In a method for the precipitation of particles of a metal carbonate material comprising nickel and manganese in an atomic ratio of 0≤Ni:Mn≤1:3, aqueous solutions comprising sulfates or nitrates of nickel and manganese are mixed with aqueous solutions of carbonates or mixtures of carbonates and hydroxides of sodium or potassium in a stirred reactor at pH>7.5 without the use of a chelating agent. Thereby agglomerated particles are formed without any subsequent process steps, in particular no subsequent process at temperatures higher than the precipitation temperature.

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.

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.

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.

This invention describes a method and apparatus for the capture, storage and release of carbon dioxide for use in the horticulture industry, the method including reduction of a transition metal oxide to form a transition metal and carbon dioxide; carburization or partial carburization of the transition metal to form metal carbide; carbonation of an alkaline metal oxide or alkaline earth metal oxide to form an alkaline metal carbonate or alkaline earth metal carbonate; contacting the metal carbide with air to produce a transition metal oxide and carbon dioxide; and calcining the alkaline metal carbonate or alkaline earth metal carbonate to form carbon dioxide and alkaline metal oxide or alkaline earth metal oxide. Also described is a sorbent material for use in the method and apparatus of the invention.

This invention describes a method and apparatus for the capture, storage and release of carbon dioxide for use in the horticulture industry, the method including reduction of a transition metal oxide to form a transition metal and carbon dioxide; carburization or partial carburization of the transition metal to form metal carbide; carbonation of an alkaline metal oxide or alkaline earth metal oxide to form an alkaline metal carbonate or alkaline earth metal carbonate; contacting the metal carbide with air to produce a transition metal oxide and carbon dioxide; and calcining the alkaline metal carbonate or alkaline earth metal carbonate to form carbon dioxide and alkaline metal oxide or alkaline earth metal oxide. Also described is a sorbent material for use in the method and apparatus of the invention.

A method and apparatus of preparing lithium compound(s) from lithium-containing mineral includes a) a leaching step, wherein the lithium-containing mineral is leached in aqueous leach solution containing alkaline carbonate, for liberating lithium and phosphate(s) from the lithium-containing mineral, thus obtaining leach slurry containing lithium carbonate and phosphate(s) leach slurry, b) a carbonization step, wherein the leach slurry containing lithium carbonate and phosphate(s), obtained from the leaching step, is reacted with an alkali earth metal compound in the presence of CO.sub.2 for obtaining a carbonated slurry containing lithium hydrogen carbonate, and for precipitating phosphate(s) contained in the leach slurry as insoluble phosphate compound(s), c) a solid-liquid separation step, wherein the carbonated slurry obtained from carbonization step is subjected to solid-liquid separation wherein the undissolved mineral and phosphate compound(s) are separated as solids that can be recovered or discarded, thereby obtaining a solution containing lithium hydrogen carbonate.

The present invention relates to an apparatus and method of preparing carbonate and/or formate from carbon dioxide. The apparatus of preparing carbonate and/or formate from carbon dioxide (CO.sub.2), comprising: an electrolysis reactor comprising (i) an anode which contains an aqueous solution of a Group I metal salt as an electrolytic solution, (ii) an ion-exchange membrane through which metal cations derived from the Group I metal salt and water flow from an anode to a cathode, (iii) a cathode, and (iv) a gas diffusion layer which supplies a carbon dioxide-containing gas to the cathode; a power supply unit of applying a voltage between the anode and the cathode; a first gas-liquid separator of recovering the electrolytic solution from the products formed in the anode; a second gas-liquid separator of recovering carbonate and/or formate from the products formed in the cathode; a pH meter of measuring the pH of the electrolytic solution recovered from the first gas-liquid separator; a first reactant supply unit of supplying (a) the electrolytic solution recovered from the first gas-liquid separator and (b) the aqueous solution of the Group I metal salt with which the recovered electrolytic solution is replenished according to the pH of the electrolytic solution, to the anode; and a second reactant supply unit of supplying carbon dioxide or a mixer comprising carbon dioxide and water vapor to the cathode; wherein, when a voltage is applied between the anode and the cathode, in the anode, water undergoes electrolysis to generate hydrogen ions, oxygen, and electrons, and metal cations in the Group I metal salt are substituted with the hydrogen ions, while the generated metal cations move to the cathode through the ion-exchange membrane and the electrons move to the cathode through an external electric line; and in the cathode, carbon dioxide, water, metal cations, and electrons are reacted and produce carbonate and/or formate.

The present invention relates to an apparatus and method of preparing carbonate and/or formate from carbon dioxide. The apparatus of preparing carbonate and/or formate from carbon dioxide (CO.sub.2), comprising: an electrolysis reactor comprising (i) an anode which contains an aqueous solution of a Group I metal salt as an electrolytic solution, (ii) an ion-exchange membrane through which metal cations derived from the Group I metal salt and water flow from an anode to a cathode, (iii) a cathode, and (iv) a gas diffusion layer which supplies a carbon dioxide-containing gas to the cathode; a power supply unit of applying a voltage between the anode and the cathode; a first gas-liquid separator of recovering the electrolytic solution from the products formed in the anode; a second gas-liquid separator of recovering carbonate and/or formate from the products formed in the cathode; a pH meter of measuring the pH of the electrolytic solution recovered from the first gas-liquid separator; a first reactant supply unit of supplying (a) the electrolytic solution recovered from the first gas-liquid separator and (b) the aqueous solution of the Group I metal salt with which the recovered electrolytic solution is replenished according to the pH of the electrolytic solution, to the anode; and a second reactant supply unit of supplying carbon dioxide or a mixer comprising carbon dioxide and water vapor to the cathode; wherein, when a voltage is applied between the anode and the cathode, in the anode, water undergoes electrolysis to generate hydrogen ions, oxygen, and electrons, and metal cations in the Group I metal salt are substituted with the hydrogen ions, while the generated metal cations move to the cathode through the ion-exchange membrane and the electrons move to the cathode through an external electric line; and in the cathode, carbon dioxide, water, metal cations, and electrons are reacted and produce carbonate and/or formate.

A process for treating a source fluid in a manner that results in converting a carbon constituent into a carbonate constituent. The process includes the steps of providing the source fluid to a first treatment step, the source fluid being aqueous and comprising: at least one ppm to no more than five percent (by volume) of a hydrocarbonaceous component, and an impurity that includes a metal, a hard mineral, and combinations thereof. The process includes reacting the source fluid via the first treatment step to produce a treated aqueous stream comprising at least one percent to no more than thirty percent (by volume) of a hydroxide constituent.