A hydrometallurgical method for simultaneously extracting zinc, lead, silver, iron and calcium from electric arc furnace dust (hazardous waste) produced by the steelmaking industry (steelworks), in the form of industrial products: zinc as zinc sulphate or zinc cathodes; lead and silver as a concentrate of lead and silver; iron as reduced elemental iron for return to the electric arc furnace; and, lastly, calcium as gypsum, without solid waste or liquid effluents being generated relates to the chemical nature of the electric arc furnace dust (complex oxides) changes to a sulfide complex, and eliminating the hazards associated with the generation of fugitive heavy-metal salts. In addition, the hydrometallurgical problem of low recovery of zinc and iron is solved. Consequently, hydrometallurgy is made easier and more environmentally friendly, as condensed water is used as a leachate, the condensed water being continuously regenerated by vacuum evaporation systems without generating effluents.

A hydrometallurgical method for simultaneously extracting zinc, lead, silver, iron and calcium from electric arc furnace dust (hazardous waste) produced by the steelmaking industry (steelworks), in the form of industrial products: zinc as zinc sulphate or zinc cathodes; lead and silver as a concentrate of lead and silver; iron as reduced elemental iron for return to the electric arc furnace; and, lastly, calcium as gypsum, without solid waste or liquid effluents being generated relates to the chemical nature of the electric arc furnace dust (complex oxides) changes to a sulfide complex, and eliminating the hazards associated with the generation of fugitive heavy-metal salts. In addition, the hydrometallurgical problem of low recovery of zinc and iron is solved. Consequently, hydrometallurgy is made easier and more environmentally friendly, as condensed water is used as a leachate, the condensed water being continuously regenerated by vacuum evaporation systems without generating effluents.

A purification method that uses ion-selective ceramics to electrochemically filter waste products from a molten salt. The electrochemical method uses ion-conducting ceramics that are selective for the molten salt cations desired in the final purified melt, and selective against any contaminant ions. The method can be integrated into a slightly modified version of the electrochemical framework currently used in pyroprocessing of nuclear wastes.

A purification method that uses ion-selective ceramics to electrochemically filter waste products from a molten salt. The electrochemical method uses ion-conducting ceramics that are selective for the molten salt cations desired in the final purified melt, and selective against any contaminant ions. The method can be integrated into a slightly modified version of the electrochemical framework currently used in pyroprocessing of nuclear wastes.

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.

Disclosed herein are methods of using reactor outputs to purify materials. For example, methods of using acid and/or base produced in a reactor to purify materials (e.g., limestone, dolomite, waste streams, and/or ash) are described herein. Related systems are also described.

Disclosed herein are methods of using reactor outputs to purify materials. For example, methods of using acid and/or base produced in a reactor to purify materials (e.g., limestone, dolomite, waste streams, and/or ash) are described herein. Related systems are also described.

Hydrometallurgical systems, methods, and compositions are described in which organic amine-based lixiviants are utilized in the selective removal of carbonate-forming alkaline earth elements from slag. The resulting processed slag has a reduced tendency to form carbonate salts on environmental exposure, and reduced tendency to fracture due to the formation of such salts. The lixiviant used can be regenerated and recycled for use in subsequent iterations of the process.

Hydrometallurgical systems, methods, and compositions are described in which organic amine-based lixiviants are utilized in the selective removal of carbonate-forming alkaline earth elements from slag. The resulting processed slag has a reduced tendency to form carbonate salts on environmental exposure, and reduced tendency to fracture due to the formation of such salts. The lixiviant used can be regenerated and recycled for use in subsequent iterations of the process.