EP0299791B1 - Procédé et installation pour la production du titane - Google Patents
Procédé et installation pour la production du titane Download PDFInfo
- Publication number
- EP0299791B1 EP0299791B1 EP88306510A EP88306510A EP0299791B1 EP 0299791 B1 EP0299791 B1 EP 0299791B1 EP 88306510 A EP88306510 A EP 88306510A EP 88306510 A EP88306510 A EP 88306510A EP 0299791 B1 EP0299791 B1 EP 0299791B1
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- EP
- European Patent Office
- Prior art keywords
- titanium
- reaction vessel
- product
- reaction
- reducing metal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 title claims description 147
- 239000010936 titanium Substances 0.000 title claims description 146
- 229910052719 titanium Inorganic materials 0.000 title claims description 146
- 238000004519 manufacturing process Methods 0.000 title claims description 13
- 238000006243 chemical reaction Methods 0.000 claims description 220
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical group [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 65
- 239000011777 magnesium Substances 0.000 claims description 65
- 229910052749 magnesium Inorganic materials 0.000 claims description 65
- 229910052751 metal Inorganic materials 0.000 claims description 65
- 239000002184 metal Substances 0.000 claims description 64
- 239000003795 chemical substances by application Substances 0.000 claims description 54
- 239000000047 product Substances 0.000 claims description 53
- XJDNKRIXUMDJCW-UHFFFAOYSA-J titanium tetrachloride Chemical compound Cl[Ti](Cl)(Cl)Cl XJDNKRIXUMDJCW-UHFFFAOYSA-J 0.000 claims description 45
- 239000007788 liquid Substances 0.000 claims description 33
- 239000006227 byproduct Substances 0.000 claims description 28
- 238000000034 method Methods 0.000 claims description 28
- 238000002844 melting Methods 0.000 claims description 24
- 230000008018 melting Effects 0.000 claims description 24
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 20
- 238000001816 cooling Methods 0.000 claims description 12
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 2
- 238000004581 coalescence Methods 0.000 claims description 2
- 229910052708 sodium Inorganic materials 0.000 claims description 2
- 239000011734 sodium Substances 0.000 claims description 2
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 description 84
- 229910001629 magnesium chloride Inorganic materials 0.000 description 42
- 238000010438 heat treatment Methods 0.000 description 35
- 230000005674 electromagnetic induction Effects 0.000 description 15
- 238000006722 reduction reaction Methods 0.000 description 15
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 14
- 229910052786 argon Inorganic materials 0.000 description 7
- 238000009835 boiling Methods 0.000 description 7
- 239000002826 coolant Substances 0.000 description 7
- 239000007789 gas Substances 0.000 description 6
- 239000012298 atmosphere Substances 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 4
- 238000007599 discharging Methods 0.000 description 4
- 239000000376 reactant Substances 0.000 description 4
- 238000000926 separation method Methods 0.000 description 4
- 239000007795 chemical reaction product Substances 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000006698 induction Effects 0.000 description 3
- 238000007789 sealing Methods 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 229910010293 ceramic material Inorganic materials 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 239000012777 electrically insulating material Substances 0.000 description 2
- 238000010574 gas phase reaction Methods 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 239000003779 heat-resistant material Substances 0.000 description 2
- 229910001507 metal halide Inorganic materials 0.000 description 2
- 150000005309 metal halides Chemical class 0.000 description 2
- 239000012768 molten material Substances 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- -1 alumina Chemical compound 0.000 description 1
- 239000012300 argon atmosphere Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 229910052735 hafnium Inorganic materials 0.000 description 1
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 238000002386 leaching Methods 0.000 description 1
- 229910001338 liquidmetal Inorganic materials 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- 239000010955 niobium Substances 0.000 description 1
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- ZWYDDDAMNQQZHD-UHFFFAOYSA-L titanium(ii) chloride Chemical compound [Cl-].[Cl-].[Ti+2] ZWYDDDAMNQQZHD-UHFFFAOYSA-L 0.000 description 1
- YONPGGFAJWQGJC-UHFFFAOYSA-K titanium(iii) chloride Chemical compound Cl[Ti](Cl)Cl YONPGGFAJWQGJC-UHFFFAOYSA-K 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B34/00—Obtaining refractory metals
- C22B34/10—Obtaining titanium, zirconium or hafnium
- C22B34/12—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08
- C22B34/1263—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining metallic titanium from titanium compounds, e.g. by reduction
- C22B34/1268—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining metallic titanium from titanium compounds, e.g. by reduction using alkali or alkaline-earth metals or amalgams
- C22B34/1272—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining metallic titanium from titanium compounds, e.g. by reduction using alkali or alkaline-earth metals or amalgams reduction of titanium halides, e.g. Kroll process
Definitions
- This invention relates to a method for producing metallic titanium and an apparatus therefor, and more particularly to a method and apparatus for producing metallic titanium from titanium tetrachloride at a reaction temperature above the melting point of titanium.
