Outotec Oyj

Outokumpu Oyj

Intune Circuits Oy

Olli Hyvärinen

Stig-Erik Hultholm

Pekka Taskinen

Matti Hämäläinen

Henri K Virtanen

Lauri Huhtasalo

Samuli Strömberg

Marko Hanhikorpi

Seppo Heimala

Liisa Haavanlammi

Marika Tiihonen

Michael H Barker

Jaakko Leppinen

Karri Osara

Tuija Suortti

Janne Karonen

Leo Lindroos

Olli Järvinen

Raimo Leimala

Marika Jyrälä

Tuula Hämäläinen, Legal Representative

Veikko Palosaari

Reijo Tontti

Damien Krebs

The invention relates to a method of forming an electrocatalytic surface on an electrode in a simple way, in particular on a lead anode used in the electrolytic recovery of metals. The catalytic coating is formed by a spraying method which does not essentially alter the characteristics of the coating powder during spraying. Transition metal oxides are used as the coating material. After the spray coating the electrode is ready for use without further treatment. The invention also relates to an electrode onto which an electrocatalytic surface is formed.

Method for forming an electrocatalytic surface on an electrode and the electrode

The invention relates to a method for recovering gold in connection with the hydrometallurgical production of copper from a waste or intermediate product containing sulphur and iron that is generated in the leaching of the copper raw material. The recovery of both copper and gold occurs in a chloride environment. The gold contained in the waste or intermediate is leached by means of divalent copper, oxygen and alkali bromide in a solution of copper (II) chloride and alkali chloride, in conditions where the oxygen-reduction potential is a maximum of 650 mV and the pH a minimum of 0.5. The bromide accelerates the dissolution of the gold.

Method for recovering gold

The invention relates to a method for recovering gold from a sulphidic concentrate, particularly one containing arsenopyrite and/or pyrite, hydro-metallurgically. The concentrate is first subjected to leaching with a concentrated solution of alkali chloride and copper (II) chloride, by means of which the copper minerals and some of the gold in the concentrate are made to dissolve. Elemental sulphur and precipitated iron and arsenic compounds are separated from the leaching residue using physical separation methods, whereby the first intermediate is obtained, which contains gold-bearing sulphide minerals and gangue minerals as well as the gold that remains undissolved. The free gold that remains undissolved is separated by means of gravity separation methods. After gravity separation, additional comminution is carried out, after which the sulphide minerals are decomposed and the gold-containing solution or residue is routed to the concentrate leaching circuit.

Method for the recovery of gold from sulphide concentrate

The invention relates to a method for the recovery of gold in connection with the hydrometallurgical production of copper from a residue or intermediate product containing sulphur and iron generated in the leaching of copper raw material. The recovery of both copper and gold takes place in a chloride milieu. The gold contained in the residue or intermediate product is leached using bivalent copper and oxygen in copper (II) chloride-sodium chloride solution in the conditions, where the oxidation-reduction potential is a maximum of 650 mV and the pH at least 1. The iron and sulphur contained in the residue remain for the most part undissolved.

Method for the recovery of gold

The invention relates to a method, by means of which the valuable metals contained in a sulphidic, multicomponent concentrate are recovered using hydrometallurgical treatment. One constituent of the concentrate is copper sulphide, which is leached using an alkali chloride-copper (II) chloride solution. The sulphides of other valuable metals, such as zinc, nickel, cobalt and lead are leached before copper leaching and each is recovered as a separate product before copper recovery.

Method for the hydrometallurgical treatment of sulfide concentrate containing several valuable metals

The method and furnace according to the invention enable a continuous processing of anode slime and are particularly suited to be connected to a process where anode slime is treated by hydrometallurgic methods after roasting. In the method according to the invention, the slime containing valuable metals and selenium is dried, roasted, sulfatized and cooled. The method includes steps to be carried out in succession, in continuous operation, so that the slime forms a slime layer on the conveyor and is conveyed to be treated in successive drying, roasting, sulfatizing and sulfuric acid removal and cooling units.

Method and device for treating anode slime

The invention relates to a method for removing silver from a chloride solution in a copper recovery process. According to this method, silver is removed using fine-grained copper powder and mercury. Silver removal occurs in at least two stages and mercury is fed into the solution at a certain molar ratio with regard to the silver in the solution.

Method for removal of silver from a copper chloride solution

The invention relates to a method for the recovery of metals, in particular copper, from a copper-bearing raw material, whereby the material is leached into a chloride-containing solution. The leaching of the raw material is performed oxidatively and at a sufficiently high redox potential that the copper in the copper chloride solution from leaching is mainly divalent. The chloride solution obtained, which contains copper and potentially other valuable metals, is fed to liquid-liquid extraction. In the extraction the copper is first transferred to the organic phase with extraction and then to a sulphate solution in stripping, which is fed to copper electrowinning.

Method for the recovery of metals using chloride leaching and extraction

The present invention relates to a method for manufacturing an electrically conductive pattern by printing a layer comprising metal oxide on a carrier substrate () and reducing the metal oxide to metal. The reduced layer is transferred to an application substrate (). The present invention also relates to the use of the method.

Method for manufacturing in electrically conductive pattern

The present invention focuses on the method for the removal of impurities, such as tellurium and bismuth, from gold concentrate containing sulfides. According to the present method, the impurities are leached from the gold concentrate with the aid of an acidic aqueous solution, at an elevated temperature, whereby the impurities dissolve and the gold remains in the concentrate.

Method of removal of impurities from gold concentrate containing sulfides

The invention relates to a method for producing copper in a hydrometallurgical process from copper-bearing raw materials, such as sulfidic concentrates. The concentrate is leached in a leaching stage of several steps into a chloride-based solution. The copper-bearing solution obtained from this leaching is subjected to reduction and solution purification, whereafter the copper contained in the solution is precipitated as copper oxidule by means of alkali hydroxide. The alkali chloride solution formed in the production of copper oxidule is fed into chloride alkali electrolysis, where it is regenerated back into alkali hydroxide. The hydrogen generated in the electrolysis is used in the reduction of copper oxidule and in other reduction stages of the process. The formed chlorine is used in the leaching of the raw material. When necessary, the reduced copper that is in a granular or pulverous form is further subjected to melting and casting in order to produce commercial-grade copper.

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Pori, Finland

Olli Hyvärinen