Abstract: Digestion of impure alumina with sulfuric acid dissolves all constituents except silica. Resulting sulfates, produced from contaminants in the impure alumina, remain in solution at approximately 90° C. Hot filtration separates silica. Solution flow over metallic iron reduces ferric sulfate to ferrous sulfate. Controlled ammonia addition promotes hydrolysis and precipitation of hydrated titania from titanyl sulfate that is removed by filtration. Addition of ammonium sulfate forms ferrous ammonium sulfate and ammonium aluminum sulfate solutions. Alum is preferentially separated by crystallization. Addition of ammonium bicarbonate to ammonium alum solution precipitates ammonium aluminum carbonate which may be heated to produce alumina, ammonia, and carbon dioxide. The remaining iron rich liquor also contains magnesium sulfate. Addition of oxalic acid generates insoluble ferrous oxalate which is thermally decomposed to ferrous oxide. Carbon monoxide reduces the ferrous oxide to metallic iron.

Abstract: Extracting gallium and/or arsenic from materials comprising gallium arsenide is generally disclosed. In some example embodiments, a material comprising gallium arsenide may be exposed to a first heating condition to form a first exhaust. The first exhaust may be directed to an arsenic collection bed including aluminum, which may form aluminum arsenide. The material including gallium arsenide may be exposed to a second heating condition and/or a vacuum may be applied, which may form a second exhaust. The second exhaust may be directed to a gallium collection bed including aluminum, which may form gallium alloys of aluminum.

Abstract: A method for processing converter slag produced in copper smelting includes feeding the converter slag into a reducing furnace, reducing zinc and copper contained in the converter slag by heating and removing the reduced zinc through volatilization in a reducing furnace. The slag discharged from the converter is transformed into a raw material for iron making.

Abstract: A method of recovering titanium dioxide from a raw material additionally containing aluminium includes the steps of grinding the titanium dioxide raw material, reacting the particulate raw feed material with sulphuric acid under specified conditions, digesting and filtering the resultant cake material containing titanyl sulphate, if present, treating the solution to remove calcium and/or iron, precipitating out the aluminium as aluminium ammonium sulphate, hydrolysing the remaining titanyl sulphate solution and, after washing the hydrolysate, calcining the hydrolysate to produce titanium dioxide.

Abstract: Disclosed herein is a method for economically manufacturing high quality TiC powder, TiCN powder or ultrafine nanophase TiC+Ni (Co, Al) and TiCN+Ni (Co, Al) composite powders by means of metallothermic reduction. The method comprises the steps of preparing a starting solution of titanium tetrachloride (TiCl4) in a carbon chloride, feeding the starting solution into a closed container containing molten magnesium (Mg) under inert atmosphere, vacuum-separating unreacted liquid-phase Mg and magnesium chloride (MgCl2) remaining after reduction of magnesium from the closed container, and collecting a TiC compound from the closed container.

Abstract: A process for the recovery of gold and the platinum group metals from sources that contain relatively low amounts of the metals is described. The process is environmentally acceptable and uses no expensive and potentially dangerous organic solvents.

Abstract: The present invention is directed to an apparatus and method for recovering the group III elemental component of a group III-V material waste material. The method includes heating, under a reduced pressure, solid waste materials which contain group III-V material to cause the group III-V material to separate into a group III element and a group V element vapor; drawing off the group V element vapor; condensing the group V element vapor to produce a condensed group V element solid; and zone refining the group III element to produce a purified group III element. The apparatus is designed to carry out this method in the plant which manufactures the group III-V waste material.

Abstract: A process for refining high-impurity blister copper to anode quality copper is disclosed. In an oxidation step of a blister copper refining stage, soda ash fluxing removes antimony and arsenic while also removing sulfur and iron. In a deoxidation step of the blister copper refining stage, sulfur hexafluoride is injected at a controlled oxygen concentration to remove bismuth while reducing the oxygen content. Slag is continuously or periodically skimmed from the surface of the molten blister copper to prevent re-entry of impurities. The process may be carried out in batch operation or, in a preferred embodiment, in continuous flow-through operation.

Abstract: The present invention relates to a process for the production of metal alloys, metal oxides and slag-based products, such as mineral wool, from industrial waste materials. More specifically, the present invention relates to a process for recycling industrial waste materials into valuable commercial products, including, pure metals, metal alloys, metal oxides, and a molten slag comprising non-reducible metal oxides which thereafter can be converted to vitreous fiber and shot. Industrial waste materials suitable for use in the present invention include metal-containing waste products, particularly inorganic hazardous waste materials. The present process accomplishes total recycling in such a manner that the entire industrial waste material is consumed and converted to useful products.

