Abstract: A method for recovering NiSO4.6H2O crystals from a nickel rich organic phase is provided. The method includes contacting a nickel rich organic phase with an aqueous strip solution of sufficient H2SO4 concentration to extract nickel from the organic phase and of sufficient Ni2+ concentration to precipitate NiSO4.6H2O crystals and form a nickel lean organic phase. Also provided are methods for recovering NiSO4.6H2O crystals that include preceding processing steps, including low temperature pressure oxidation (LTPOX) autoclaving of a nickel sulphide concentrate to afford a pregnant leach solution (PLS).

Abstract: Disclosed in the present invention is a method for preparing nickel sulfate from a nickel-iron-copper alloy. The method comprises: in a high-pressure oxygen environment, mixing a nickel-iron-copper alloy crushed material, aqueous ammonia, ammonium sulphate, and a corrosion assisting agent, leaching, then performing solid-liquid separation on the leached slurry, adding a precipitant into a filtrate, and performing ammonia distillation to obtain a nickel-containing leachate; then adding an extractant into the nickel-containing leachate to extract nickel so as to obtain a nickel-containing extraction organic phase; and then adding sulfuric acid into the nickel-containing extraction organic phase to perform back extraction of nickel so as to obtain a nickel sulfate solution.

Abstract: Disclosed are novel, as-crystallized RHO zeolite compositions with improved uniformity in morphology. These RHO compositions are useful for preparing cation-exchanged RHO zeolites that can be used as adsorbents for oxygen and/or nitrogen with improved properties. The adsorbents can be used in pressure swing adsorption processes for selectively adsorbing oxygen and/or nitrogen from feed streams such as an air stream or crude argon stream. Also disclosed are novel methods of preparing RHO zeolites with improved morphology control.

Abstract: A process for the recovery of nickel and cobalt from nickel and cobalt containing ores, including the steps of first leaching a laterite ore and/or a partially oxidized sulfide ore with an acid solution to produce a pregnant leach solution containing at least dissolved nickel, cobalt and ferric ions, and subsequently leaching a sulfide ore or concentrate with the pregnant leach solution to produce a product liquor. Alternatively, the laterite ore and/or partially oxidized sulfide ore can be leached in a combined leach with the sulfide ore or concentrate. The ferric ion content in the pregnant leach solution or in the combined leach is sufficient to maintain the oxidation and reduction potential in the sulfide leach high enough to assist in leaching nickel from the sulfide ore or concentrate.

Abstract: A process for treating a finely particulate, in particular metal-containing, charge material: The charge material and a treatment gas, in particular a reduction gas, are introduced into a fluidized bed chamber of a fluidized bed reactor to form a fluidized bed. After at least partial reaction in the fluidized bed, the treatment gas is discharged from the fluidized bed and, outside the fluidized bed, is at least partially reprocessed, preferably oxidized, by an exothermic, chemical reaction with a reactant, preferably with a gaseous and/or liquid oxidizing agent. The thermal energy of this reaction is at least partially introduced into the fluidized bed chamber, in particular into the fluidized bed, or being discharged therefrom to affect the temperature of the particulate material above the bed. Also an apparatus for operating such a fluidized bed includes the chamber, lines into and out of the chamber for gas and material and a cyclone at the chamber for the material.

Abstract: A method for converting nickel into a nickel salt solution. Nickel is dissolved and reacted in an oxygen-enriched acidic solution to produce a nickel salt solution as illustrated in the following chemical equation, wherein X is a conjugate base: Ni+H2X+½O2->NiX+H2O.

Abstract: A process for leaching a value metal from a base metal sulfide ore, comprising the step of leaching the ore with a lixiviant comprising a chloride, an oxidant and hydrochloric acid is disclosed. The leaching is controlled, by use of low concentrations of hydrochloric acid and a redox potential, to effect formation of hydrogen sulfide from the base metal sulfide ore. The hydrogen sulfide is stripped from the leach solution, thereby reducing the amount of sulfate generated in the leach to very low levels. The leaching may also be conducted to limit the co-dissolution of platinum group metals and gold with the base value metals. The leach forms a value metal-rich leachate and a solids residue. The solids residue may be subsequently leached to recover the platinum group metals and gold. The value metal-rich leachate can be is oxidized and neutralized to recover the value base metals. In an embodiment, the chloride is magnesium chloride and lixiviant solution is regenerated.

Abstract: A process for the oxidative leaching of sulphide mineral species, the method characterized by the method steps of: leaching a slurry containing the mineral species in one or more reaction vessels; circulating a stream of leach liquor to a flash cooler; flashing the liquor in the flash cooler at a pressure less than atmospheric pressure so as to dissipate heat; and recirculating the liquor to the or each reaction vessel.

Abstract: A hydrometallurgical process based on pressure leaching at elevated temperature for recovering nickel from nickel oxide ores, characterized by a simplified and efficient process as a whole, realizing a simplified leaching stage, reduced neutralizer consumption and precipitate production in the neutralization stage, and efficient use of recycled water. The hydrometallurgical process of the present invention, comprising a leaching stage which stirs the slurried ore in the presence of sulfuric acid at 220 to 280° C.

Abstract: A process for the extraction of a base metal such as Ni, Co or Zn, from suiphide ore or concentrate containing copper and the base metal comprises the step of subjecting the ore or concentrate to pressure oxidation in the presence of oxygen and an acidic solution containing halide and sulphate ions to produce a product solution containing copper and the base metal. The product solution is subjected to a copper extraction process for recovering copper from the solution and the product solution containing the base metal after copper recovery is recirculated for recycled to the pressure oxidation to effect build-up of the base metal in the product solution. Preferably, a stream which is split from the product solution is treated for the recovery of the base metal.

Abstract: A preferred embodiment of the present invention provides a process for making nickel sulfate by converting nickel metal into nickel sulfate, which may be converted to nickel hydroxide. Nickel metal is dissolved in sulfuric acid and oxygen containing gas is introduced to produce a nickel sulfate solution having nickel sulfate and water as illustrated in the following chemical equation. Ni+H2SO4+½O2?NiSO4+H2O The nickel sulfate is filtered and sulfuric acid is continually added to maintain stoichiometry within a reactor until the nickel metal is dissolved. The sulfuric acid, oxygen containing gas and nickel metal may be heated to facilitate the desired reaction. Then, the nickel sulfate may be utilized to produce nickel hydroxide.

Abstract: A process for the oxidative leaching of sulphide mineral species, the method characterised by the method steps of: leaching a slurry containing the mineral species in one or more reaction vessels; circulating a stream of leach liquor to a flash cooler; flashing the liquor in the flash cooler at a pressure less than atmospheric pressure so as to dissipate heat; and recirculating the liquor to the or each reaction vessel.

Abstract: A process for the recovery of nickel and/or cobalt values from a concentrate containing nickel or cobalt hydroxide comprises the steps of subjecting the concentrate to a leaching stage with an ammonium solution to produce a leach solution containing nickel and/or cobalt values and a residue. The nickel concentration in the leach solution is controlled to a maximum value of about 3 to 25 g/l, preferably 8 to 15 g/l and more preferably 10 g/l.

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.