Reaction schemes involving acids and bases; reactors comprising spatially varying chemical composition gradients; and associated systems and methods

Patent metadata

Field	Value
Publication number	US-12330989-B2
Application number	US-202318395402-A
Country	US
Kind code	B2
Filing date	Dec 22, 2023
Priority date	Jan 16, 2019
Publication date	Jun 17, 2025
Grant date	Jun 17, 2025

Abstract

Reaction schemes involving acids and bases; reactors comprising spatially varying chemical composition gradients (e.g., spatially varying pH gradients), and associated systems and methods, are generally described. For example, methods comprising producing an acid; dissolving a material comprising calcium in the acid to produce calcium ions; treating the calcium ions to produce solid calcium hydroxide and/or calcium oxide; and utilizing the solid calcium hydroxide and/or calcium oxide in a downstream process to produce a cement, wherein the downstream process comprises heating the solid calcium hydroxide and/or calcium oxide in a kiln are described.

First claim

What is claimed is:

1. A method comprising:
producing an acid;
dissolving a material comprising calcium in the acid to produce calcium ions;
treating the calcium ions to produce solid calcium hydroxide and/or calcium oxide; and
utilizing the solid calcium hydroxide and/or calcium oxide in a downstream process to produce a cement, wherein the downstream process comprises heating the solid calcium hydroxide and/or calcium oxide in a kiln; and
wherein the material further comprises magnesium and/or nickel.

2. The method of claim 1 , wherein producing the solid calcium hydroxide and/or calcium oxide comprises producing a byproduct different from the calcium hydroxide and/or calcium oxide.

3. The method of claim 2 , further comprising collecting the byproduct.

4. The method of claim 1 , wherein the downstream process comprises heating the solid calcium hydroxide and/or calcium oxide with silica and/or alumina in the kiln.

5. The method of claim 1 , wherein the downstream process comprises heating the solid calcium hydroxide and/or calcium oxide with silicate in the kiln.

6. The method of claim 1 , wherein the cement is Portland cement.

7. The method of claim 1 , wherein dissolving the material in the acid occurs in a region of a reactor with a pH of 6 or less.

8. The method of claim 1 , wherein the material comprises calcium carbonate, magnesium carbonate, and/or nickel carbonate.

9. The method of claim 1 , wherein the downstream process comprises heating the calcium hydroxide in a heater to convert the calcium hydroxide to calcium oxide, and heating the calcium oxide in the kiln.

10. The method of claim 1 , further comprising mixing the cement with water and an additive to form a concrete.

11. The method of claim 1 , wherein dissolving the material in the acid occurs in a region of a reactor with a pH of 4 or less.

12. A method comprising:
producing an acid;
dissolving a material comprising calcium in the acid to produce calcium ions;
treating the calcium ions to produce solid calcium hydroxide and/or calcium oxide; and
utilizing the solid calcium hydroxide and/or calcium oxide in a downstream process to produce a cement, wherein the downstream process comprises heating the solid calcium hydroxide and/or calcium oxide with silica, alumina, and/or silicate in a kiln; and
wherein the material further comprises magnesium and/or nickel.

13. The method of claim 12 , wherein producing the solid calcium hydroxide and/or calcium oxide comprises producing a byproduct different from the calcium hydroxide and/or calcium oxide.

14. The method of claim 13 , further comprising collecting the byproduct.

15. The method of claim 14 , wherein the cement is Portland cement.

16. The method of claim 15 , wherein dissolving the material in the acid is in a region of a reactor with a pH of 6 or less.

17. The method of claim 16 , further comprising mixing the cement with water and an additive to form a concrete.

18. The method of claim 15 , wherein dissolving the material in the acid occurs in a region of a reactor with a pH of 4 or less.

19. The method of claim 12 , wherein the material comprises calcium carbonate, magnesium carbonate, and/or nickel carbonate.

20. The method of claim 12 , wherein the downstream process comprises heating the calcium hydroxide in a heater to convert the calcium hydroxide to calcium oxide, and heating the calcium oxide with silica, alumina, and/or silicate in the kiln.

Assignees

• Massachusetts Inst Technology

Inventors

• Chiang Yet-Ming
• Ellis Leah
• Badel Andres

Classifications

• Y02P40/121

  Energy efficiency measures, e.g. improving or optimising the production methods · CPC title

• C04B7/06 Primary

  using alkaline raw materials (C04B7/60 takes precedence) · CPC title

• Y02P40/18

  Carbon capture and storage [CCS] · CPC title

• C04B2290/20

  Integrated combined plants or devices, e.g. combined foundry and concrete plant · CPC title

• B01J2219/00033

  Continuous processes · CPC title