Abstract: Fire-refined blister copper is produced from copper concentrate by a process comprising:A. melting and oxidizing the copper concentrate in a smelting furnace to produce molten matte and slag, and to separate one from the other;B. removing the molten matte from the smelting furnace;C. solidifying the molten matte;D. injecting the solidified matte into a converting furnace in which the matte is converted to blister copper and slag; andE. transferring the blister copper from the converting furnace to an anode furnace to produce fire-refined blister copper.After the fire-refined blister copper is produced in the anode furnace, it is typically transferred to an anode casting wheel on which it is converted to copper anodes suitable for subsequent electrolytic refining to cathode copper.

Abstract: A smelting process for blending hazardous and non-hazardous inorganic industrial wastes with carbon or aluminum reducing agents to simultaneously recover metal alloys (reducible metals), metal oxides (volatile reducible metals), carbon dioxide and man-made vitreous fiber (non reducible metals). Wastes including hazardous wastes of U.S. EPA Series D, F, P, K, and U are pulverized and blended with liquids such as water or waste water to produce a homogeneous mass. The mass is formed into briquettes and melted in a cupola or plasma arc furnace in the presence of carbon or aluminum to reduce metals. Other types of furnaces such as an electric arc furnace may be used to avoid the steps of forming and curing briquettes. Reduction is carried out at temperatures between 1660 and 3100 degrees Fahrenheit. Calcium flux from calcium-stabilized wastes enhances mineral wool quality, lowers the sulfur content of metals and raises pH to facilitate metal reduction. Reducible metals are reduced and drawn off into molds.

Abstract: A process and an apparatus for purifying waste gases from a secondary aluminum melting plant are provided, by which the individual waste gas flows are collected and thermally post-combusted, wherein the generation of the energy necessary for post-combustion is provided by waste substances of high caloric value.

Abstract: This invention provides a process for the recovery of titanium values from a complex matrix comprising titanium nitride. The process comprises chlorinating the titanium nitride in the matrix to obtain a reaction product containing titanium chloride, and separating the titanium chloride from the reaction product. The invention also provides for the production of said complex matrix containing titanium nitride by nitriding titanium values in complex titanium-containing starting materials such as complex metallurgical titaniferous slags and ilmenite, perovskite, armalcolite and fassaite.

Abstract: A method of recycling hazardous and non-hazardous industrial wastes to reclaim valuable metals, metal alloys, and metal oxides, and to produce mineral wool. Wastes including hazardous wastes of USEPA Series D, F, P, K, and U are pulverized and blended with liquids such as water or wastewater to produce a homogeneous mass. Calcium from calcium-stabilized wastes is used to enhance the quality of the mineral wool, lower the sulfur content, remove phosphorous, and raise pH to facilitate metal reduction. The mass is formed into briquettes and melted in a cupola or shaft furnace in the presence of carbon or aluminum to reduce metals. Other types of furnaces such as an electric arc furnace may be used to avoid the steps of forming and curing briquettes. Reduction is carried out at temperatures between 1660 and 3100 degrees Fahrenheit. Reducible metals are reduced and drawn off into molds. Substantial purity is obtained in the recovered reducible metals.

Abstract: Spent oxidic catalyst, such as vanadium pentoxide from a sulphuric acid manfacturing process, is rendered into an environmentally acceptable non-leachable form suitable for disposable by incorporation into a vitrified amorphous slag formed of oxidic slag forming agents such as CaO, SiO.sub.2, FeO and Al.sub.2 O.sub.3. The vitrified slag may be formed as part of a conventional ferrous or non-ferrous smelting process, or may employ a pre-existing slag from such a process.

Abstract: The present invention relates to a process and a plant for the processing of saline slag from the melting of aluminium scrap and waste with a saline flux in which the salts constituting the flux are recovered and other components of the slag are separated. The harmful or toxic gases developed during this processing are subjected to combustion to produce flue gases dispersible in the atmosphere with recovery of combustion heat, preferably used over in processing the slag.

Abstract: Fire-refined blister copper is produced from copper concentrate by a process comprising:A. melting and oxidizing the copper concentrate in a smelting furnace to produce molten matte and slag, and to separate one from the other;B. removing the molten matte from the smelting furnace;C. solidifying the molten matte;D. injecting the solidified matte into a converting furnace in which the matte is converted to blister copper and slag; andE. transfering the blister copper from the converting furnace to an anode furnace to produce fire-refined blister copper.After the fire-refined blister copper is produced in the anode furnace, it is typically transferred to an anode casting wheel on which it is converted to copper anodes suitable for subsequent electrolytic refining to cathode copper.