A method for extracting secondary metal values from a sulfuric acid leachate is provided. The method includes providing a leachate which contains a primary metal and a plurality of secondary metals, wherein the primary metal is selected from the group consisting of Cu, Li and Ni and is derived from sulfuric acid leaching of an ore; passing the leachate through a first ion exchange resin which is selective to, and releasably binds, the plurality of secondary metals; stripping the plurality of secondary metals from the second or third ion exchange resins, thereby obtaining a first extract; and recovering the secondary metals from the first extract. In some embodiments, prior to passing the leachate through the first ion exchange resin, the leachate is passed through a second ion exchange resin which is selective to, and releasably binds, one of the plurality of secondary metals. The one of the secondary metals is then stripped from the second exchange resin, thereby obtaining a second extract, and the one of the secondary metals is recovered from the second extract.

The present invention relates to a process for the production of ammonium perrhenate (APR), which includes the use of Ca(OH)2 and to ammonium perrhenate which can be obtained by the method according to the invention.

A method for recovery of precious metals from copper anode slime may include leaching a leach liquor out of the copper anode slime by mixing the copper anode slime with a mixture of nitric acid and sulfuric acid, separating silver from the leach liquor by forming a silver chloride precipitate in the leach liquor by mixing a supersaturated sodium chloride solution with the leach liquor at room temperature and obtaining a first filtrate by filtering the silver chloride precipitate out of the leach liquor. Copper may be separated from the first filtrate by forming a copper hydroxide precipitate in the first filtrate by adjusting pH of the first filtrate at 9 and obtaining a second filtrate by filtering the copper hydroxide precipitate out of the first filtrate. Metallic selenium may be recovered from the second filtrate by reducing the metallic selenium via a chemical reduction utilizing L-ascorbic acid (LAA) as a reducing agent.

Method for the secondary fusion aluminum slags treatment to obtain finished goods for agricultural, domestic and industrial use includes treating aluminous material with concentrated sulfuric acid to obtain aluminum sulfate, wherein the aluminous material comes from slags fed in lots of finite-dimension in a treatment plant of aluminum slags and includes aluminum oxides present in at least 30% by weight, the method includes: a) a first step of separating the metals present in the slags, by known methodologies, to obtain powders of metals as Fe, Cu, Zn, Ni and to obtain an aluminous component in the form of aluminum grains; b) a subsequent step of treating the aluminous component, with sulfuric acid to obtain aluminum sulfate in solution and/or in form of crystals; c) a subsequent step of obtaining a solid residual portion, derived from step b), apt to be used as a refractory material in applications with thermal character.

Method for the secondary fusion aluminum slags treatment to obtain finished goods for agricultural, domestic and industrial use includes treating aluminous material with concentrated sulfuric acid to obtain aluminum sulfate, wherein the aluminous material comes from slags fed in lots of finite-dimension in a treatment plant of aluminum slags and includes aluminum oxides present in at least 30% by weight, the method includes: a) a first step of separating the metals present in the slags, by known methodologies, to obtain powders of metals as Fe, Cu, Zn, Ni and to obtain an aluminous component in the form of aluminum grains; b) a subsequent step of treating the aluminous component, with sulfuric acid to obtain aluminum sulfate in solution and/or in form of crystals; c) a subsequent step of obtaining a solid residual portion, derived from step b), apt to be used as a refractory material in applications with thermal character.

A process and system is provided for recovery of one or more metal values using solution extraction techniques and for metal value recovery. In an exemplary embodiment, the solution extraction system comprises a first solution extraction circuit and a second solution extraction circuit. A first metal-bearing solution is provided to the first and second circuit, and a second metal-bearing solution is provided to the first circuit. The first circuit produces a first rich electrolyte solution, which can be forwarded to primary metal value recovery, and a low-grade raffinate, which is forwarded to secondary metal value recovery. The second circuit produces a second rich electrolyte solution, which is also forwarded to primary metal value recovery. The first and second solution extraction circuits have independent organic phases and each circuit can operate independently of the other circuit.

A process and system is provided for recovery of one or more metal values using solution extraction techniques and for metal value recovery. In an exemplary embodiment, the solution extraction system comprises a first solution extraction circuit and a second solution extraction circuit. A first metal-bearing solution is provided to the first and second circuit, and a second metal-bearing solution is provided to the first circuit. The first circuit produces a first rich electrolyte solution, which can be forwarded to primary metal value recovery, and a low-grade raffinate, which is forwarded to secondary metal value recovery. The second circuit produces a second rich electrolyte solution, which is also forwarded to primary metal value recovery. The first and second solution extraction circuits have independent organic phases and each circuit can operate independently of the other circuit.

The invention relates to a method for preparing high-melting-point metal powder through multi-stage deep reduction, and belongs to the technical field of preparation of powder. The method includes the following steps of mixing dried high-melting-point metal oxide powder with magnesium powder and performing a self-propagating reaction, placing an intermediate product into a closed reaction kettle, leaching the intermediate product with hydrochloric acid as a leaching solution so as to obtain a low-valence oxide Me.sub.xO precursor of the low-valence high-melting-point metal; uniformly mixing the precursor with calcium powder, pressing the mixture, placing the pressed mixture into a vacuum reduction furnace, heating the vacuum reduction furnace to 700-1200 C., performing deep reduction for 1-6 h, leaching a deep reduction product with hydrochloric acid as a leaching solution and performing treatment, so as to obtain the high-melting-point metal powder.

The present invention discloses a prediction control method and system for component contents in a rare earth extraction process. The prediction control method includes: establishing an Elman neural network model of a rare earth extraction process; obtaining a predicted output value of the rare earth extraction process through the Elman neural network model of the rare earth extraction process; calculating an optimal set value through steady-state optimization; dynamically predicting an extractant flow increment and a detergent flow increment based on the predicted output value and the optimal set value; and controlling component contents in the rare earth extraction process according to the extractant flow increment and the detergent flow increment. According to the present invention, an optimal setting problem of a set point is solved through steady-state optimization calculation, and then an optimal control effect is achieved in combination with a dynamic prediction control method, thereby achieving optimal setting control over the component contents in the rare earth extraction process, and ensuring the product quality of the rare earth extraction process.

The present invention discloses a prediction control method and system for component contents in a rare earth extraction process. The prediction control method includes: establishing an Elman neural network model of a rare earth extraction process; obtaining a predicted output value of the rare earth extraction process through the Elman neural network model of the rare earth extraction process; calculating an optimal set value through steady-state optimization; dynamically predicting an extractant flow increment and a detergent flow increment based on the predicted output value and the optimal set value; and controlling component contents in the rare earth extraction process according to the extractant flow increment and the detergent flow increment. According to the present invention, an optimal setting problem of a set point is solved through steady-state optimization calculation, and then an optimal control effect is achieved in combination with a dynamic prediction control method, thereby achieving optimal setting control over the component contents in the rare earth extraction process, and ensuring the product quality of the rare earth extraction process.