Abstract: The invention relates to a turbine-type high-power impeller, to be used for mixing slurry in hydrometallurgical process reactors. The impeller is formed of at least five blades, each of which blades comprises a front edge, trailing edge, root and tip; the roots of the impeller blades are permanently attached by a joint to the hub or axis of the impeller, so that the front edge of the impeller blade is straight, and the trailing edge is chamfered, in which case the blade is narrowed towards the tip, and the blade is provided with two longitudinal folds arranged in parallel with the front edge of the blade.

Abstract: A method and apparatus for converting an iron-bearing residue generated in a hydrometallurgical process that contains small amounts of soluble heavy metals into a stable form by means of a neutralizing agent. The residue is elutriated and the elutriated residue is fed into at least one stabilization or homogenization reactor, into which a neutralizing agent is also routed, and the homogenous mixing together of the residue and neutralizing agent takes place by means of a helix mixer, where the ratio of the diameter of the mixer to the diameter of the reactor is 0.75-0.99.

Abstract: A method and apparatus for converting an iron-bearing residue generated in a hydrometallurgical process that contains small amounts of soluble heavy metals into a stable form by means of a neutralising agent. The residue is elutriated and the elutriated residue is fed into at least one stabilisation or homogenisation reactor, into which a neutralising agent is also routed, and the homogenous mixing together of the residue and neutralising agent takes place by means of a helix mixer, where the ratio of the diameter of the mixer to the diameter of the reactor is 0.75-0.99.

Abstract: The invention relates to a method for leaching bulk concentrate of chalcopyrite-type by means of an aqueous solution containing sulphuric acid and an oxygen feed at atmospheric pressure and at a temperature between 75° C. and the boiling point of the solution. It is typical of the method that the particle size of the concentrate to be fed into leaching is in the region of 80% below 60-100 ?m and that the concentrate is leached with an aqueous solution, the acid concentration of which is regulated to be around 20-90 g/l.

Abstract: The invention relates to a turbine-type high-power impeller, to be used for mixing slurry in hydrometallurgical process reactors. The impeller is formed of at least five blades, each of which blades comprises a front edge, trailing edge, root and tip; the roots of the impeller blades are permanently attached by a joint to the hub or axis of the impeller, so that the front edge of the impeller blade is straight, and the trailing edge is chamfered, in which case the blade is narrowed towards the tip, and the blade is provided with two longitudinal folds arranged in parallel with the front edge of the blade.

Abstract: The invention relates to the use of a weakly acid cation exchange resin for chromatographic separation of carbohydrates. In the invention the hydrophilic/hydrophobic interaction of carbohydrates, sugars and sugar alcohols with the weakly acid cation exchange resin is utilized. The weakly acid cation exchange resin is used for separation of hydrophobic saccharides, such as deoxy, methyl and anhydrosugars and anhydrosugaralcohols from more hydrophilic saccharides.

Abstract: The invention relates to the use of a weakly acid cation exchange resin for chromatographic separation of carbohydrates. In the invention the hydrophilic/hydrophobic interaction of carbohydrates, sugars and sugar alcohols with the weakly acid cation exchange resin is utilised. The weakly acid cation exchange resin is used for separation of hydrophobic saccharides, such as deoxy, methyl and anhydrosugars and anhydrosugaralcohols from more hydrophilic saccharides.

Abstract: The invention relates to sulphonated polymer resins, particularly polymer resins with a sulphonated shell layer, and the preparation thereof. Resins according to the invention are prepared by sulphonating a polymer in a non-swollen state with substantially pure gaseous sulphur trioxide substantially in the shell layer of the polymer particles. The polymer to be sulphonated can be for example a styrene-DVB copolymer. The resins according to the invention can be used for example as chromatographic resins, ion-exchange resins and catalyst resins.