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.

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.

The invention relates to a process for the production of silicon and alumina Aluminium is contacted with a molten slag of a calcium oxide and SiO.sub.2 under conditions facilitating an aluminothermic reaction, thereby forming silicon and an aluminate slag in two phases which are separated. The aluminate slag is converted to alumina and calcium oxide, which is re-fed in the reaction. The aluminium is provided by melting of aluminium scrap or a combination of different aluminium alloys at a temperature of 700 to 1000° C. The primary aluminium melt is adjusted to a content of 8 to 14% of silicon and then cooled to below 660° C., whereby precipitates are formed, and high purity aluminium is obtained to be introduced into the reaction.

A system and method for producing commercial strength solutions of aluminum chlorohydrate are provided. The method includes providing aluminum chlorohydrate monohydrate (ACHMH) powder, heating water to at least 120 F. and less than 200 F., and dissolving at least a portion of the ACHMH powder into the heated water to form the solution of aluminum chlorohydrate. The produced solution of aluminum chlorohydrate from the ACHMH powder has an aluminum oxide concentration ranging from about 18 wt % to about 27 wt %, has a basicity ranging from greater than 74% and less than 83%, and has a freezing point ranging from about 10 F. to about 16 F. The solution may also have an iron content of between about 0 to about 70 ppm as Fe.

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.

The invention relates to a method for producing coagulant aluminium salts. Raw material comprising at least one aluminium oxide compound is mixed with a process acid or a base to form a reaction mixture, which is heated to a reaction temperature of at least 100 C. at a reaction pressure. The aluminium oxide compound is allowed to react with the process acid or the base. The aluminium oxide compound is selected from a group consisting of amorphous aluminium oxide, -aluminium oxide, -aluminium oxide, -aluminium oxide, or any of their mixtures. The reaction pressure is at least 2 bar(g).

The invention relates to a method for producing coagulant aluminium salts. Raw material comprising at least one aluminium oxide compound is mixed with a process acid or a base to form a reaction mixture, which is heated to a reaction temperature of at least 100 C. at a reaction pressure. The aluminium oxide compound is allowed to react with the process acid or the base. The aluminium oxide compound is selected from a group consisting of amorphous aluminium oxide, -aluminium oxide, -aluminium oxide, -aluminium oxide, or any of their mixtures. The reaction pressure is at least 2 bar(g).

A process for extracting values from lithium slag comprising: (a) hydrothermally treating lithium slag with an aqueous solution of an alkaline compound at selected temperature and duration; (b) performing an ion exchange step on the alkaline treated lithium slag; and (c) recovering values selected from the group consisting of aluminium compounds, silicon compounds and compounds containing silicon and aluminium.

A method of producing aluminum chlorohydrate comprises adding small form aluminum metal pellets to a reactant receiving space of a reactor tank to form a pellet bed; adding aqueous hydrochloric acid to the reactant receiving space of the reactor tank; and continuously circulating the aqueous hydrochloric acid through the pellet bed. In some embodiments, the continuously circulating aqueous hydrochloric acid dispels reaction gases from the pellet bed. Methods described herein can, in some cases, further comprise consecutively adding additional small form aluminum metal pellets to the reactant receiving space of the reactor tank as the small form aluminum metal pellets are consumed in the pellet bed.

A method of producing aluminum chlorohydrate comprises adding small form aluminum metal pellets to a reactant receiving space of a reactor tank to form a pellet bed; adding aqueous hydrochloric acid to the reactant receiving space of the reactor tank; and continuously circulating the aqueous hydrochloric acid through the pellet bed. In some embodiments, the continuously circulating aqueous hydrochloric acid dispels reaction gases from the pellet bed. Methods described herein can, in some cases, further comprise consecutively adding additional small form aluminum metal pellets to the reactant receiving space of the reactor tank as the small form aluminum metal pellets are consumed in the pellet bed.