Abstract: Utilization of process and equipment for oxidation of metal sulfides, preferably two step metal sulfide oxidation reactions, and more preferably with looping back of second step oxide to the first step as an oxidizing agent, to generate sulfur dioxide and a useful metal or metal oxide, and react the sulfur dioxide with halogen (iodine or bromine) and water to produce sulfuric and halogen acid under moderate process conditions and equipment requirements and then dissociating the halogen acids (HI or HBr) to halogen and hydrogen as an overall environmentally and cost efficient and otherwise acceptable safe process for producing hydrogen and other useful products.

Abstract: High purity refractory metals, valve metals, refractory metal oxides, valve metal oxides, or alloys thereof suitable for a variety of electrical, optical and mill product/fabricated parts usages are produced from their respective oxides by metalothermic reduction of a solid or liquid form of such oxide using a reducing agent that establishes (after ignition) a highly exothermic reaction, the reaction preferably taking place in a continuously or step-wise moving oxide such as gravity fall with metal retrievable at the bottom and an oxide of the reducing agent being removable as a gas or in other convenient form and unreacted reducing agent derivatives being removable by leaching or like process.

Abstract: A method of preparing primary refractory metals (e.g., primary tantalum metal) by contacting a particulate refractory metal oxide (e.g., tantalum pentoxide) with a heated gas (e.g., a plasma), is described. The heated gas comprises hydrogen gas. The temperature range of the heated gas and the mass ratio of hydrogen gas to refractory metal oxide are each selected such that: (i) the heated gas comprises atomic hydrogen; (ii) the refractory metal oxide feed material is substantially thermodynamically stabilized (i.e., the concurrent formation of suboxides that are not reduced by atomic hydrogen is minimized); and (iii) the refractory metal oxide is reduced by contact with the heated gas, thereby forming primary refractory metal (e.g., primary tantalum metal and/or primary niobium metal).

Abstract: A method of producing a refractory metal powder that includes providing a metal powder containing magnesium tantalate or magnesium niobate; and heating the powder in an inert atmosphere in the presence of magnesium, calcium and/or aluminum to a temperature sufficient to remove magnesium tantalate or magnesium niobate from the powder and/or heating the powder under vacuum to a temperature sufficient to remove magnesium tantalate or magnesium niobate from the powder, the heating steps being performed in any order. The metal powder can be formed into pellets at an appropriate sintering temperature, which can be formed into electrolytic capacitors.

Abstract: A method of producing a refractory metal powder by (A) combining (i) an oxide particle component and (ii) a reducing agent; (B) forming a substantially uniform mixture of (i) and (ii); (C) continuously feeding the mixture into a furnace; (D) igniting the mixture at a reaction zone and starting a reaction that is sufficiently exothermic to form a high temperature flash; (E) starting a reaction that is sufficiently exothermic to form a high temperature self-sustaining flash; and (F) producing a free-flowing reduced oxide powder.