Provided herein are methods of removing carbon dioxide from an aqueous stream or gaseous stream by: contacting the gaseous stream comprising carbon dioxide, when present, with an aqueous solution comprising ions capable of forming an insoluble carbonate salt; contacting the aqueous solution comprising carbon dioxide with an electroactive mesh that induces its alkalinization thereby forcing the precipitation of a carbonate solid from the solution and thereby the removal of dissolved inorganic carbon by electrolysis; and removing the precipitated carbonate solids from the solution, or the surface of the mesh where they may deposit. Also provided herein are flow-through electrolytic reactors comprising an intake device in fluid connection with a rotating cylinder comprising an electroactive mesh, and a scraping device and/or liquid-spray based device for separating a solid from the mesh surface.

Methods of controlling an amount of soluble base content of material comprising lithium carbonate and other material. Exemplary methods include using atomic layer deposition, selectively depositing one or more of an oxide, a fluoride, and a nitride to form and/or control the soluble base content.

The present invention provides a new method for fixing carbon dioxide. The method for fixing carbon dioxide of the present invention includes a contact step of bringing a mixed liquid containing sodium hydroxide and further containing at least one of a chloride of a Group 2 element or a chloride of a divalent metal element into contact with a gas containing carbon dioxide.

Provided herein are methods of removing carbon dioxide from an aqueous stream or gaseous stream by: contacting the gaseous stream comprising carbon dioxide, when present, with an aqueous solution comprising ions capable of forming an insoluble carbonate salt; contacting the aqueous solution comprising carbon dioxide with an electroactive mesh that induces its alkalinization thereby forcing the precipitation of a carbonate solid from the solution and thereby the removal of dissolved inorganic carbon by electrolysis; and removing the precipitated carbonate solids from the solution, or the surface of the mesh where they may deposit. Also provided herein are flow-through electrolytic reactors comprising an intake device in fluid connection with a rotating cylinder comprising an electroactive mesh, and a scraping device and/or liquid-spray based device for separating a solid from the mesh surface.

Provided herein are methods of removing carbon dioxide from an aqueous stream or gaseous stream by: contacting the gaseous stream comprising carbon dioxide, when present, with an aqueous solution comprising ions capable of forming an insoluble carbonate salt; contacting the aqueous solution comprising carbon dioxide with an electroactive mesh that induces its alkalinization thereby forcing the precipitation of a carbonate solid from the solution and thereby the removal of dissolved inorganic carbon by electrolysis; and removing the precipitated carbonate solids from the solution, or the surface of the mesh where they may deposit. Also provided herein are flow-through electrolytic reactors comprising an intake device in fluid connection with a rotating cylinder comprising an electroactive mesh, and a scraping device and/or liquid-spray based device for separating a solid from the mesh surface.

Shippable modular units configured for use in sequestering CO.sub.2 are provided. Aspects of the units include a support having one or more of: a CO.sub.2 gas/liquid contactor subunit, a carbonate production subunit and an alkali enrichment subunit; associated therewith. Also provided are systems made up of one or more such modular units, and methods for using the units/systems in CO.sub.2 sequestration protocols.

Shippable modular units configured for use in sequestering CO.sub.2 are provided. Aspects of the units include a support having one or more of: a CO.sub.2 gas/liquid contactor subunit, a carbonate production subunit and an alkali enrichment subunit; associated therewith. Also provided are systems made up of one or more such modular units, and methods for using the units/systems in CO.sub.2 sequestration protocols.

Methods and systems for producing hydrogen substantially without greenhouse gas emissions, the method including producing a product gas comprising hydrogen and carbon dioxide from a hydrocarbon fuel source; separating hydrogen from the product gas to create a hydrogen product stream and a byproduct stream; injecting the byproduct stream into a reservoir containing mafic rock; and allowing components of the byproduct stream to react in situ with components of the mafic rock to precipitate and store components of the byproduct stream in the reservoir.

Methods of sequestering carbon dioxide (CO.sub.2) are provided. Aspects of the methods include contacting a CO.sub.2 containing gaseous stream with an aqueous medium under conditions sufficient to produce a bicarbonate rich product. The resultant bicarbonate rich product (or a component thereof) is then combined with a cation source under conditions sufficient to produce a solid carbonate composition and product CO.sub.2 gas, followed by injection of the product CO.sub.2 gas into a subsurface geological location to sequester CO.sub.2. Also provided are systems configured for carrying out the methods.

Methods of sequestering carbon dioxide (CO.sub.2) are provided. Aspects of the methods include contacting a CO.sub.2 containing gaseous stream with an aqueous medium under conditions sufficient to produce a bicarbonate rich product. The resultant bicarbonate rich product (or a component thereof) is then combined with a cation source under conditions sufficient to produce a solid carbonate composition and product CO.sub.2 gas, followed by injection of the product CO.sub.2 gas into a subsurface geological location to sequester CO.sub.2. Also provided are systems configured for carrying out the methods.