Methods for low energy inorganic material synthesis

Patent metadata

Field	Value
Publication number	US-11332847-B2
Application number	US-201616067180-A
Country	US
Kind code	B2
Filing date	Dec 29, 2016
Priority date	Dec 29, 2015
Publication date	May 17, 2022
Grant date	May 17, 2022

Abstract

The present invention relates to solvothermal vapor synthesis methods for the crystallization of a phase from a mixture of selected inorganic or organic precursors in an unsaturated vapor-phase reaction medium.

First claim

The invention claimed is:

1. A method of increasing the reaction yield of β-CaSiO 3 produced by hydrothermal vapor synthesis from calcite and quartz, the method comprising:
blending a source of CaCO 3 (calcite) and a source of SiO 2 (quartz), wherein the source of CaCO 3 is limestone, the source of SiO 2 is siliceous sand, the initial particle size of said sand comprises 100 mesh particles and the initial particle size of said limestone comprises 150 mesh particles, provided that the sand particles do not comprise 350 mesh particles and the limestone particles do not comprise 600 mesh particles;
mixing the limestone and sand blend with a 5 to 25 wt % NaCl solution and drying said mixture, followed by drying and further mixing until a uniform and homogeneous reaction mixture is obtained;
adding said mixture and water to a reaction vessel, wherein the amount of water added to the reaction vessel is sufficient to obtain a partial pressure of water between 700 and 900 psi when the reaction vessel is sealed and heated to a reaction temperature between 350 and 450° C.; and
heating the reaction vessel between 350 and 450° C.;
wherein the amount of NaCl and the degree of uniformity and homogeneity of said reaction mixture is effective to provide a yield of the β-CaSiO 3 reaction product between 20 and 60 wt % in under one hour.

2. The method of claim 1 , wherein the reaction vessel is heated for 1 hour or less.

3. The method of claim 1 , wherein the amount of water added to the reaction vessel is sufficient to obtain a partial pressure of water of 700 psi.

4. The method of claim 1 , wherein the reaction vessel is heated to a reaction temperature of 350° C.

5. The method of claim 1 , wherein the reaction vessel is heated for a period of 1 hour.

6. The method of claim 1 , wherein the mole ratio between the source of SiO 2 and the source of CaCO 3 ranges from about 0.5:1 to about 3:1.

7. The method of claim 1 wherein the mole ratio between the source of SiO 2 and the CaCO 3 source is between 1:2 and 2:1.

8. The method of claim 1 , wherein the source of CaCO 3 comprises more than about 70% calcium carbonate by weight.

9. The method of claim 1 , wherein the mixture is suspended above the water within the reaction vessel.

10. The method of claim 1 , wherein the reaction vessel is a continuous reaction vessel.

11. The method of claim 1 , wherein the reaction vessel is a batch reaction vessel.

12. The method of claim 1 , wherein the reaction vessel is a semi-continuous reaction vessel.

13. The method of claim 1 , further comprising changing the amount of water to adjust the partial pressure during the step of heating the reaction vessel.

14. The method of claim 1 , wherein the amount of water ranges from about 5% to about 25% of the total volume of the reaction vessel.

15. The method of claim 1 , wherein the amount of water ranges from about 10% to about 16% of the total volume of the reaction vessel.

16. The method of claim 1 , wherein the reaction vessel is heated to a temperature between 350 and 400° C.

17. The method of claim 1 wherein the mole ratio between the source of SiO 2 and the CaCO 3 source is between 0.6:1 and 1:1.

Assignees

• Univ Rutgers

Inventors

• Riman Richard E
• Kopp Daniel

Classifications

• C04B35/468

  based on barium titanates · CPC title

• C30B1/12

  by pressure treatment during the growth · CPC title

• C04B35/64

  Burning or sintering processes (C04B33/32 takes precedence {; powder metallurgy B22F}) · CPC title

• C04B2235/604

  Pressing at temperatures other than sintering temperatures · CPC title

• C04B35/44

  based on aluminates · CPC title