Abstract: A process to recover nickel, cobalt and copper by co-processing copper-containing sulphide concentrate feed containing one or more of arsenic, antimony, and bismuth, and laterite ore feed containing nickel and cobalt by pressure oxidative leaching. The sulphide concentrate and oxygen are controlled to produce sulphuric acid to leach nickel, cobalt, copper and acid soluble impurities into a liquid phase of an acidic leach slurry, to precipitate iron compounds and a majority of the arsenic, antimony and bismuth as solids, and to produce heat to heat the incoming feeds to a temperature above 230° C. Reacted slurry is withdrawn, solids are separated, and the PLS solution contains the nickel, cobalt, copper and acid soluble impurities. A first solution purification stage on the PLS neutralizes free acid, precipitates one or more of iron, aluminum, chromium and silicon, and, separates as solids, the precipitated impurities and other solids from a first purified solution.

Abstract: An integrated pressure leaching, heap leaching process for recovering copper from sulphidic feed containing iron, arsenic, and copper. Aqueous feed slurry of the sulphidic feed is pressure oxidized to form a liquid phase containing free sulphuric acid and aqueous copper sulphate, and to precipitate arsenic as solid iron arsenic compounds. Treated slurry is withdrawn from the pressure vessel and the liquid phase is separated from the solids. Copper is recovered from the separated liquid phase and generates a solution enriched in acid and depleted in copper. At least a portion of this solution is neutralized in a copper heap leach to produce a PLS containing copper and reduced in acid. At least a portion of the heap leach PLS is neutralized to produce a solution further reduced in acid, and solids containing copper precipitates, followed by a liquid solid separation.

Abstract: Process for recovering one or both of copper and silver from a sulphidic feed containing iron, arsenic, copper and silver by pressure oxidizing an aqueous feed slurry of the sulphidic feed in a pressure vessel to form a liquid phase containing free sulphuric acid and aqueous copper sulphate, and to precipitate arsenic as solid iron arsenic compounds. The process includes operating the pressure vessel at a sufficiently low solids content to maintain a free acid level below 30 g/L in the liquid phase, and providing sufficient heat to maintain a temperature in the pressure vessel above 200° C. Copper metal is recovered from the liquid phase and/or silver may be recovered from the solids by cyanide leaching without the need for a jarosite destruction step.

Abstract: Process to recover copper from a process feed including one or more feed components containing a base metal sulphidic feed, iron, copper and arsenic. Process feed and aqueous quench solution are introduced to a pressure oxidative leaching step with a partial pressure of oxygen above 200 kPa to form free sulphuric acid, to solubilize copper and other metal in the feed as aqueous sulphate compounds and to precipitate arsenic as solid iron arsenic compounds. A treated slurry comprising a liquid phase containing sulphuric acid and copper sulphate, and solids containing the iron arsenic compounds is withdrawn and the liquid phase is separated from the solids. To lessen arsenic re-dissolution and to maintain stability of the solid iron arsenic compounds, one or more of temperature, free acid level and residence time of the treated slurry is controlled. Copper metal is recovered from the separated liquid phase.

Abstract: Process to decrease silicon content of metal powder produced by hydrogen reduction from ammoniacal ammonium sulphate solutions containing metal ammine complexes, wherein metal (Me) is Ni, Co, or Cu. The process controls the precipitation of metal hydroxide, which is found to be an effective scavenger for silicon. Silicon is preferentially removed from metal diammine sulphate-containing solutions by precipitating with a small amount of a metal hydroxide, and then separating the silicon-bearing metal hydroxide precipitate from the solution. This solution, from which the silicon impurity has been removed with the metal hydroxide precipitate, can then be reduced in one or more densification cycles with a reducing gas to produce an elemental metal powder having a decreased silicon content. Alternatively, the solution is reduced to produce a low silicon metal powder seed material for the first of the one or more densification cycles.

Abstract: A process is provided to partially upgrade heavy oil using two or more reaction zones connected in series, each reaction zone being a continuous stirred tank maintained at hydrocracking conditions. The heavy oil feedstock and a solid particulate catalyst are stirred to form pumpable slurry which is heated to a target hydrocracking temperature and then continuously fed to the first reaction zone. Hydrogen is continuously introduced to the reaction zone to achieve hydrocracking and to produce a volatile vapor stream carried upwardly by the hydrogen to produce an overhead vapor stream. The hydrocracked heavy oil slurry from one reaction zone is fed to a next reaction zone also maintained under hydrocracking conditions with a continuous hydrogen feed to produce a volatile vapor stream. The overhead vapor stream from each reactor zone is continuously removed, and the hydrocracked heavy oil slurry from the last of the reaction zones is removed.

Abstract: Process for recovering one or both of copper and silver from a sulphidic feed containing iron, arsenic, copper and silver by pressure oxidizing an aqueous feed slurry of the sulphidic feed in a pressure vessel to form a liquid phase containing free sulphuric acid and aqueous copper sulphate, and to precipitate arsenic as solid iron arsenic compounds. The process includes operating the pressure vessel at a sufficiently low solids content to maintain a free acid level below 30 g/L in the liquid phase, and providing sufficient heat to maintain a temperature in the pressure vessel above 200° C. Copper metal is recovered from the liquid phase and/or silver may be recovered from the solids by cyanide leaching without the need for a jarosite destruction step.

