Abstract: A process is provided for the production of magnesium from magnesium oxide, generally in the form of calcined dolomite, in which magnesium vapor is produced in a heated reaction zone from solid reactants fed substantially continuously to such reaction zone. The solid reactants include a reductant and optionally a slag forming agent, preferably ferrosilicon and alumina respectively. The reaction zone is heated by a thermal plasma, the electrical current of which includes the furnace bath as an integral part of it. The plasma forming gas is preferably argon.
Type:
Grant
Filed:
September 9, 1986
Date of Patent:
October 13, 1987
Assignee:
Council for Mineral Technology
Inventors:
Nicholas A. Barcza, Albert F. S. Schoukens
Abstract: A relatively solid, stable biomass reaction product is provided produced from microorganisms having metal uptake properties when contacted by an aqueous solution containing metal cations. The biomass reaction product is produced by treating cells thereof with a caustic solution, whereby the biomass reaction product after drying is characterized in the particulate state of having substantially enhanced uptake of metal cations from aqueous solutions as compared to the metal uptake property of the microorganism before treatment.
Type:
Grant
Filed:
September 20, 1985
Date of Patent:
September 1, 1987
Assignee:
Advanced Mineral Technologies, Inc.
Inventors:
James A. Brierley, Corale L. Brierley, Raymond F. Decker, George M. Goyak
Abstract: A method of regenerating strong-base anion exchange resins which have been used in the extraction of complex anions followed by elution with a thiocyanate strip solution is provided. The method involves the use of ferric ions in a regenerating solution together with a substitute anion for attachment of the resin, the regeneration taking place under conditions in which ferric-thiocyanate complex cations are formed and washed from the resin by the regenerating solution. The thiocyanate can be recovered by neutralizing the regenerating solution to precipitate ferric hydroxide and leave thiocyanate in solution.
Abstract: A method of treating ferromanganese alloys in a suitable reactor wherein the feed material is heated by a transferred-arc thermal plasma and is fed directly to the reactor bath. Accordingly, the molten bath defines a reaction zone and at least a part of the molten bath defines a lower electrode surface for the arc. In particular, ferromanganese alloy fines may be remelted to form a physically more massive form of the alloy and additionally may be refined by the addition of suitable metal oxides to yield a product wherein the content of at least silicon or carbon is lowered.
Abstract: A process for the extraction of metal values, in particular divalent metal ions such as copper, nickel, zinc, cobalt and manganese from aqueous solutions thereof which may be well in the acid range for example of pH 2 to 4. Extraction is effected using known organophosphorus or carboxylic acid extractants but in combination with non-chelating oximes, preferably of aldehydes wherein the alpha-carbon atom is primary or secondary. A synergistic effect between the extractant and oxime enables extraction to take place at a lower pH than heretofore thereby saving in acid and neutralizing agents in many instances.
Abstract: A thermal plasma generating electrode assembly of the type having a central, water-cooled electrode and an outer sheath defining therewith a path for gas is provided. The sheath is made as a non-water cooled sheath of a high melting, electrically conductive material to avoid damage to the electrode as a result of stray arcing by attracting such stray arcing to the sheath rather than the electrode. In addition the electrode can be retractable within the sheath to enable the latter to be employed for making initial electrical contact with the co-operating electrode of opposite polarity for the purposes of "striking" or initiating the arc upon start-up.
Abstract: A process for the production of ferrochromium by smelting chromite ore and in which ferrochromium fines may form a part of the feed materials, or for the further treatment of ferrochromium fines alone, in each case in the presence of a limited amount of carbonaceous reductant, is provided. The amount of reductant is generally limited to a maximum of 150% of the stoichiometric amount required for reduction of all the chromium and iron to metal or carbide form and to produce the required level of silicon in the product (normally 2 to 4%). The process is carried out by feeding the preferably premixed feed materials to a liquid slag phase in the bath of the furnace at a rate chosen to maintain the molten state and temperature of such material. Oxygen is substantially excluded from the reaction zone which is heated by a transferred arc thermal plasma.
Type:
Grant
Filed:
October 18, 1982
Date of Patent:
April 10, 1984
Assignees:
Council for Mineral Technology, Middelburg Steel and Alloys (Proprietary) Limited
Abstract: A process for the refining of high carbon ferrochromium metal in which the ferrochromium metal is refined, in the liquid state, with liquid metal oxide, generally including oxide fines. The heating is carried out in a transferred arc thermal plasma with substantial exclusion of carbon; although a consumable carbon electrode can be employed to generate the plasma. The ferrochromium metal is preferably premixed with the required oxides and fluxes and the feed is added to the furnace bath at a rate controlled to ensure that the slag and metal remain molten and at a chosen temperature.
Type:
Grant
Filed:
October 18, 1982
Date of Patent:
January 17, 1984
Assignees:
Council for Mineral Technology, Middleburg Steel and Alloys (Proprietary) Limited