Disclosed is a magnesium-based cementitious material, preparation method and application thereof. The magnesium-based cementitious material, comprising magnesite, sandstone, and water, wherein: the magnesite is provided with CaO, SiO.sub.2, Al.sub.2O.sub.3, Fe.sub.2 O.sub.3, and MgO, a mass percentage of the CaO is less than 5%, a mass percentage of SiO.sub.2 is less than 5%, a mass percentage of Al.sub.2 O.sub.3 is less than 5%, a mass percentage of Fe.sub.2 O.sub.3 is less than 7%, a mass percentage of MgO is between 37% and 50%; the sandstone is provided with SiO.sub.2, CaO, Al.sub.2 O.sub.3, and Fe.sub.2O.sub.3, a mass percentage of SiO.sub.2 is greater than 70%. The beneficial effects of this disclosure are: the cementitious material does not contain MgCl.sub.2, which avoids the reduction of the strength of the cementitious material due to the dissolution of MgCl.sub.2 in water; the magnesium-based cementitious material of this disclosure is immiscible with water and has strong water resistance.

Disclosed is a magnesium-based cementitious material, preparation method and application thereof. The magnesium-based cementitious material, comprising magnesite, sandstone, and water, wherein: the magnesite is provided with CaO, SiO.sub.2, Al.sub.2O.sub.3, Fe.sub.2 O.sub.3, and MgO, a mass percentage of the CaO is less than 5%, a mass percentage of SiO.sub.2 is less than 5%, a mass percentage of Al.sub.2 O.sub.3 is less than 5%, a mass percentage of Fe.sub.2 O.sub.3 is less than 7%, a mass percentage of MgO is between 37% and 50%; the sandstone is provided with SiO.sub.2, CaO, Al.sub.2 O.sub.3, and Fe.sub.2O.sub.3, a mass percentage of SiO.sub.2 is greater than 70%. The beneficial effects of this disclosure are: the cementitious material does not contain MgCl.sub.2, which avoids the reduction of the strength of the cementitious material due to the dissolution of MgCl.sub.2 in water; the magnesium-based cementitious material of this disclosure is immiscible with water and has strong water resistance.

Provided herein are compositions, methods, and systems comprising vaterite and magnesium oxide.

Provided herein are compositions, methods, and systems comprising vaterite and magnesium oxide.

A manufacturing process of a concrete product includes: (1) extracting calcium from solids as portlandite; (2) forming a cementitious slurry including the portlandite; (3) shaping the cementitious slurry into a structural component; and (4) exposing the structural component to carbon dioxide sourced from a flue gas stream, thereby forming the concrete product.

A manufacturing process of a concrete product includes: (1) extracting calcium from solids as portlandite; (2) forming a cementitious slurry including the portlandite; (3) shaping the cementitious slurry into a structural component; and (4) exposing the structural component to carbon dioxide sourced from a flue gas stream, thereby forming the concrete product.

A manufacturing process of a concrete product includes: (1) extracting calcium from solids as portlandite; (2) forming a cementitious slurry including the portlandite; (3) shaping the cementitious slurry into a structural component; and (4) exposing the structural component to carbon dioxide sourced from a flue gas stream, thereby forming the concrete product.

A manufacturing process of a concrete product includes: (1) extracting calcium from solids as portlandite; (2) forming a cementitious slurry including the portlandite; (3) shaping the cementitious slurry into a structural component; and (4) exposing the structural component to carbon dioxide sourced from a flue gas stream, thereby forming the concrete product.

An ultrastable cementitious material with nano-molecular veneer makes a cementitious material by blending 29 wt % to 40 wt % of a magnesium oxide dry powder containing 80 wt % to 98 wt % of magnesium oxide based on a final total weight of the cementitious material, with 14 wt % to 18 wt % of a magnesium chloride dissolved in water and reacting to form a liquid suspension, mixing from 2 to 10 minutes, adding a phosphorus-containing material, and allowing the liquid suspension to react into an amorphous phase cementitious material, wherein a portion of the amorphous phase cementitious material grows a plurality of crystals. The plurality of crystals are encapsulated by the amorphous phase cementitious material forming a nano-molecular veneer. A process to make the ultrastable cementitious material. A tile backer board incorporating the ultrastable cementitious material and a process for making the tile backer board.

A manufacturing process of a concrete product includes: (1) extracting calcium from solids as portlandite; (2) forming a cementitious slurry including the portlandite; (3) shaping the cementitious slurry into a structural component; and (4) exposing the structural component to carbon dioxide sourced from a flue gas stream, thereby forming the concrete product.