Synthetic pozzolans

Patent metadata

Field	Value
Publication number	US-11731906-B2
Application number	US-202016854367-A
Country	US
Kind code	B2
Filing date	Apr 21, 2020
Priority date	May 5, 2016
Publication date	Aug 22, 2023
Grant date	Aug 22, 2023

Abstract

Synthetic pozzolans are produced using local materials to provide a cementitious material that is uniform in chemistry and properties independent of the location where the materials are obtained. Two methods of production are described. One is a high temperature process in which materials are processed in a semi-molten or molten state. The second process is a low temperature aqueous process.

First claim

What is claimed is:

1. A method of forming a cured cementitious material, the method comprising:
forming a synthetic calcium silicate cement from precursor materials, the synthetic calcium silicate cement comprising at least 10% by mass of an amorphous phase,
wherein forming the synthetic calcium silicate cement from precursor materials comprises:
selecting one or more precursor raw materials;
blending said one or more precursor raw materials to obtain a blended precursor composition; and
(i) heating said blended precursor composition to a temperature between about 800° C. to about 1400° C. for a time sufficient to react said blended precursor composition, or (ii) performing an aqueous reaction on the blended precursor composition;

adding the synthetic calcium silicate cement to a hydraulic cement to form a mixture, the mixture comprising 10% by mass or more of total solids of the synthetic calcium silicate cement; and
curing the mixture, the curing comprising reacting the synthetic calcium silicate cement and the hydraulic cement.

2. The method of claim 1 , wherein the amorphous phase comprises one or more of siliceous, aluminosiliceous, aluminous material, calcium-aluminum-iron-magnesium-silicate, calcium-silicate.

3. The method of claim 1 , wherein the synthetic calcium silicate cement further comprising crystalline phases such as wollastonite, pseudowollastonite, rankinite, belite, and melilite.

4. The method of claim 1 , wherein the synthetic calcium silicate cement comprises at least 30% by mass of the amorphous phase.

5. The method of claim 1 , wherein the synthetic calcium silicate cement comprises at least 70% by mass of the amorphous phase.

6. The method of claim 1 , wherein the precursor materials comprise calcium silicate.

7. The method of claim 1 , further comprising reacting the synthetic calcium silicate cement with CO 2 to form amorphous SiO 2 and CaCO 3 .

8. The method of claim 1 , wherein the reaction comprises reacting the amorphous phase of the synthetic calcium silicate cement with the hydraulic cement in the presence of water.

9. The method of claim 1 , wherein the reacting of the synthetic calcium silicate cement and the hydraulic cement in the presence of water produces a calcium silicate hydrate compound as a reaction product.

10. The method of claim 7 , wherein Si ions from the amorphous SiO 2 participate in a pozzolanic reaction between the synthetic calcium silicate cement and the hydraulic cement.

11. The method of claim 1 , wherein the mixture comprising 30% or more by mass of total solids of the synthetic calcium silicate cement.

12. The method of claim 11 , wherein the mixture comprising 40% or more by mass of total solids of the synthetic calcium silicate cement.

13. The method of claim 1 , further comprising adding aggregates to the mixture.

14. The method of claim 1 , further comprising adding water to the mixture.

15. The method of claim 1 , further comprising adding at least one admixture to the mixture.

16. The method of claim 1 , wherein the hydraulic cement comprises Ordinary Portland Cement.

17. A method forming a cured cementitious material, the method comprising:
forming a synthetic calcium silicate cement from precursor materials, the synthetic calcium silicate cement comprising at least 10% by mass of an amorphous phase,
wherein forming the synthetic calcium silicate cement from precursor materials further comprises analyzing the chemical compositions of said one or more precursor raw materials;

adding the synthetic calcium silicate cement to a hydraulic cement to form a mixture, the mixture comprising 10% by mass or more of total solids of the synthetic calcium silicate cement; and
curing the mixture, the curing comprising reacting the synthetic calcium silicate cement and the hydraulic cement.

18. A method of forming a cured cementitious material, the method comprising:
forming a synthetic calcium silicate cement from a blend of precursor materials, the synthetic calcium silicate cement comprising at least 10% by mass of an amorphous phase,
wherein a ratio of Ca to the sum of Al, Fe, Mg, and Si of the blend of precursor materials is 0.5-1.0,

adding the synthetic calcium silicate cement to a hydraulic cement to form a mixture, the mixture comprising 10% by mass or more of total solids of the synthetic calcium silicate cement; and
curing the mixture, the curing comprising reacting the synthetic calcium silicate cement and the hydraulic cement.

Assignees

• Solidia Technologies Inc

Inventors

• Atakan Vahit
• Quinn Sean
• Sahu Sadananda
• Tas Ahmet Cuneyt

Classifications

• C04B28/188 Primary

  the Ca-silicates being present in the starting mixture · CPC title

• C01B33/26 Primary

  Aluminium-containing silicates {, i.e. silico-aluminates} · CPC title

• C04B7/12

  Natural pozzuolanas; Natural pozzuolana cements; {Artificial pozzuolanas or artificial pozzuolana cements other than those obtained from waste or combustion residues, e.g. burned clay; Treating inorganic materials to improve their pozzuolanic characteristics (cements containing slag C04B7/14)} · CPC title

• C04B7/345

  Hydraulic cements not provided for in one of the groups C04B7/02 - C04B7/34 · CPC title

• C04B14/041

  Aluminium silicates other than clay · CPC title