Processes for regenerating alkali process streams are disclosed herein, including streams containing sodium hydroxide, magnesium hydroxide, and combinations thereof. Systems for regenerating alkali process streams are disclosed herein, including streams containing sodium hydroxide, magnesium hydroxide, and combinations thereof.

The present invention refers to the recovery of high-value metals such as gold and silver from ores containing them by the leaching process that is carried out in tanks or reactors, and to the destruction of cyanide, which is carried out in cyanide destruction (detox) tanks at the end of the leaching process, to avoid damage to the environment. An oxygen diffuser with a specific design is provided which is used in pulp leaching tanks and in cyanide destruction (detox) tanks containing residual pulp, with the application of oxygen, whereby better results are obtained in the recovery of metals, in the application of oxygen and in retention time, among others.

The present disclosure relates to methods by which lead from spent lead-acid batteries may be extracted, purified, and used in the construction of new lead-acid batteries. A method includes: (A) forming a mixture including a carboxylate source and a lead-bearing material; (B) generating a first lead salt precipitate in the mixture as the carboxylate source reacts with the lead-bearing material; (C) increasing the pH of the mixture to dissolve the first lead salt precipitate; (D) isolating a liquid component of the mixture from one or more insoluble components of the mixture; (E) decreasing the pH of the liquid component of the mixture to generate a second lead salt precipitate; and (F) isolating the second lead salt precipitate from the liquid component of the mixture. Thereafter, the isolated lead salt precipitate may be converted to leady oxide for use in the manufacture of new lead-acid batteries.

The present disclosure relates to methods by which lead from spent lead-acid batteries may be extracted, purified, and used in the construction of new lead-acid batteries. A method includes: (A) forming a mixture including a carboxylate source and a lead-bearing material; (B) generating a first lead salt precipitate in the mixture as the carboxylate source reacts with the lead-bearing material; (C) increasing the pH of the mixture to dissolve the first lead salt precipitate; (D) isolating a liquid component of the mixture from one or more insoluble components of the mixture; (E) decreasing the pH of the liquid component of the mixture to generate a second lead salt precipitate; and (F) isolating the second lead salt precipitate from the liquid component of the mixture. Thereafter, the isolated lead salt precipitate may be converted to leady oxide for use in the manufacture of new lead-acid batteries.

The present invention relates to separation and recovery of metals from ground alkaline batteries using anode mud (zinc electrolysis waste) and other manganese and zinc containing materials. The material commonly referred to as alkaline black (AKB) is solubilized into sulfate media and the manganese to zinc ratio is adjusted. The solution containing metals is processed using crystallization and ion exchange methods to produce manganese sulfate and zinc sulfate solutions for several possible applications.

A method of recovering rare earth elements and other trace metals from based ores can include providing a body of rubblized carbon-based ore. The rubblized carbon-based ore can include carbonates and rare earth elements. The carbonates in the ore can be decomposed at an elevated decomposition temperature and an oxygen deficient atmosphere to form an enriched spent ore and carbon dioxide.

A method of recovering rare earth elements and other trace metals from based ores can include providing a body of rubblized carbon-based ore. The rubblized carbon-based ore can include carbonates and rare earth elements. The carbonates in the ore can be decomposed at an elevated decomposition temperature and an oxygen deficient atmosphere to form an enriched spent ore and carbon dioxide.

The present invention relates to metallurgical processes, and more particularly to a process for producing titaniferous feedstock and fines, a process for agglomerating titaniferous fines, and a process for producing titaniferous metals and titaniferous alloys. Recovery of rare-earth, vanadium and scandium from titanium iron bearing resources is also disclosed. Selective leaching for Scandium recovery from all magnetite type resources such as ilmenite, ferro titanic resources, nickel laterites, magnetite iron resources etc.

A method for dissolving a lithium compound according to the present invention includes bringing a lithium compound into contact with water or an acidic solution, and feeding, separately from the lithium compound, a carbonate ion to the water or the acidic solution to produce carbonic acid, and allowing the carbonic acid to react with the lithium compound to produce lithium hydrogen carbonate.

A method for cleanly extracting metallic silver includes: mixing an acidic solution containing Ce.sup.4+ and NO.sub.3.sup.− with a silver-containing material for leaching; after the leaching is completed, carrying out a solid-liquid separation to obtain a leaching solution containing Ce.sup.3+ and Ag.sup.+; and electrolyzing the leaching solution, wherein an oxidation reaction of Ce.sup.3+ occurs at an anode to realize a regeneration of Ce.sup.4+ and an electrolytic reduction occurs at a cathode to reduce Ag.sup.+ to obtain the metallic silver. Ce.sup.4+ is used as a leaching agent and an intermediate oxidant to implement a cyclic operation of solution leaching and electrolytic regeneration on the silver-containing material. Almost no NO.sub.x and waste liquid are caused by the extraction process, and the invention is clean and environmentally friendly.