Digestion of impure alumina with sulfuric acid dissolves all constituents except silica. Resulting sulfates, produced from contaminants in the impure alumina, remain in solution at approximately 90 C. Hot filtration separates silica. Solution flow over metallic iron reduces ferric sulfate to ferrous sulfate. Controlled ammonia addition promotes hydrolysis and precipitation of hydrated titania from titanyl sulfate that is removed by filtration. Addition of ammonium sulfate forms ferrous ammonium sulfate and ammonium aluminum sulfate solutions. Alum is preferentially separated by crystallization. Addition of ammonium bicarbonate to ammonium alum solution precipitates ammonium aluminum carbonate which may be heated to produce alumina, ammonia, and carbon dioxide. The remaining iron rich liquor also contains magnesium sulfate. Addition of oxalic acid generates insoluble ferrous oxalate which is thermally decomposed to ferrous oxide. Carbon monoxide reduces the ferrous oxide to metallic iron. Further oxalic acid addition precipitates magnesium oxalate which is thermally decomposed to magnesium oxide.

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 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-beating 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 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.

Jacketed rotary converter. The converter includes an inclined pot mounted for rotation about a longitudinal axis, a refractory lining for holding a molten alloy pool, an opening in a top of the pot for introducing feed, a lance for injecting oxygen-containing gas, a heat transfer jacket for the pot adjacent the refractory lining, and a coolant system to circulate a heat transfer medium through the jacket to remove heat from the alloy pool in thermal communication with the refractory lining. Also disclosed is a PGM converting process using the jacketed rotary converter. The process can also include low-or no-flux converting; refractory protectant addition; slag separation; partial feed pre-oxidation; staged slagging; and/or smelting the slag in a secondary furnace with primary furnace slag.

A method for recycling a material may include carrying out a first pass operation. The first pass operation may include preparing an E-waste material and a solid oxide material. The E-waste material may include Fe and Si. The first pass operation may include blending the E-waste material with fluxing agents. The first pass operation may include feeding a furnace with the blended E-waste material and the solid oxide material. The method may include smelting the blended E-waste material and the solid oxide material from the first pass operation to obtain a slag. The slag may include iron oxide and a molten metal. The molten metal may include copper.

Integrated PGM converting process. The process includes smelting a catalyst material in a primary furnace, smelting the primary furnace slag in a secondary furnace, converting the collector alloys from the primary and secondary furnaces in a converter to recover PGM enriched alloy and converter slag, separating the recovered converter slag into first and second converter slag portions, and supplying the first converter slag portion to the secondary furnace for smelting with the primary furnace slag. The process can also include low- or no-flux converting; refractory protectant addition; magnetic slag separation; partial feed pre-oxidation; staged slagging; and/or jacketing the converter.

The process includes melting an initial collector alloy charge to start a converter cycle, introducing feed and injecting oxygen into the alloy pool, allowing ferrous slag to collect, terminating feed introduction and oxygen injection to tap the slag, repeating the feed introduction/oxygen injection/slag tapping sequence a plurality of times, and then tapping the alloy to end the cycle. A delay before non-final slag tappings allows any entrained alloy to settle back into the alloy pool, but the final slag tapping is commenced promptly and alloy is optionally entrained. Slag from the final tapping that may contain entrained alloy can be recycled to the converter, e.g., in a subsequent cycle. The process can also include low- or no-flux converting; refractory protectant addition; slag separation; partial feed pre-oxidation; smelting the slag in a secondary furnace with primary furnace slag; and/or jacketing the converter.

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.

Converting process with slag separation and recycle to the converter. The process includes introducing converter feed into the pot holding a molten alloy pool, oxygen injection into the pool, tapping the slag, and tapping the PGM-enriched alloy. The collector alloy contains no less than 0.5 wt % PGM, 40 wt % iron, and 0.5 wt % nickel, and no more than 3 wt % sulfur and 3 wt % copper, and the recovered slag is separated into recycle and non-recycle portions. The recycle slag portion preferably contains more PGM than the non-recycle portion. The process can also include low- or no-flux converting; using a refractory protectant in the converter; magnetic separation of slag; partial pre-oxidation of the converter feed; smelting catalyst material in a primary furnace to produce the collector alloy; and/or smelting the converter slag in a secondary furnace with slag from the primary furnace.