Abstract: Process to decrease silicon content of metal powder produced by hydrogen reduction from ammoniacal ammonium sulphate solutions containing metal ammine complexes, wherein metal (Me) is Ni, Co, or Cu. The process controls the precipitation of metal hydroxide, which is found to be an effective scavenger for silicon. Silicon is preferentially removed from metal diammine sulphate-containing solutions by precipitating with a small amount of a metal hydroxide, and then separating the silicon-bearing metal hydroxide precipitate from the solution. This solution, from which the silicon impurity has been removed with the metal hydroxide precipitate, can then be reduced in one or more densification cycles with a reducing gas to produce an elemental metal powder having a decreased silicon content. Alternatively, the solution is reduced to produce a low silicon metal powder seed material for the first of the one or more densification cycles.

Abstract: Process to recover copper from a process feed including one or more feed components containing a base metal sulphidic feed, iron, copper and arsenic. Process feed and aqueous quench solution are introduced to a pressure oxidative leaching step with a partial pressure of oxygen above 200 kPa to form free sulphuric acid, to solubilize copper and other metal in the feed as aqueous sulphate compounds and to precipitate arsenic as solid iron arsenic compounds. A treated slurry comprising a liquid phase containing sulphuric acid and copper sulphate, and solids containing the iron arsenic compounds is withdrawn and the liquid phase is separated from the solids. To lessen arsenic re-dissolution and to maintain stability of the solid iron arsenic compounds, one or more of temperature, free acid level and residence time of the treated slurry is controlled. Copper metal is recovered from the separated liquid phase.

Abstract: Methods for recovering base metals, including, among other metals, molybdenum and nickel, from metal sulfides containing a Group VIB metal and a Group VIII metal. Generally, the methods comprise: contacting metal sulfides with a leaching solution containing ammonia and air to dissolve the metals into the leaching solution, forming a slurry containing soluble complexes of the metals, ammonium sulphate and solid residue containing ammonium metavanadate and any carbonaceous materials. The solid residue containing ammonium metavanadate and carbonaceous materials is then separated from the slurry and metal complexes are precipitated from the slurry by adjusting the pH. A second slurry may be formed comprising a second solid residue and a primary filtrate comprising ammonium sulfate solution that is substantially free of metals.

Abstract: There is provided a method of treating a metalliferrous material, comprising providing a metalliferrous material including at least one target metallic element, solubilising the metalliferrous material so as to effect production of an intermediate product including an operative solution. The operative solution includes a solvent component and a solute component. The solute component includes at least one solute component-based target metallic element and each one of the at least one solute component-based target metallic element corresponds to a one of the at least one target metallic element of the metalliferrous material such that the operative solution includes at least one target metallic element.

Abstract: A method of treating a metalliferrous material source is provided. The metalliferrous material source includes at least one of nickel sulphide and cobalt sulphide, and also includes iron sulphide. The metalliferrous material source is leached with a preliminary leachant in a leaching zone to effect production of a preliminary leach product including a preliminary leach solution and a preliminary leach solid residue. The preliminary leachant includes an aqueous solution comprising ammonia and ammonium sulphate. The preliminary leach solution includes at least one of dissolved nickel comprising material and dissolved cobalt comprising material. The preliminary leach solid residue includes: (i) at least one of nickel sulphide and cobalt sulphide, (ii) at least one of other nickel comprising material and other cobalt comprising material, and (iii) other iron comprising material.

Abstract: There is also provided a method of treating a metalliferrous material. The method includes providing a metalliferrous material including nickel, cobalt, and iron. At least a fraction of the metalliferrous material is leached with an aqueous solution including dissolved sulphuric acid and dissolved sulphur dioxide in a reaction zone so as to effect production of a leachant including nickel sulphate, cobalt sulphate, and iron sulphate. The leachant is contacted with a reagent material in a reaction zone, wherein the reagent material is aqueous ammonia solution, so as to effect production of a reaction product including a product solution component and a solid residue component. The nickel and cobalt are concentrated in the product solution component, and the iron is concentration in the solid residue component.

Abstract: There is provided an improvement in a process for producing cobalt (III) hexammine sulphate which process comprises oxidatively pressure leaching nickel cobalt sulphides in an ammoniacal ammonium sulphate solution. The nickel and cobalt sulphides are oxidized to sulphates, and an ammoniacal leach liquor in which dissolved cobalt is predominantly in the (III) oxidation state is produced. The ammoniacal leach liquor is combined with ammonia to precipitate the triple salt of cobalt (III) hexammine sulphate, nickel (II) hexammine and ammonium sulphate which is further treated to produce a crystalline cobalt (III) hexammine sulphate and a nickel enriched leach liquor. The improvement involves the provision of a second oxidative pressure treatment effective to maximize the formation of the desired cobalt (III) hexammine ion, prior to the triple salt precipitation step.

Abstract: A process for producing cobalt metal powder from nickel-cobalt sulphides wherein said nickel-cobalt sulphides are leached in an ammoniacal ammonium sulphate solution under an elevated pressure of an oxygen bearing gas, at a temperature of at least 80° C., with an effective ammonia to metals mole ratio in the range of 5:1 to 6.5:1 to oxidize the nickel and cobalt sulphides to sulphates, and to produce an ammoniacal leach liquor in which dissolved cobalt is predominantly in the (III) oxidation state, and an ammoniacal ammonium sulphate leach residue containing a cobalt (III) hexammine sulphate-calcium sulphate double salt.

Abstract: There is provided a process for the recovery of cobalt as cobalt (III) hexammine sulphate, comprising adding an effective amount of a calcium sulphate slurry to an ammoniacal ammonium sulphate solution containing cobalt (III) hexammine sulphate to thereby selectively precipitate a cobalt (III) hexammine sulphate-calcium sulphate double salt. The solution containing other base metal impurities is separated from the cobalt (III) hexammine sulphate-calcium sulphate double salt precipitate. An effective amount of an ammonium carbonate containing solution is added to the double salt precipitate to thereby redissolve cobalt (III) hexammine sulphate and precipitate calcium carbonate.