- the reduction reaction is generally carried out at a temperature below the melting point of metallic titanium while keeping the reduction vessel at normal or reduced pressure to produce spongy metallic titanium.
- the spongy metallic titanium product is subjected to vacuum separation or leaching to remove any excess metallic magnesium and magnesium chloride (by-product) remaining in the fine internal voids of the metallic titanium product and is thus purified.
- the purified metallic titanium is then crushed and formed into a shape suitable for melting. After melting, an ingot of titanium is formed.
- the Kroll method is a batch type process. Accordingly, producing the metallic titanium ingot according to the Kroll method requires at least four discontinuous or independent steps comprising a reduction reaction step, a vacuum separation step, a crushing step and a melting step.
- the Kroll method also has the following disadvantages.
- the spongy metallic titanium which is the reaction product is firmly adhered to a reduction reaction vessel, so that much labour and time are required for peeling the adhered reaction product from the vessel.
- Another disadvantage is that it is very difficult to remove the heat of reaction from the reaction system during the reduction step sufficiently rapidly.
- a further disadvantage is that the titanium is produced at a sufficiently elevated temperature to increase its activity. Accordingly, it is readily polluted with the material of the reaction vessel wall.
- Still another disadvantage is that the separation step for purification of the titanium requires much attention in order to prevent contamination of the titanium with moisture, air and the like. Accordingly, removal of the unreacted material and the by-product must be carried out in a vacuum or argon atmosphere.
- Japanese Patent Application Laying-Open Publication No.35733/1981 discloses a method for producing metallic titanium which comprises the steps of introducing titanium chloride and a reducing metal agent both in the vapour state into a reaction vessel to react both under conditions so that a liquid metallic titanium product is obtained together with the chloride of the reducing metal agent in the form of a vapour.
- the chloride by-product of the reducing metal agent is separated from the titanium product for recovery and the metallic titanium product is solidified in a mould kept at a temperature below the melting point of the metallic titanium product to obtain an ingot which is removed from the reaction vessel.
- Japanese Patent Publication No.19761/1971 discloses a method for producing metal comprising the steps of introducing titanium tetrachloride vapour and a liquid reducing metal agent into liquid metal in a reaction vessel, heating a reaction zone to a temperature above the melting point of titanium to obtain a metallic titanium product and a chloride by-product of the reducing metal agent in a molten state under a vapour pressure of the reducing metal agent at the relevant temperature, separating the product and by-product from each other using the difference in their gravities, and separately removing them from the reaction vessel.
- the method taught in Japanese Patent Publication No.19761/1971 is to reduce titanium tetrachloride with magnesium to produce metallic titanium while keeping the temperature in the reaction zone at about 1730°C and the pressure in the reaction vessel at about 5 atms corresponding to a partial pressure of the magnesium chloride by-product at that temperature to produce the metallic titanium product and the magnesium chloride by-product in a molten state.
- the reaction zone temperature is about 1720°C and its pressure is about 5 atms which is substantially equal to the vapour pressure of the magnesium chloride, produced in liquid form.
- This results in the magnesium boiling which leads to a failure to maintain the magnesium in an amount sufficient to reduce titanium tetrachloride in the reaction zone fully. This causes the reaction to take place in the presence of insufficient magnesium which often produces lower chlorides of titanium such as titanium trichloride, titanium dichloride and the like.
