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The recycling of Nb-Ti superconductor scraps as metal composite material and Ta capacitor scraps as metal-oxygen composite material is proposed in order to build a new process for mass production of rare metals from scraps as urban minerals., The recycling of Nb-Ti superconductor scraps as metal composite material and Ta capacitor scraps as metal-oxygen composite material is proposed in order to build a new process for mass production of rare metals from scraps as urban minerals.

Electric-precipitator dust has been analysed by various methods including x-ray diffraction, infra-red, mass, TGA and DTA. From these analyses the major components were found to be compounds of Zn, Ca, Mg, Al, Pb, Fe, Si, Cu and Ti. The origin of these compounds is discussed. Possible processes for the treatment of E.P. dust are proposed, suggesting the utilisation of the dust as Na and K resources., Electric-precipitator dust has been analysed by various methods including x-ray diffraction, infra-red, mass, TGA and DTA. From these analyses the major components were found to be compounds of Zn, Ca, Mg, Al, Pb, Fe, Si, Cu and Ti. The origin of these compounds is discussed. Possible processes for the treatment of E.P. dust are proposed, suggesting the utilisation of the dust as Na and K resources.

The ferroniobium chlorides obtained were shown the be iron III chloride and niobium pentachloride. Preliminary separation of niobium pentachloride from iron III chloride is possible by selective condensation with temperature gradient techniques. Selective reduction of iron III chloride to iron II chloride by iron powder was conducted to separate niobium pentachloride from iron II chloride by volatility difference., The ferroniobium chlorides obtained were shown the be iron III chloride and niobium pentachloride. Preliminary separation of niobium pentachloride from iron III chloride is possible by selective condensation with temperature gradient techniques. Selective reduction of iron III chloride to iron II chloride by iron powder was conducted to separate niobium pentachloride from iron II chloride by volatility difference.

Studies of the extraction of zirconium from caldasite through a chloride process are described. The process consists of chlorination of the ore and selective condensation of volatile chlorides containing zirconium. A process flowsheet for the chlorination of caldasite to extract zirconium has also been proposed., Studies of the extraction of zirconium from caldasite through a chloride process are described. The process consists of chlorination of the ore and selective condensation of volatile chlorides containing zirconium. A process flowsheet for the chlorination of caldasite to extract zirconium has also been proposed.

The direct thermal decomposition of molybdenite concentrate (MoS2 = 92.3 mass %, SiO2 = 3.2 mass %, Fe = 0.65 mass %) in a molten state under Ar plasma-arc heating produces a molybdenum metal product. The product can then be refined to pure molybdenum metal by H2-Ar plasma-arc melting. Sulphur is removed as small bubbles from the melt under Ar plasma-arc heating. Silicon is separated as a slag and eliminated as a SiO-vapour from the melt. During H2-Ar plasma-arc melting of the thermally decomposed molybdenum products non-metallic and iron impurities are removed. These excellent refining processes are believed to be caused by dissociated and activated hydrogen atoms in a H2-Ar arc plasma., The direct thermal decomposition of molybdenite concentrate (MoS2 = 92.3 mass %, SiO2 = 3.2 mass %, Fe = 0.65 mass %) in a molten state under Ar plasma-arc heating produces a molybdenum metal product. The product can then be refined to pure molybdenum metal by H2-Ar plasma-arc melting. Sulphur is removed as small bubbles from the melt under Ar plasma-arc heating. Silicon is separated as a slag and eliminated as a SiO-vapour from the melt. During H2-Ar plasma-arc melting of the thermally decomposed molybdenum products non-metallic and iron impurities are removed. These excellent refining processes are believed to be caused by dissociated and activated hydrogen atoms in a H2-Ar arc plasma.

The composition of the tantalum capacitor scraps is identical to the Ta-Ta2O5-MnO2 ternary mixture. The Ta content is above 90%. Manganese was removed rapidly with vaporisation of manganese from the melt by Ar, H2-Ar plasma melting and reduced to under 20 mass ppm. Deoxidation reduced the oxygen content to under 100 mass ppm. Other minor impurities such as N, Fe and Ni were eliminated as much as possible by hydrogen plasma melting., The composition of the tantalum capacitor scraps is identical to the Ta-Ta2O5-MnO2 ternary mixture. The Ta content is above 90%. Manganese was removed rapidly with vaporisation of manganese from the melt by Ar, H2-Ar plasma melting and reduced to under 20 mass ppm. Deoxidation reduced the oxygen content to under 100 mass ppm. Other minor impurities such as N, Fe and Ni were eliminated as much as possible by hydrogen plasma melting.

