Granted Patent B2

US 12,612,701 · App. 17/505,073 · Granted Apr 28, 2026

Inventor: Cody E. Finke (Pasadena, CA)

Assignee: California Institute of Technology

C25B1/22B09C1/08C02F1/66C04B2/10C05B11/08C09K17/02C25B1/02C25B9/17H01M8/0656

Abstract

Claims (64)

1 . A method for producing a cement material, said method comprising steps of:

a. reacting sulfur dioxide and water to form a first acid, the first acid comprising at least one sulfur-containing anion;

b. reacting the first acid and a first cement precursor to form a second cement precursor different from the first cement precursor; wherein the second cement precursor comprises the at least one sulfur-containing anion; and

c. converting the second cement precursor to the cement material, the cement material being different from both the first and second cement precursors;

wherein step (c) comprises forming the cement material and sulfur dioxide.

2 . The method of claim 1 , wherein the sulfur-containing anion is a sulfate (SO 4 ) or a sulfite (SO 3 ).

3 . The method of claim 1 , wherein the cement material is calcium oxide (CaO) and the first cement precursor comprises calcium carbonate (CaCO 3 ).

4 . The method of claim 1 , wherein:

the sulfur-containing anion is sulfate (SO 4 );

the first acid is sulfuric acid (H 2 SO 4 );

the step (a) comprises (i) electrochemically oxidizing the sulfur dioxide to the sulfuric acid and (ii) electrochemically forming hydrogen gas via a reduction reaction; and

the sulfur dioxide and the water are reacted at a ratio of 1:2, respectively, during step (a).

5 . The method of claim 4 , wherein the step (a) is performed according to formula FX1:

SO 2 +2H 2 O→H 2 SO 4 +H 2   (FX1).

6 . The method of claim 4 , wherein the second cement precursor is calcium sulfate (CaSO 4 ) and wherein the step (c) is performed according to formula FX3:

CaSO 4 →CaO+SO 2 +½O 2   (FX3).

7 . The method of claim 4 , wherein the steps of electrochemically oxidizing the sulfur dioxide and electrochemically forming the hydrogen gas are performed in the presence of a catalyst.

8 . The method of claim 4 , comprising burning at least a fraction of the formed hydrogen gas to provide heat for step (c).

9 . The method of claim 4 , wherein the first cement precursor comprises calcium carbonate (CaCO 3 ); and wherein step (b) is performed according to formula FX2a:

H 2 SO 4 +CaCO 3 →CaSO 4 +CO 2 +H 2 O  (FX2a).

10 . The method of claim 9 , wherein the method is characterized by a net reaction having the formula FX4a:

CaCO 3 +H 2 O→H 2 +CaO+½O 2 +CO 2   (FX4a).

11 . The method of claim 4 , wherein the first cement precursor comprises calcium carbonate (CaCO 3 ); and wherein step (b) is performed according to formula FX2b:

H 2 SO 4 +2CaCO 3 →CaSO 4 +Ca 2+ +2HCO 3 −   (FX2b).

12 . The method of claim 4 , wherein the method is characterized by a net reaction having the formula FX4b:

2CaCO 3 +2H 2 O→H 2 +CaO+½O 2 +Ca 2+ +2HCO 3 −   (FX4b).

13 . The method of claim 1 , wherein:

the sulfur-containing anion is sulfite (SO 3 );

the first acid is sulfurous acid (H 2 SO 3 ); and

the sulfur dioxide and the water are reacted at a ratio of equal to or less than 1:1, respectively, during step (a).

14 . The method of claim 13 , wherein the step (a) is performed according to formula FX5:

SO 2 +H 2 O→H 2 SO 3   (FX5).

15 . The method of claim 13 , wherein the second cement precursor is calcium sulfite (CaSO 3 ).

16 . The method of claim 13 , wherein the step (c) is performed according to formula FX7:

CaSO 3 →CaO+SO 2   (FX7).

17 . The method of claim 13 , wherein the first cement precursor comprises calcium carbonate (CaCO 3 ); and wherein step (b) is performed according to formula FX6a:

H 2 SO 3 +CaCO 3 →CaSO 3 +CO 2 +H 2 O  (FX6a).

18 . The method of claim 13 , wherein the method is characterized by a net reaction having the formula FX8a:

CaCO 3 →CaO+CO 2   (FX8a).

19 . The method of claim 13 , wherein the first cement precursor comprises calcium carbonate (CaCO 3 ); and wherein step (b) is performed according to formula FX6b:

H 2 SO 3 +2CaCO 3 →CaSO 3 +Ca 2+ +2HCO 3 −   (FX6b).

20 . The method of claim 19 , wherein the method is characterized by a net reaction having the formula FX8b:

2CaCO 3 +H 2 O+heat→CaO+Ca 2+ +2HCO 3 −   (FX8b).

21 . The method of claim 11 , further comprising at least one of storing and recycling liquid comprising calcium ions and bicarbonate ions, wherein the calcium ions and bicarbonate ions are formed during step (b).

22 . The method of claim 1 , wherein sulfur dioxide is produced during step (c), the method further comprising recycling the sulfur dioxide produced during step (c) to provide for the sulfur dioxide reacted during step (a).

23 . The method of claim 1 , wherein step (c) comprises heating the second cement precursor in the presence of an additive to form a composite cement material, the composite cement material comprising the cement material.

24 . The method of claim 1 , wherein:

step (b) is performed without providing water during the reaction, except for the water produced by the reaction during step (b), such that step (b) is performed as a dry reaction; or

wherein step (b) comprises providing water during the reaction, in addition to the water produced by the reaction during step (b), such that step (b) is performed in a wet slurry.

25 . The method of claim 1 , wherein the converting the second cement precursor comprises thermally converting the second cement precursor thereby forming the cement material.

26 . The method of claim 1 , wherein the sulfur-containing anion is partially or fully decomposed in the step (c).

27 . The method of claim 1 , wherein, in the step (c), for each converted molecule of the second cement precursor, a sulfur-containing anion is decomposed.

28 . The method of claim 1 , wherein, in the step (c), for each converted molecule of the second cement precursor, a sulfur-containing anion is decomposed to form sulfur dioxide.

29 . The method of claim 1 , wherein the cement material is a Portland cement.

30 . A method for producing a cement material, said method comprising steps of:

a. reacting sulfur dioxide and water to form a first acid, the first acid comprising at least one sulfur-containing anion;

b. reacting the first acid and a first cement precursor to form a second cement precursor; wherein the second cement precursor comprises the at least one sulfur-containing anion; and

c. converting the second cement precursor to the cement material;

wherein:

step (c) comprises forming the cement material and sulfur dioxide;

the sulfur-containing anion is sulfate (SO 4 );

the first acid is sulfuric acid (H 2 SO 4 );

the step (a) comprises (i) electrochemically oxidizing the sulfur dioxide to the sulfuric acid and (ii) electrochemically forming hydrogen gas via a reduction reaction; and

the sulfur dioxide and the water are reacted at a ratio of 1:2, respectively, during step (a).

Assignments (1)

Continuity (7)

References Cited (217)