Process to convert reduced sulfur species and water into hydrogen and sulfuric acid

Patent metadata

Field	Value
Publication number	US-2022411940-A1
Application number	US-202217894674-A
Country	US
Kind code	A1
Filing date	Aug 24, 2022
Priority date	May 18, 2018
Publication date	Dec 29, 2022
Grant date	—

Abstract

In an aspect, provided herein are methods for producing sulfuric acid and hydrogen gas, the methods comprising steps of: providing sulfur dioxide formed by thermal conversion of a sulfur-containing species; electrochemically oxidizing said sulfur dioxide to sulfuric acid in the presence of water; and electrochemically forming hydrogen gas via a reduction reaction. In some embodiments, the methods comprise a step of thermally converting said sulfur-containing species to said sulfur dioxide. Systems configured to perform these methods are also disclosed herein. Also provided herein are methods and systems for producing sulfuric acid and hydrogen gas by electrochemically forming the sulfuric acid and the hydrogen gas in a mixture comprising a sulfur material, a supporting acid, and water. Also provided herein are methods and systems for producing a cement material.

First claim

We claim:

1 . A method for producing a cement material comprising:
(a) reacting a first acid and a first cement precursor to form a second cement precursor; and (b) converting the second cement precursor to a cement material.

2 . The method of claim 1 , wherein the first cement precursor comprises an element selected from the group consisting of Ca, Si, or Al, or a combination of thereof.

3 . The method of claim 1 , wherein step (a) is performed in the presence of water as a wet slurry.

4 . The method of claim 1 , wherein the second cement precursor comprises an element selected from the group consisting of Ca, Si, or Al, or a combination thereof.

5 . The method of claim 1 , wherein the second cement precursor comprises Ca.

6 . The method of claim 1 , wherein the first acid is at a concentration of greater than or equal to 20% by mass.

7 . The method of claim 1 , wherein converting the second cement precursor to a cement material comprises thermally converting the second cement precursor at an appropriate temperature for sintering or thermally decomposing the second cement precursor thereby forming the cement material.

8 . The method of claim 7 , wherein thermally converting comprises treating at a temperature selected from the range of 500 to 2000° C.

9 . The method of claim 7 , wherein thermally converting occurs in the presence of an additive.

10 . The method of claim 9 , wherein the additive comprises silica, alumina, or iron oxide, or a combination thereof.

11 . The method of claim 10 , wherein the additive comprises silica.

12 . The method of claim 11 , wherein the cement material comprises one or more silicates.

13 . The method of claim 10 , wherein the additive comprises alumina and/or iron oxide.

14 . The method of claim 1 , wherein the cement material comprises CaO.

15 . The method of claim 1 , wherein the cement material comprises a composite cement material.

16 . The method of claim 1 , further comprising adding one or more aggregates to the cement material to produce a composite cement material.

17 . The method of claim 16 , wherein the aggregate comprises sand and gravel and the composite cement material comprises concrete.

18 . The method of claim 16 , wherein the aggregate comprises fine aggregates and the composite cement material comprises mortar.

19 . The method of claim 1 , further comprising capturing and storing carbon dioxide (CO 2 ).

20 . The method of claim 19 , wherein the captured CO 2 comprises a bicarbonate.

21 . A system for producing a cement material comprising:
(a) an apparatus configured to react a first acid and a first cement precursor to form a second cement precursor; and (b) an apparatus configured to convert the second cement precursor to a cement material, wherein (a) and (b) are operably connected.

22 . The system of claim 21 , wherein the apparatus of (b) comprises a heated vessel, wherein the apparatus is configured to thermally convert the second cement precursor to the cement material inside the heated vessel.

23 . The system of claim 22 , wherein the heated vessel is configured to thermally convert the second cement precursor at a temperature selected from the range of 500 to 2000° C.

24 . The system of claim 22 , wherein the heated vessel comprises a cement kiln.

25 . The system of claim 21 , further configured to add one or more additives to the second cement precursor prior to conversion.

26 . The system of claim 25 , wherein the additive comprises silica, alumina, iron oxide, or any combination of these.

27 . The system of claim 26 , wherein the additive comprises silica.

28 . The system of claim 26 , wherein the additive comprises alumina and/or iron oxide.

29 . The system of claim 21 , further comprising an apparatus configured to capture and store carbon dioxide (CO 2 ).

30 . A system for producing a composite cement material comprising:
(a) an apparatus configured to receive a cement material produced by the method of claim 1 ; and (b) an apparatus configured to combine the cement material with water and aggregates, to form concrete.

Assignees

• California Inst Of Techn

Inventors

• Finke Cody E

Classifications

• B09C2101/00

  In situ · CPC title

• C05G5/23

  Solutions · CPC title

• C05B11/08

  using sulfuric acid · CPC title

• C02F1/66

  by neutralisation; pH adjustment (for degassing C02F1/20; using ion-exchange C02F1/42; for flocculation or precipitation of suspended impurities C02F1/52; for removing dissolved compounds C02F1/58) · CPC title

• C25B1/02

  Hydrogen or oxygen · CPC title