.

25. The composition of claim 1 , wherein the weight ratio of the mixture to water is less than about 0.4.

26. The composition of claim 1 , wherein the weight ratio of the mixture to water is less than about 0.3.

27. A settable mixture for forming an aluminosilicate geopolymer composition when reacted in water, comprising:
a cementitious reactive material comprising:
about 33 to about 97% by weight of a thermally activated aluminosilicate mineral comprising Class C fly ash;
about 1 to about 43% by weight of a calcium sulfoaluminate cement,
about 1 to about 40% by weight of a calcium sulfate selected from the group consisting of calcium sulfate dihydrate, calcium sulfate hemihydrate, anhydrous calcium sulfate and mixtures thereof; and

a chemical activator selected from at least one member of the group consisting of alkali metal citrates, wherein the chemical activator is present in an amount equal to about 1.0 to about 6.0% by weight of the cementitious reactive material

Assignees

• United States Gypsum Co

Inventors

• Dubey Ashish

Classifications

• C04B2111/00586

  Roofing materials · CPC title

• C04B2111/00482

  Coating or impregnation materials · CPC title

• C04B12/005 Primary

  Geopolymer cements, e.g. reaction products of aluminosilicates with alkali metal hydroxides or silicates · CPC title

• C04B28/18

  containing mixtures of the silica-lime type · CPC title

• C04B2111/0075

  for road construction · CPC title