In the natural world, thorium often coexists with zirconium, and zirconium-containing minerals contain lanthanum, lanthanum and zirconium are isomorphous, and lanthanum is mainly contained in zircon. Industrially used zircon contains 0.5-2% HfO2. HfO2 in hafnium zircon in secondary zircon ores can be up to 15%. There is also a metamorphic zirconium, which contains more than 5% HfO2. The latter two minerals have low reserves and have not been used in industry. Germanium is mainly recovered from the production of zirconium.
The smelting of niobium is basically the same as that of zirconium and is generally divided into five steps. The first step is the decomposition of ore, there are three methods: 1 Zircon chloride obtained (Zr, Hf) Cl4. 2 The alkaline fusion of zircon, zircon and NaOH melt at about 600 °C, more than 90% of (Zr, Hf) O2 into Na2 (Zr, Hf) O3, which SiO2 into Na2SiO3, removed with water. Na2(Zr,Hf)O3 can be used as a raw solution for the separation of zirconium and hafnium after it is dissolved in HNO3. However, due to the presence of SiO2 colloids, it is difficult to extract and separate the solvent. 3 Sintered with K2SiF6. After immersing in water, K2(Zr,Hf)F6 solution was obtained. The solution can separate zirconium yttrium by fractional crystallization. The second step is the separation of zirconium and hafnium. The solvent extraction separation method can be used with the hydrochloric acid-MIBK (methyl isobutyl ketone) system and the HNO3-TBP (tributyl phosphate) system. The use of high-pressure (above 20 atm) HfCl4 and ZrCl4 melt vapor pressure difference for multi-stage fractionation technology has long been research, can eliminate the need for secondary chlorination process, reduce costs. However, due to the corrosion problems of (Zr,Hf)Cl4 and HCl, it is not easy to find a suitable material of the fractionation column, and the quality of ZrCl4 and HfCl4 will be reduced, which will increase the purification cost. The third step is secondary chlorination of HfO2 to produce crude HfCl4 for reduction. The fourth step is the purification and magnesium reduction of HfCl4. This process is the same as the purification and reduction of ZrCl4, and the semi-finished product obtained is a crude sponge. The fifth step is vacuum distillation of the crude sponge mash to remove MgCl2 and recover excess metal magnesium. The finished product is a sponge metal ray. If the reducing agent uses sodium instead of magnesium, the fifth step is changed to flooding.
Sponges must be carefully removed from the sputum to avoid spontaneous combustion. The large sponges are broken into small pieces of a certain size so as to be pressed into consumable electrodes and then cast into ingots. It should also prevent spontaneous combustion when broken. The further purification of sponge gills is the same as that of titanium and zirconium, using iodide thermal decomposition. The control conditions are slightly different from those of zirconium, in which small pieces of sponges around the iodization tank are kept at a temperature of 600° C., while the central hot wire temperature is 1600° C., which is higher than the 1300° C. when making the “crystal rods†of zirconium. . The forming process of the crucible includes the steps of forging, extruding, pulling the tube, and the like, as well as the method of processing zirconium.
The main purpose of helium is to make control rods for nuclear reactors. Pure niobium has plasticity, easy processing, high temperature resistance and corrosion resistance, and is an important material for the atomic energy industry. The thermal neutron capture of neon is large and it is an ideal neutron absorber. It can be used as a control rod and protection device for nuclear reactors. Powder can be used as rocket propeller. X-ray tube cathodes can be manufactured in the electrical industry. The niobium alloy can be used as a front protective layer for rocket nozzles and gliding re-entry vehicles. The Hf-Ta alloy can be used to make tool steel and resistance materials. In heat-resistant alloys, niobium is used as an additive element, such as tungsten, molybdenum, niobium, and other alloys. Due to its high hardness and melting point, HfC can be used as an additive for hard alloys. 4TaC•HfC has a melting point of about 4215°C and is the highest known melting point compound.
The smelting of niobium is basically the same as that of zirconium and is generally divided into five steps. The first step is the decomposition of ore, there are three methods: 1 Zircon chloride obtained (Zr, Hf) Cl4. 2 The alkaline fusion of zircon, zircon and NaOH melt at about 600 °C, more than 90% of (Zr, Hf) O2 into Na2 (Zr, Hf) O3, which SiO2 into Na2SiO3, removed with water. Na2(Zr,Hf)O3 can be used as a raw solution for the separation of zirconium and hafnium after it is dissolved in HNO3. However, due to the presence of SiO2 colloids, it is difficult to extract and separate the solvent. 3 Sintered with K2SiF6. After immersing in water, K2(Zr,Hf)F6 solution was obtained. The solution can separate zirconium yttrium by fractional crystallization. The second step is the separation of zirconium and hafnium. The solvent extraction separation method can be used with the hydrochloric acid-MIBK (methyl isobutyl ketone) system and the HNO3-TBP (tributyl phosphate) system. The use of high-pressure (above 20 atm) HfCl4 and ZrCl4 melt vapor pressure difference for multi-stage fractionation technology has long been research, can eliminate the need for secondary chlorination process, reduce costs. However, due to the corrosion problems of (Zr,Hf)Cl4 and HCl, it is not easy to find a suitable material of the fractionation column, and the quality of ZrCl4 and HfCl4 will be reduced, which will increase the purification cost. The third step is secondary chlorination of HfO2 to produce crude HfCl4 for reduction. The fourth step is the purification and magnesium reduction of HfCl4. This process is the same as the purification and reduction of ZrCl4, and the semi-finished product obtained is a crude sponge. The fifth step is vacuum distillation of the crude sponge mash to remove MgCl2 and recover excess metal magnesium. The finished product is a sponge metal ray. If the reducing agent uses sodium instead of magnesium, the fifth step is changed to flooding.
Sponges must be carefully removed from the sputum to avoid spontaneous combustion. The large sponges are broken into small pieces of a certain size so as to be pressed into consumable electrodes and then cast into ingots. It should also prevent spontaneous combustion when broken. The further purification of sponge gills is the same as that of titanium and zirconium, using iodide thermal decomposition. The control conditions are slightly different from those of zirconium, in which small pieces of sponges around the iodization tank are kept at a temperature of 600° C., while the central hot wire temperature is 1600° C., which is higher than the 1300° C. when making the “crystal rods†of zirconium. . The forming process of the crucible includes the steps of forging, extruding, pulling the tube, and the like, as well as the method of processing zirconium.
The main purpose of helium is to make control rods for nuclear reactors. Pure niobium has plasticity, easy processing, high temperature resistance and corrosion resistance, and is an important material for the atomic energy industry. The thermal neutron capture of neon is large and it is an ideal neutron absorber. It can be used as a control rod and protection device for nuclear reactors. Powder can be used as rocket propeller. X-ray tube cathodes can be manufactured in the electrical industry. The niobium alloy can be used as a front protective layer for rocket nozzles and gliding re-entry vehicles. The Hf-Ta alloy can be used to make tool steel and resistance materials. In heat-resistant alloys, niobium is used as an additive element, such as tungsten, molybdenum, niobium, and other alloys. Due to its high hardness and melting point, HfC can be used as an additive for hard alloys. 4TaC•HfC has a melting point of about 4215°C and is the highest known melting point compound.