- the reactants (titanium tetrachloride in the form of a gas and magnesium in the form of a liquid) are supplied through graphite pipes to a molten layer of the reaction product the bottom of the reaction vessel to carry out the reaction in the molten layer.
- This causes the open end of the graphite pipes to be corroded by the active molten titanium product.
- the molten titanium product contacts each of the reactants at a relatively low temperature at the open end of the pipes, solidifying the reactants, and so clogging the pipes.
- the reaction is a reduction reaction taking place in the molten layer of titanium, the titanium product is contaminated with unreacted reactants, the by-product and the like.
- the lack of magnesium in the reaction zone leads to a decrease in reaction efficiency per a reaction sectional area.
- a method for producing titanium by reduction of titanium tetrachloride with a reducing metal agent which comprises the steps of: maintaining the temperature in a reaction zone in a reaction vessel above the melting point of a metallic titanium to be produced; supplying titanium tetrachloride and the reducing metal agent to the reaction vessel to react to produce a metallic titanium product and a chloride by-product of the reducing metal agent while maintaining the product and the by-product in a molten state; separating the metallic titanium product and the chloride by-product of the reducing metal agent from each by making use of the differences in their densities; collecting the metallic titanium product at the bottom of the reaction vessel; and continuously drawing off the metallic titanium product from the bottom of the reaction vessel; characterised in that the pressure in the reaction zone is maintained above the vapour pressure of the reducing metal agent at the temperature in the reaction zone.
- the titanium product is solidified by cooling as it is withdrawn.
- a molten bath of chloride of the reducing metal agent and optionally also of the reducing metal agent itself is previously formed in the reaction vessel so that the surface of the molten bath constitutes the reaction zone and titanium tetrachloride and the reducing metal agent are supplied to the reaction zone.
- titanium tetrachloride is supplied in liquid form from the top of the reaction vessel and the reducing metal agent is supplied either in the same way or is injected into the bath.
- the chloride by-product of the reducing metal agent is discharged from the reaction vessel at a rate arranged to maintain the position of the reaction zone substantially constant.
- the method may also include the steps of inserting a titanium ingot into the bottom of the reaction vessel resulting in the coalescence of the separated metallic titanium metal product with the titanium ingot and drawing the metallic titanium product out continuously together with the titanium ingot at a rate corresponding to the amount of the metallic titanium product being coalesced with the titanium ingot.
- a suitable apparatus for producing metallic titanium by the reduction of titanium tetrachloride with a reducing metal agent in accordance with the invention comprises a reaction vessel having a reaction zone in which a temperature above the melting point of the titanium product is defined and which is kept at a pressure sufficient to prevent boiling of the reducing metal agent and its chloride at that temperature; a reducing metal agent feed pipe for supplying the reducing metal agent in the form of a liquid from the side or the top of the reaction vessel to the reaction zone; a titanium tetrachloride feed pipe for supplying titanium tetrachloride from the top of the reaction vessel to the reaction zone; a discharge pipe for discharging the chloride by-product of the reducing metal agent from the side of the reaction vessel; heating means arranged outside the reaction vessel at a position corresponding to the reaction zone and a withdrawing section at the bottom of the reaction vessel for continuously drawing out the metallic titanium product characterised in that the reaction vessel comprises a plurality of longitudinal segments separated by slits thereby dividing the reaction vessel in its longitudinal
- One preferred embodiment of the invention includes a reaction vessel made of thick titanium plate in which a reaction zone is defined and which is kept at a pressure sufficient to prevent boiling of the reducing metal agent and its chloride.
- a reducing metal agent feed pipe supplies the reducing metal agent in the form of a liquid from the side or top of the reaction vessel to the reaction zone, and a titanium tetrachloride feed pipe supplies titanium tetrachloride from the top of the reaction vessel to the reaction zone.
- a discharge pipe for discharging a chloride by-product of the reducing metal agent extends from the side of the reaction vessel.