Fundamental data for the recycling of rare earth magnet scraps (the solubilities of Sm2(SO4)3 in H2SO4.H2O and CoSO4.H2O as well as the solubilities of Nd2(SO4)3 in H2SO4.H2O and FeSO4.H2O) were determined in the temperature range 0 to 80 degrees C., Fundamental data for the recycling of rare earth magnet scraps (the solubilities of Sm2(SO4)3 in H2SO4.H2O and CoSO4.H2O as well as the solubilities of Nd2(SO4)3 in H2SO4.H2O and FeSO4.H2O) were determined in the temperature range 0 to 80 degrees C.

The deposit was found to contain ankerite, calcite, dolomite, synchisite and barite. The ore can be easily dissolved in concentrated HCl solution, and selective leaching by controlling pH and reaction time and selective precipitation by adding sodium hydroxide and ammonium oxalate are possible., The deposit was found to contain ankerite, calcite, dolomite, synchisite and barite. The ore can be easily dissolved in concentrated HCl solution, and selective leaching by controlling pH and reaction time and selective precipitation by adding sodium hydroxide and ammonium oxalate are possible.

A review of the titanium metal industry, giving data on prices, production, capacity, applications, energy consumption, costs, pollution control and scrap recovery and recycling., A review of the titanium metal industry, giving data on prices, production, capacity, applications, energy consumption, costs, pollution control and scrap recovery and recycling.

The Kawamata pegmatite was found to contain a range of rare earth minerals, including yttrogummite, yttrialite, xenotime, abukumalite, uraninite, orthite and fergusonite. Alpha radiation from the uranium and thorium content appeared to have resulted in metamictisation of the pegmatite. The possibility of exploiting the pegmatite as a source of rare earth elements is discussed., The Kawamata pegmatite was found to contain a range of rare earth minerals, including yttrogummite, yttrialite, xenotime, abukumalite, uraninite, orthite and fergusonite. Alpha radiation from the uranium and thorium content appeared to have resulted in metamictisation of the pegmatite. The possibility of exploiting the pegmatite as a source of rare earth elements is discussed.

High-purity selenium was separated in three stages. Firstly, there was selective separation of selenium as selenium dioxide by oxidising roasting at high temperature, 600 degrees C. Secondly, there was selective leaching of selenium dioxide from a selenium dioxide and tellurium dioxide mixture, and reduction of selenium dioxide by SO2 gas at a solution temperature of 80 degrees C. Finally, there was selective distillation of selenium at low pressure., High-purity selenium was separated in three stages. Firstly, there was selective separation of selenium as selenium dioxide by oxidising roasting at high temperature, 600 degrees C. Secondly, there was selective leaching of selenium dioxide from a selenium dioxide and tellurium dioxide mixture, and reduction of selenium dioxide by SO2 gas at a solution temperature of 80 degrees C. Finally, there was selective distillation of selenium at low pressure.

The zirconium ore was formed as a mixture of baddeleyite and zircon which was identified as caldasite from the microscopic, X-ray and electron microprobe studies. The ore contained a high content of uranium and thorium oxides, probably sufficient for nuclear fuel resources. Caldasite was then evaluated from a metallurgical viewpoint. The techniques used were chlorination, selective condensation, fractional distillation and then reduction, hydrolysis or C.V.D., The zirconium ore was formed as a mixture of baddeleyite and zircon which was identified as caldasite from the microscopic, X-ray and electron microprobe studies. The ore contained a high content of uranium and thorium oxides, probably sufficient for nuclear fuel resources. Caldasite was then evaluated from a metallurgical viewpoint. The techniques used were chlorination, selective condensation, fractional distillation and then reduction, hydrolysis or C.V.D.

The production and reserves of rutile and ilmenite are given. The Kroll and Hunter processes are described., The production and reserves of rutile and ilmenite are given. The Kroll and Hunter processes are described.

Ductile high purity niobium, with 20 ppm carbon and 70 ppm oxygen was produced. Metal impurities, such as Fe, Al, Si, which are more volatile than niobium were removed effectively to the levels of a few parts per million with electron beam melting., Ductile high purity niobium, with 20 ppm carbon and 70 ppm oxygen was produced. Metal impurities, such as Fe, Al, Si, which are more volatile than niobium were removed effectively to the levels of a few parts per million with electron beam melting.

Measurement of the melting temperatures and specific electrical conductances of the AlCl3-MgCl2 melts have been undertaken to study the influence of MgCl2 as a salt additive. It was found that the addition of MgCl2 only lowers the temperature of the bath and does not form any compound that may precipitate during electrolysis. Chlorine gas dissolved in the melt containing MgCl2 is found to be less reactive., Measurement of the melting temperatures and specific electrical conductances of the AlCl3-MgCl2 melts have been undertaken to study the influence of MgCl2 as a salt additive. It was found that the addition of MgCl2 only lowers the temperature of the bath and does not form any compound that may precipitate during electrolysis. Chlorine gas dissolved in the melt containing MgCl2 is found to be less reactive.