Patent classifications
C22B11/00
Extraction of selected platinum-group metals from supported catalyst
Disclosed herein is a method for extracting precious metals from supported catalysts. The precious metal in one embodiment is rhodium. The supported catalyst may be from equipment, such as a used catalytic converter. The method is carried out at low temperature, and does not require harsh conditions, such as the use of a strong acid. The method involves contacting the catalytic material with a polar molecule and a reactive gas.
METHOD OF RECOVERING MATERIALS BOUND TO A METALLIC SUBSTRATE USING CRYOGENIC COOLING AND AN AQUEOUS SOLUTION
A recycling process that facilitates separation of materials from metallic substrates by cryogenically cooling the recyclable items to induce embrittlement of the metals. Embrittled metals may be shattered more efficiently and with a higher yield of materials bound to the metallic substrates. Metal embrittlement may be induced by mixing the source stream with liquid nitrogen, and cooling the stream to approximately minus 200° F. Multiple recovery stages may be employed to maximize the yield of the target materials. Embodiments may enable recovery of platinum group metals (PGMs) from catalytic converters with metallic foil substrates. Yield of PGMs may be enhanced by employing a primary recovery stage and a secondary recovery stage, by cryogenically cooling input materials for each stage, by mixing the pulverized material in secondary recovery with an aqueous solution to dissipate attractive charges, and by wet screening the pulverized material slurry to obtain the PGM particles.
Method for whole component microwave fast digestion and precious metal extraction from ionic liquid of waste circuit board
The invention discloses Method for whole component microwave fast digestion and precious metal extraction from ionic liquid of waste circuit board, and belongs to the field of hydrometallurgy. Based on the theory that microwaves can directly penetrate through a leaching medium to directly heat a circuit board, microwave-assisted leaching can reinforce mass transfer and heat transfer in the traditional leaching process, the leaching time is greatly shortened, and the leaching efficiency is improved. Before leaching, a waste circuit board does not need to be smashed, and environmental protection is achieved while energy is saved. The temperature rising process and reaction time of the reaction can be controlled, the whole process is conducted under the airtight condition, heat loss in the leaching process is avoided, the valuable leaching rate is high, the selectivity is high, and efficient leaching of valuable metal can be achieved. Precious metal leachate is extracted through imidazolium ionic liquid, the selectivity of the imidazolium ionic liquid to gold is high, and the co-extraction phenomenon of gold, nickel, copper and other ions is avoided. The method for extracting the precious metal leachate through ionic liquid is a green and clean recycling method, and the overall recycling rate of gold, nickel and copper can reach 99% or above
Method of separating grains of valuable minerals, precious metals, rare-earth metals, precious and semi-precious stones from natural ores in the aquatic environment by means of the phenomenon of adhesion.
A method of separating grains of valuable minerals, precious metals, rare-earth metals, precious and semi-precious stones from natural ores in the aquatic environment by means of the phenomenon of adhesion, consecutively covering stages such as: initial separation consisting in sieving fractions up to 5000 μm from alluvial (rubble) ore or crushing primary (rock) ore to a fraction causing the separation of valuable minerals from gangue and where appropriate separating ferromagnetics from ores by means of a known method; forming the suspension by mixing the initially separated fraction of ore with liquid; adsorption of valuable minerals from the suspension on the adhesive coating and also recovering water from the process; and desorption of particles of valuable minerals from the adhesive coating; wherein lanolin or its mixtures with additives are used to form the adhesive coating in the separator, whereby, the content of lanolin in the mixture is not less than 80%.
Method of oxidative leaching of sulfide ores and/or concentrates
A method for leaching one or more target metals from a sulfide ore and/or concentrate containing such, the method comprising the steps of: (a) Exposing the ore and/or concentrate to an aqueous solution of chlorine-based oxidising species in which the hypochlorous acid comprises at least 10 mol % of the chlorine-based oxidising species; (b) Allowing and/or facilitating the oxidation of the target metals by the hypochlorous acid, thereby decreasing the pH such that the predominant chlorine-based oxidising species becomes chlorine; (c) Allowing and/or facilitating the oxidation of the target metals by the chlorine; (d) Allowing and/or facilitating the dissolution of the target metals by the solution species formed during the oxidation by hypochlorous acid and/or chlorine; and (e) Passing the pregnant solution produced thereby to a means for metal recovery.
