Abstract: Aspects of the invention include a method of producing a cement material comprising step of: first reacting a calcium-bearing starting material with a first acid to produce an aqueous first calcium salt; second reacting the aqueous first calcium salt with a second acid to produce a solid second calcium salt; wherein the second acid is different from the first acid and the second calcium salt is different from the first calcium salt; and thermally treating the second calcium salt to produce a first cement material. Preferably, but not necessarily, during the second reacting step, reaction between the first calcium salt and the second acid regenerates the first acid.

Abstract: A method for producing a cement material wherein 1) a first acid is reacted with a first cement precursor to form a second cement precursor, and 2) the second cement precursor is converted to a cement material. The first cement precursor includes one or more of Ca, Si, or Al, and the reaction with the first acid produces a second cement precursor that includes one or more of Ca, Si, or Al, and the conjugate base of the first acid. The second step can be performed by thermally converting the second cement precursor to a cement material by sintering or thermally decomposing the second cement precursor at a temperature in the range of 500 to 2000° C. The first step can be performed in the presence of water as a wet slurry. The concentration of the first acid can be greater than 20% by weight.

Abstract: Aspects of the invention include a method of producing a cement material comprising step of: first reacting a calcium-bearing starting material with a first acid to produce an aqueous first calcium salt; second reacting the aqueous first calcium salt with a second acid to produce a solid second calcium salt; wherein the second acid is different from the first acid and the second calcium salt is different from the first calcium salt; and thermally treating the second calcium salt to produce a first cement material. Preferably, but not necessarily, during the second reacting step, reaction between the first calcium salt and the second acid regenerates the first acid.

Abstract: A method for producing a cement material wherein 1) a first acid is reacted with a first cement precursor to form a second cement precursor, and 2) the second cement precursor is converted to a cement material. The first cement precursor includes one or more of Ca, Si, or Al, and the reaction with the first acid produces a second cement precursor that includes one or more of Ca, Si, or Al, and the conjugate base of the first acid. The second step can be performed by thermally converting the second cement precursor to a cement material by sintering or thermally decomposing the second cement precursor at a temperature in the range of 500 to 2000° C. The first step can be performed in the presence of water as a wet slurry. The concentration of the first acid can be greater than 20% by weight.

Abstract: Aspects of the invention include a method of producing a cement material comprising step of: first reacting a calcium-bearing starting material with a first acid to produce an aqueous first calcium salt; second reacting the aqueous first calcium salt with a second acid to produce a solid second calcium salt; wherein the second acid is different from the first acid and the second calcium salt is different from the first calcium salt; and thermally treating the second calcium salt to produce a first cement material. Preferably, but not necessarily, during the second reacting step, reaction between the first calcium salt and the second acid regenerates the first acid.

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.

Abstract: Aspects of the invention include a method of producing a cement material comprising step of: first reacting a calcium-bearing starting material with a first acid to produce an aqueous first calcium salt; second reacting the aqueous first calcium salt with a second acid to produce a solid second calcium salt; wherein the second acid is different from the first acid and the second calcium salt is different from the first calcium salt; and thermally treating the second calcium salt to produce a first cement material. Preferably, but not necessarily, during the second reacting step, reaction between the first calcium salt and the second acid regenerates the first acid.

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.

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.

Abstract: Aspects of the invention include a method of producing a cement material comprising step of: first reacting a calcium-bearing starting material with a first acid to produce an aqueous first calcium salt; second reacting the aqueous first calcium salt with a second acid to produce a solid second calcium salt; wherein the second acid is different from the first acid and the second calcium salt is different from the first calcium salt; and thermally treating the second calcium salt to produce a first cement material. Preferably, but not necessarily, during the second reacting step, reaction between the first calcium salt and the second acid regenerates the first acid.

Abstract: A self-diagnostic maintenance system for wastewater treatment employs unique environmental sensor configurations to link operational states of a water treatment system with unique failure modes of the system. Upon detection of failure modes, the maintenance system alerts users and operators via a short messaging service (SMS) of the problem, and can display step-by-step pictorial repair instructions for the operator to replace broken or malfunctioning parts, without the operator needing to diagnosis the problem or understand the detailed workings of the wastewater treatment system.

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.

Abstract: The disclosure provides for thin films that can be used to tune the catalytic characteristics of heterogeneous electrocatalysts.

Abstract: A self-diagnostic maintenance system for wastewater treatment employs unique environmental sensor configurations to link operational states of a water treatment system with unique failure modes of the system. Upon detection of failure modes, the maintenance system alerts users and operators via a short messaging service (SMS) of the problem, and can display step-by-step pictorial repair instructions for the operator to replace broken or malfunctioning parts, without the operator needing to diagnosis the problem or understand the detailed workings of the wastewater treatment system.