The present invention discloses the systems of producing calcium and magnesium carbonate from the Ca/Mg containing solution leached by a CO.sub.2-based hydrometallurgical process which includes: a precipitation reactor that the Ca/Mg containing leached solution is continuously added and fully mixed with the alkaline reagent at specific mole ratio into the precipitation reactor and the reactor also comprises a CO.sub.2 bubbling module where CO.sub.2 is captured and recirculated from the thermal decomposition process as needed; a solid-liquid separation unit that the treated slurry is treated by the solid-liquid separation unit to produce precipitated calcium and magnesium carbonate products where the recirculating water is recycled back into the precipitation reactor; a thermal decomposition unit that the calcium and magnesium carbonate products is calcined by the thermal decomposition unit to produce an alkaline reagent and the alkaline reagent is recycled back into the precipitation reactor for the next batch of reaction.

The invention discloses a method of producing a filler composition to be used in paper or board production, said method comprising providing a suspension comprising calcium hydroxide and performing carbonation of the calcium hydroxide to form precipitated calcium carbonate (PCC). The invention is characterized in that starch and/or carboxy methyl cellulose (CMC) is added to the suspension during said carbonation of calcium hydroxide. The method of the invention enables an increased filler content in paper or paperboard without substantially increasing the dusting tendency or decreasing the strength of the paper or board.

CO.sub.2, and other gases are utilized with mineral feedstock to synthesize products. The synthesized products, as the result of liquid, solid, gas photo-chemical reactions within the advanced bioreactor of the disclosed embodiment, are precipitated raw material for multiple consumer and industrial products. Waste heat, pressure and torque produced from the bioreactor are utilized for generating electricity and/or heat through a combination of energy recovery devices. Energy recovery devices offsets and lower the cost of operating the reactor as the disclosed reactor integrates photolysis via ultra-violet light, as an integral component, of a reactor system, composed also of an active mixer-agitator assembly, pressure and vacuum vessel chamber, heat source, and ports for media ingestion. The disclosed reactor is designed be conducive to transforming gaseous, solid, and liquid feedstock, like carbon dioxide —CO.sub.2, and other feedstocks that are inorganic and/or organic in an aqueous medium, into inorganic and organic products.

The present disclosure provides systems for carbon capture in combination with production of one or more industrially useful materials. The disclosure also provides methods for carrying out carbon capture in combination with an industrial process. In particular, carbon capture can include carrying out calcination in a reactor, separation of carbon dioxide rich flue gases from industrially useful products, and capture of at least a portion of the carbon dioxide for sequestration of other use, such as enhanced oil recovery.

The present invention relates to a process to produce high purity strontium sulfate and strontium carbonate from subterranean brines. The present disclosure also relates to chemical precipitations of subterranean brines to isolate strontium from divalent cations, such as calcium and barium. Such precipitations include the use of sulfate and subsequent solids separations and washing of the precipitate. In a latter step in the strontium carbonate process, a metathesis reaction with a carbonate is performed upon the strontium sulfate to produce strontium carbonate while allowing optional recycling of the sulfate. An additional rinse with acid or water of the strontium sulfate may be performed prior to metathesis to increase the purity of the resulting strontium carbonate.

Disclosed herein are compositions comprising oolitic aragonite particles, wherein the oolitic aragonite particles have an average particle size of between 100 nm to 1 mm, and a Hunter brightness level greater than 88. Further disclosed herein are personal care and/or cosmetic compositions, comprising a carrier and the aforementioned oolitic aragonite particles. Further disclosed herein are methods of making and using the oolitic aragonite particles.

Provided are a method for producing calcium carbonate having a controlled size and a method for growing crystals in order to produce calcium carbonate having a controlled size. A method for producing a calcium carbonate comprises the steps of reducing the pH of an aqueous calcium carbonate dispersion to 9.0 or less and then increasing the pH of the aqueous calcium carbonate dispersion to grow calcium carbonate particles.

Provided are a method for producing calcium carbonate having a controlled size and a method for growing crystals in order to produce calcium carbonate having a controlled size. A method for producing a calcium carbonate comprises the steps of reducing the pH of an aqueous calcium carbonate dispersion to 9.0 or less and then increasing the pH of the aqueous calcium carbonate dispersion to grow calcium carbonate particles.

Compositions and methods for oxidizing organic contaminants while sequestering inhibitory forms of carbon. An oxidant capable of producing free radicals oxidizes organic contaminants. A metal oxide, metal hydroxide, or metal peroxide generates a soluble hydroxide concentration of about 1×10.sup.−4 M or greater to convert carbonic acid, bicarbonate ion, methane, elemental carbon, and other organic forms of carbon to carbonate ion. A metal having a carbonate with a lower solubility product constant than its hydroxide precipitates the carbonate ion as a metal carbonate, thereby eliminating soluble carbonate as a radical scavenger. Compositions and methods that additionally minimize metal solubilization and sequester solubilized metals are also disclosed.

A lost circulation material (LCM) is provided having an alkaline nanosilica dispersion and an ester activator. The alkaline nanosilica dispersion and the ester activator may form a gelled solid after interaction over a contact period. Methods of lost circulation control using the LCM are also provided.