Method for recovering ruthenium from spent ruthenium-based catalyst carried on aluminum oxide
A method for recovering ruthenium from a spent ruthenium-based catalyst carried on aluminum oxide includes: drying, calcining, and cooling a spent catalyst; grinding the spent catalyst into black powder; placing the black powder in a fluidized bed reactor, purging the reactor with hydrogen and heating the black powder to obtain ruthenium metal, then heating the black powder in a mixed atmosphere of oxygen and ozone to obtain RuO.sub.4 gas; absorbing the RuO.sub.4 gas with a sufficient amount of hydrochloric acid to obtain a H.sub.3RuCl.sub.6 solution; adding an excess oxidant to the H.sub.3RuCl.sub.6 solution to oxidize the H.sub.3RuCl.sub.6 into H.sub.2RuCl.sub.6; adding excess NH.sub.4Cl to the H.sub.2RuCl.sub.6 and then filtering, and washing the filter cake to obtain solid (NH.sub.4).sub.2RuCl.sub.6; and reducing the solid (NH.sub.4).sub.2RuCl.sub.6 by hydrogen to obtain ruthenium metal.
SIMPLIFIED METHOD OF GOLD RECOVERY FROM ELECTRONIC WASTE
The present invention related to generally to a process to recover metals from waste electronics, and more particularly a process to recover gold from waste electronics. The gold is first delaminated in a first step using a solution containing a weak acid in combination with an oxidizer. The second step isolates and purifies the delaminated gold from the chip debris using solvents, water and a wetting agent/surfactant. The proposed two step method of gold recovery from electronic waste is effective without the need for strong or costly chemicals or leaching.
METHOD FOR RECYCLING SILVER PRESENT ON A PHOTOVOLTAIC CELL
A method for recycling silver present on a photovoltaic cell comprising: —a step a) of supplying a photovoltaic cell including —a support substrate made of silicon, —an upper layer of doped silicon arranged on the support substrate, —a plurality of silver lines arranged on the upper layer, —at least one anti-reflective layer arranged on the upper layer and adjacent to the silver lines; —a step b) of etching the anti-reflective layer by immersing the photovoltaic cell in an acid solution; —a step c) of etching the upper layer by immersing the photovoltaic cell without an anti-reflective layer in a basic solution, leading to the separation of the silver lines; —a step d) of drying the assembly formed by the support substrate and the separated silver lines; —a step e) of extracting the silver lines in the solid state.
METHOD FOR THE RECOVERY OF PALLADIUM
The present invention relates to a method for the recovery of palladium from an aqueous solution, comprising the steps of: (A) providing a dispersion comprising an aqueous dispersing phase comprising palladium(II), at least one non-ionic surfactant and at least one compound bearing a beta-dithiocarbonyl group, so as to form a hydrophobic complex of palladium(II) with the compound bearing a beta-dithiocarbonyl group; (B) heating the dispersion resulting from step (A) to a temperature at least equal to its cloud point so as to obtain the phase separation between the aqueous dispersing phase and a dispersed phase rich in surfactant comprising at least a part of said hydrophobic complex; (C) separating the dispersed phase rich in surfactant from the aqueous dispersing phase resulting from step (B); and (D) recovering the hydrophobic complex of palladium(II) with the compound bearing a beta-dithiocarbonyl group.
Beneficiation of values from ores with a heap leach process
This invention relates to a process for recovering value metals from sulphide ore, including steps of crushing ore in a primary crusher (14) to a size of about 40 cm and less, passing the crushed ore through one or more of the following pre-beneficiation processes such as bulk sorting (16) and screening (20) followed by coarse floatation (46/50), or gravity separation or magnetic separation. A waste stream (54) from the pre-beneficiation process/es with a particle size greater than 100 μm is stacked in a heap (26) and subjected to a heap leach. This integrated process utilises the pre-beneficiation techniques best suited to the characteristics of a particular orebody; and during the pre-beneficiation simultaneously creating a low grade stream that yields significantly higher recoveries than achievable by normal heap leaching of low grade run of mine ore.