Described is a method of recovering a metal from a substrate having a metal sulphide, metal oxide, or combination thereof, by contacting the substrate with an aqueous oxidant to oxidize the metal sulphide to elemental sulphur and oxidized metal or convert the complex metal oxide to a metal salt, contacting the oxidized metal or simple metal oxide with ammonium hydroxide to form soluble a ammine complex of the metal to obtain a leachate and residual solids; separating the leachate from the residual solids; and recovering the metal.

The present invention relates to a species of genus Pseudomonas identified as Pseudomonas BR87641, termed Candidatus Pseudomonas pretiosorbens, having Accession Deposit Number DSM 33684.

The present invention is in the field of surfactants to extract a platinum group metal or gold, in particular palladium, from organic compositions. In particular, the invention concerns the use of surfactants to back-extract a platinum group metal or gold, in particular palladium, from organic compositions further comprising an extractant of said platinum group metal or gold, in particular palladium from an aqueous solution.

A method for the treatment of jarosite and other residues of the zinc and lead production industry, including the following steps: thermal treatment of the residues, at a temperature between 500? C. and 700? C., to obtain the evaporation of the imbibition water and the demolition of the jarosite molecule, resulting in the development of SO3 and in the removal of OH.sup.? groups to give additional water in the gaseous phase, and resulting in the obtainment, from the recondensation of these components, of an aqueous solution of diluted sulfuric acid, and with the simultaneous formation of a solid fraction composed of iron(III) oxide, zinc, lead, silver, copper sulphates and other minor elements; and then steps for acid leaching, a refining treatment; and purification to obtain solubilization of iron(III); separation of the solubilized iron(III) from the silica, which remains insolubilized; precipitation of iron(III) to obtain iron oxide pigment.

The present invention relates to a species of genus Pseudomonas identified as Pseudomonas BR87641, termed Candidatus Pseudomonas pretiosorbens, having Accession Deposit Number DSM 33684.

A method for the electrolytic production of pure copper from copper-containing compounds dissolved in a high-temperature bath of molten salts which function as an electrolyte in an electrolytic cell. An electric current is passed between an anode immersed in the copper-ion rich molten salt bath and a cathode or cathode-lined kettle in which the molten salt bath is contained, thereby reducing the dissolved copper ions to form pure molten copper. The deposited molten copper collects at the bottom of the kettle and can be separated from the molten salt bath using conventional means.

Process for removing inorganically- and/or organically-bound carbon from a precious metal-containing composition inside an oven chamber comprising at least one direct burner and at least one exhaust gas conduit, characterised by the sequence of steps of: a) providing a precious metal-containing composition comprising fractions of inorganically- and/or organically-bound carbon inside the oven chamber; b) closing the oven chamber; c) heating the content of the oven chamber by means of at least one direct burner in order to establish a temperature T1 in the range of 450 C. to 1,000 C. and maintaining temperature T1 for 5 min-48 h; whereby, once the oven chamber is closed, any gas exchange between the oven chamber and the surroundings can take place only via the at least one direct burner and the at least one exhaust gas conduit.

Process for digestion of fine iridium, comprising the steps of: (a) alkaline oxidative digestion of 1 part by weight fine iridium and 3 to 20 parts by weight of a combination comprising 40 to 70 parts by weight sodium hydroxide, 15 to 30 parts by weight sodium nitrate, and 10 to 40 parts by weight sodium peroxide in the melt, whereby the sum of the weight fractions adds up to 100 parts by weight; (b) cooling the digestion material formed in step (a) to 20 to 70 C.; (c) dissolving the acid-soluble fractions of the cooled digestion material in water/halogen hydracid until an acidic aqueous solution with a pH value in the range of 1 to +1 is obtained; and (d) boiling the acidic aqueous solution obtained in step (c) until the formation of nitrous gases is completed;

whereby a step (e) of separating insoluble ingredients from the acidic aqueous solution can take place before or after step (d), if needed.