A method for recovering gold, silver, and/or platinum from components of a fuel cell stack of a fuel cell or electrolyzer includes treating the components with an aqueous electrolyte solution and with at least one gaseous oxidant in the fuel cell or the electrolyzer in an oxidation step. In a reduction step, the components are treated with a flow of an aqueous electrolyte solution and with at least one gaseous reductant in the fuel cell or the electrolyzer. A device by which the method can be carried out has a reservoir for the electrolyte solution, a line connected to an outlet opening of the reservoir, the line having a pump, an anode inlet connection connected to an anode inlet, and a cathode inlet connection connected to a cathode inlet. An oxidant-introducer introduces a gaseous oxidant into the line. A reductant-introducer introduces a gaseous reductant and/or inert gas into the line.

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.

An integrated refinery process for the disposal of metal-containing spent coked catalyst from hydrotreating and/or hydrocracking unit operations includes introducing the spent coked catalyst into a membrane wall gasification reactor in the form of flowable particles along with predetermined amounts of oxygen and steam based upon an analysis of the hydrocarbon content of the coke, and optionally, a liquid hydrocarbon; gasifying the feed to produce synthesis gas and a slag material; recovering and subjecting the slag material to further processes in preparation for a leaching step to solubilize and form one or more active phase metal compounds that are recovered from the leaching solution, either separately by sequential processing, or together. The recovered active metal compounds can be used, e.g., in preparing fresh catalyst for use in the refinery's hydroprocessing units.

A method for recovering noble metal from a heterogeneous catalyst comprising a solid carrier material and palladium, platinum or rhodium, present at least partially in elemental form, said method comprising the steps of converting the noble metal to an oxidation state>0 by treating the heterogeneous catalyst with an oxidizing agent in the presence of hydrochloric acid so as to form a two-phase system A comprising a hydrochloric aqueous phase A1 and a solid phase comprising the carrier material which is insoluble therein, optionally, at least partially separating the hydrochloric aqueous phase A1 from the two-phase system A and adding a further aqueous phase to the remaining residue of the two-phase system A so as to form a two-phase system B comprising a hydrochloric aqueous phase and a solid phase comprising the carrier material insoluble therein.

A method of selectively recovering palladium from a palladium-containing material comprises providing a leaching solution comprising hydrochloric acid, hydrogen peroxide, and an iron salt comprising one or both of ferric chloride or ferrous chloride and contacting a palladium-containing material with the leaching solution to dissolve palladium from the palladium-containing material. Related methods of selectively recovering palladium from a palladium-containing material are also disclosed.

A process for recycling and reusing supported Pd membranes includes the separation of the Pd (or Pd alloy) layer from the support by contacting the Pd membrane with hydrogen under pressure and at low temperature and then with a second gas that is different from hydrogen. The Pd layer separated from the support can then be treated to solubilize the Pd and, where appropriate, the alloy metal(s) to obtain salts that can be reused, for example in the preparation of new Pd membranes. The recovered supports are also reusable.

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.

Disclosed is a method for preparing a material of plant origin rich in phenolic acids, including at least one metal, including: preparing a material of plant origin chosen from: aquatic plants; materials rich in tannins; materials rich in lignin; and obtaining a material of plant origin, rich in phenolic acids, in which the ratio of the intensity of the vibration band of the CO bond of the COOH group and the intensity of each of the vibration bands the aromatic ring determined in FT-IR is between 0.5 and 4. The material of plant origin is brought into contact with an effluent including from 0.1 to 1000 mg/l of at least one metal, thus obtaining a material of plant origin rich in phenolic acids including from 1 to 30% by weight of at least one metal relative to the total weight of the material.

Disclosed is a method for preparing a solid material including manganese, the method including the following steps: a. bringing into contact an aqueous effluent including manganese, for example at least 5 mg/L, typically at least 5 to 50 mg/L, and preferably 7 to 25 mg/L of manganese, with an oxidizing agent, manganese, preferably at a temperature between 10 C. and 50 C., and obtaining an oxidized aqueous solution; b. adding a base to the oxidized aqueous solution obtained at the end of step a) until a pH of between 8 and 12, preferably greater than 9, and preferably from 9 to 10.5, and obtaining a solution including a precipitate; c. filtration of the solution obtained at the end of step b); and d. obtaining a solid material including manganese, and especially manganese (IV) and/or Mn (III).

A method for recovery of platinum group metals from a spent catalyst is described. The method includes crushing the spent catalyst to obtain a catalyst particulate material including particles having a predetermined grain size. The method includes subjecting the catalyst particulate material to a chlorinating treatment in the reaction zone at a predetermined temperature for a predetermined time period by putting the catalyst particulate material in contact with the chlorine containing gas. The method also includes applying an electromagnetic field to the chlorine-containing gas in the reaction zone to provide ionization of chlorine; thereby to cause a chemical reaction between platinum group metals and chlorine ions and provide a volatile platinum group metal-containing chloride product in the reaction zone. Following this, the volatile platinum group metal-containing chloride product is cooled to convert the product into solid phase platinum group metal-containing materials.