The invention provides an inexpensive and scalable means to isolate commercially valuable metals from low quality raw materials with minimal capital expenditures. Metals are extracted from sized raw material using a lixiviant, such as an amine-based lixiviant, in a pond extractor. The liquid fraction containing solvated metal is separated from the extracted raw materials and exposed to an inexpensive and readily available source of carbon dioxide, such as unmodified atmospheric air and/or a flue gas. This precipitates the metal as a carbonate salt and regenerates the lixiviant, which is returned to the extraction step of the process following separation from the metal carbonates. Metal carbonates can be dried by simply arranging in exposed heaps, and in some embodiments further processed by kiln drying. Such methods can also be used to capture and sequester greenhouse gases such as carbon dioxide from the atmosphere.

The invention provides an inexpensive and scalable means to isolate commercially valuable metals from low quality raw materials with minimal capital expenditures. Metals are extracted from sized raw material using a lixiviant, such as an amine-based lixiviant, in a pond extractor. The liquid fraction containing solvated metal is separated from the extracted raw materials and exposed to an inexpensive and readily available source of carbon dioxide, such as unmodified atmospheric air and/or a flue gas. This precipitates the metal as a carbonate salt and regenerates the lixiviant, which is returned to the extraction step of the process following separation from the metal carbonates. Metal carbonates can be dried by simply arranging in exposed heaps, and in some embodiments further processed by kiln drying. Such methods can also be used to capture and sequester greenhouse gases such as carbon dioxide from the atmosphere.

Disclosed is a method for recycling metal-chelates by separating the metal or metal ion from the chelate by forming a metal salt or metal precipitate apart from the chelator. In various embodiments, gadolinium-chelates, which are used as MM contrast agent and which create vial hold-up material that is otherwise discarded, are acid or solvent treated to promote separation of the gadolinium from the chelate for downstream sale or further processing.

A method is provided for extracting scandium values from a scandium bearing laterite ore. The method includes providing a portion of a scandium bearing laterite ore having an average particle size of no more than 200 mesh, leaching the ore to produce a leachate, and recovering scandium values from the leachate.

A method is provided for extracting scandium values from a scandium bearing laterite ore. The method includes providing a portion of a scandium bearing laterite ore having an average particle size of no more than 200 mesh, leaching the ore to produce a leachate, and recovering scandium values from the leachate.

The present disclosure relates generally to systems and methods for recycling lead-acid batteries, and more specifically, relates to purifying and recycling the lead content from lead-acid batteries. A system includes a reactor that receives and mixes a lead-bearing material waste, a carboxylate source, and a recycled liquid component to form a leaching mixture yielding a lead carboxylate precipitate. The system also includes a phase separation device coupled to the reactor, wherein the phase separation device isolates the lead carboxylate precipitate from a liquid component of the leaching mixture. The system further includes a closed-loop liquid recycling system coupled to the phase separation device and to the reactor, wherein the closed-loop liquid recycling system receives the liquid component isolated by the phase separation device and recycles a substantial portion of the received liquid component back to the reactor as the recycled liquid component.

The present disclosure relates generally to systems and methods for recycling lead-acid batteries, and more specifically, relates to purifying and recycling the lead content from lead-acid batteries. A system includes a reactor that receives and mixes a lead-bearing material waste, a carboxylate source, and a recycled liquid component to form a leaching mixture yielding a lead carboxylate precipitate. The system also includes a phase separation device coupled to the reactor, wherein the phase separation device isolates the lead carboxylate precipitate from a liquid component of the leaching mixture. The system further includes a closed-loop liquid recycling system coupled to the phase separation device and to the reactor, wherein the closed-loop liquid recycling system receives the liquid component isolated by the phase separation device and recycles a substantial portion of the received liquid component back to the reactor as the recycled liquid component.

A stabilization process for an arsenic solution comprising thiosulfates, the process comprising: acidifying the arsenic solution to decompose the thiosulfates, to yield an acidified solution; oxidizing the acidified solution to oxidize residual As.sup.3+ to As.sup.5+ and reduced sulfur species to sulfates, to yield a slurry comprising elemental sulfur; separating elemental sulfur from the slurry to yield a liquid; oxidizing the liquid to oxidize residual reduced sulfur species, to yield an oxidized solution; and forming a stable arsenic compound from the oxidized solution.

A stabilization process for an arsenic solution comprising thiosulfates, the process comprising: acidifying the arsenic solution to decompose the thiosulfates, to yield an acidified solution; oxidizing the acidified solution to oxidize residual As.sup.3+ to As.sup.5+ and reduced sulfur species to sulfates, to yield a slurry comprising elemental sulfur; separating elemental sulfur from the slurry to yield a liquid; oxidizing the liquid to oxidize residual reduced sulfur species, to yield an oxidized solution; and forming a stable arsenic compound from the oxidized solution.

Systems for improving metal leach kinetics and metal recovery during atmospheric or substantially atmospheric leaching of a metal sulfide are disclosed. In some embodiments, an oxidative leach circuit 200 may employ Mechano-Chemcial/Physico-Chemical processing means for improving leach kinetics and/or metal recovery. In preferred embodiments, the Mechano-Chemcial/Physico-Chemical means comprises various combinations of stirred-tank reactors 202 and shear-tank reactors 212. As will be described herein, the stirred-tank reactors 202 and shear-tank reactors 212 may be arranged in series and/or in parallel with each other, without limitation. In some non-limiting embodiments, a shear-tank reactor 212 may also be disposed, in-situ, within a stirred-tank reactor 202.