The present invention provides an alkali metal and/or alkali earth metal extraction method that has excellent extraction efficiency and allows repeated use of an aqueous solution that extracts an alkali metal and/or alkali earth metal from a solid. The alkali metal and/or alkali earth metal extraction method is a method for extracting an alkali metal and/or alkali earth metal from a solid containing the alkali metal and/or alkali earth metal, the method including an elution step in which the solid is added to a neutral amino acid-containing aqueous solution or an amino acid-containing mixed aqueous solution produced by mixing a pH adjusting agent with an aqueous solution containing at least one of a neutral amino acid, an acidic amino acid and a basic amino acid so as to elute the alkali metal and/or alkali earth metal in the neutral amino acid-containing aqueous solution or the amino acid-containing mixed aqueous solution.

Hydrometallurgical systems, methods, and compositions are described in which organic amine-based lixiviants are utilized in the selective recovery of alkaline earth elements. The lixiviant can be regenerated and recycled for use in subsequent iterations of the process. Multiple alkaline earth elements can be recovered from a sample in parallel or in serial applications of the disclosed methods.

Hydrometallurgical systems, methods, and compositions are described in which organic amine-based lixiviants are utilized in the selective recovery of alkaline earth elements. The lixiviant can be regenerated and recycled for use in subsequent iterations of the process. Multiple alkaline earth elements can be recovered from a sample in parallel or in serial applications of the disclosed methods.

The present invention relates to an installation for the purification of minerals, pigments and/or fillers and/or the preparation of precipitated earth alkali carbonate and/or mineralization of water and to the use of such an installation for the purification of minerals, pigments and/or fillers and/or mineralization of water and/or the preparation of precipitated earth alkali carbonate.

The present invention relates to an installation for the purification of minerals, pigments and/or fillers and/or the preparation of precipitated earth alkali carbonate and/or mineralization of water and to the use of such an installation for the purification of minerals, pigments and/or fillers and/or mineralization of water and/or the preparation of precipitated earth alkali carbonate.

This invention provides a hydrometallurgical process for extracting one or more saleable products from a sulphate or chloride pregnant leach solution (PLS), or both. The products may be any one or more of the products selected from the group consisting of: precious metals including platinum group metals (PGMs), gold and silver, base metals, and rare metal elements, and metal cathodes, powders, salts or precipitates thereof; sulphur; hydrochloric acid (HCl); calcium; and silica.

This invention provides a hydrometallurgical process for extracting one or more saleable products from a sulphate or chloride pregnant leach solution (PLS), or both. The products may be any one or more of the products selected from the group consisting of: precious metals including platinum group metals (PGMs), gold and silver, base metals, and rare metal elements, and metal cathodes, powders, salts or precipitates thereof; sulphur; hydrochloric acid (HCl); calcium; and silica.

The present invention concerns a process for producing calcium carbonate from a calcium-containing alkaline slag material, the process containing the steps of extracting the alkaline slag material in a series of extraction steps, including at least 2 extraction steps, using extraction solvent(s) containing salt in an aqueous solution, whereby a calcium-containing filtrate and a residual slag is formed in each extraction step, separating the residual slag from the filtrate after each extraction step, carrying each residual slag to the following extraction in the series of extractions, to be used as raw material in said following extraction, and discarding the residual slag separated from the last extraction, carrying each filtrate to the previous extraction in the series of extractions, to be used as extraction solvent in said previous extraction, and carrying the first filtrate, separated from the first extraction step, to a carbonating step, carbonating calcium as calcium carbonate from the first filtrate, the first filtrate also used as the carbonation solvent, and using a carbonation gas, whereby calcium carbonate precipitates, separating and recovering the calcium carbonate from the remaining carbonation solvent, and recycling the remaining carbonation solvent to the last extraction step in the series of extraction steps, to be used as extraction solvent.

The present invention concerns a process for producing calcium carbonate from a calcium-containing alkaline slag material, the process containing the steps of extracting the alkaline slag material in a series of extraction steps, including at least 2 extraction steps, using extraction solvent(s) containing salt in an aqueous solution, whereby a calcium-containing filtrate and a residual slag is formed in each extraction step, separating the residual slag from the filtrate after each extraction step, carrying each residual slag to the following extraction in the series of extractions, to be used as raw material in said following extraction, and discarding the residual slag separated from the last extraction, carrying each filtrate to the previous extraction in the series of extractions, to be used as extraction solvent in said previous extraction, and carrying the first filtrate, separated from the first extraction step, to a carbonating step, carbonating calcium as calcium carbonate from the first filtrate, the first filtrate also used as the carbonation solvent, and using a carbonation gas, whereby calcium carbonate precipitates, separating and recovering the calcium carbonate from the remaining carbonation solvent, and recycling the remaining carbonation solvent to the last extraction step in the series of extraction steps, to be used as extraction solvent.

A method and system is provided to separate calcium carbonate inorganic eggshell from the inner lining of organic protein-based membrane in eggshell by-product. The method involves three phases: mechanical agitation/separation, functional chemical digestion and refining chemical digestion. In the mechanical stage, agitation and sieving are used to remove large pieces, and the majority of, membrane material. In the functional chemical digestion stage, the by-product is processed through at least one basic solution to remove additional organic membrane and impurities. In the refining chemical digestion stage, the remaining organic membrane and impurities are removed. The purified calcium carbonate is then rinsed and dried, in preparation for further refinement and processing to finished goods specifications.