- Heating means are arranged outside the reaction vessel at a position corresponding to the reaction zone for carrying out electromagnetic induction heating, resistance heating or the like, and a mould section is arranged at the bottom of the reaction vessel for solidifying the molten metallic titanium product by cooling and continuously drawing out it from the reaction vessel.
- An alternative reaction vessel structure includes a reaction vessel made of metal such as copper or a ceramic material such as alumina, zirconia or the like in which a reaction zone is defined and which is kept at a pressure sufficient to prevent boiling of the reducing metal agent material and its chloride.
- the reaction vessel has a vertically extending hollow shape and is open at the top and bottom.
- the reaction vessel includes a cooling agent circulating path for cooling the inner surface of the reaction vessel and portions of its outer periphery at a position corresponding to the reaction zone.
- the vessel also includes a removal section with heating means for heating a molten material which carries out electromagnetic induction heating, resistance heating or the like.
- a suitable reaction vessel provided with the heating means may comprise a crucible, as disclosed in U.S. Patent No.3,755,091 which is adapted to melt titanium chips, titanium sponge or the like for preparing a titanium ingot and is used in an evacuated inert atmosphere.
- a crucible may be incorporated in a pressure vessel for use as the reaction vessel in the present invention which includes the reaction zone for reducing titanium tetrachloride and the mould section for solidifying the metallic titanium product by cooling and continuously removing it therefrom.
- the present inventors have conducted the following reaction test in order to evaluate the reaction efficiency for reducing titanium tetrachloride with metallic magnesium according to the present invention.
- a pressure in the reaction vessel was kept at 50 atms.
- the reaction vessel was charged with 845g metallic magnesium, which was heated to 1350°C by electromagnetic induction heating or resistance heating to form a molten magnesium bath in the reaction vessel.
- 1340g liquid titanium tetrachloride was fed to the molten magnesium for 50 seconds at a feed rate of 1608g/min.
- the temperature of the bath reached the melting point of titanium in 15 seconds after the beginning of the addition of titanium tetrachloride, thereby producing liquid titanium.
- the yield of titanium was 99% and the reaction efficiency per unit sectional area of the reaction vessel was 62.7 kmol/hr m2.
- the Kroll method was carried out and was found to give a reaction efficiency per unit sectional area of a reaction vessel of 1.3 kmol/hr m2.
- reaction efficiency of the present invention it may not be strictly fair simply to compare the reaction efficiency of the present invention to the reaction efficiency calculated in this way because reaction conditions such as temperature, a feed rate of feedstocks and the like were set differently.
- reaction conditions such as temperature, a feed rate of feedstocks and the like were set differently.
- the reaction between the titanium tetrachloride and metallic magnesium in the present invention exhibits a reaction efficiency at least 49.6 (62.7/1.263) times that of the above described gas phase reaction and 48.2 (62.7/1.3) times as much as that of the Kroll process.
- the fact that the present invention exhibits such a higher reaction efficiency is believed to be due to the liquid metallic magnesium and liquid titanium tetrachloride being supplied to the reaction zone kept there at a high temperature and a high pressure.
- the temperature of the reaction zone is set above the melting point of titanium.
- the bath in the reaction vessel is kept at a temperature of at least 1670°C and more preferably 1827°C, and at a pressure above 42.6 atms, corresponding to the partial pressure of magnesium and more preferably above 48.6 atms corresponding to the total sum of the partial pressure of magnesium (42.6 atms) and magnesium chloride (5.98 atms) at the temperature of 1827°C.
- the reducing metal agent may be used in a stoichiometric amount. However, in order to carry out the reduction fully, it is desirable to use a predetermined excess of the reducing metal agent in the reaction zone to inhibit the production of lower titanium chlorides.
- titanium tetrachloride and a reducing metal agent are supplied in liquid form to a reaction zone for reaction.
- Magnesium or sodium may be used as the reducing metal agent.
- the apparatus shown in Figure 1 includes a reaction vessel structure A which also serves as a pressure vessel.
- the reaction vessel structure A includes an outer shell or outer wall 1 made of a steel plate, an inner wall made of titanium serving as a reaction vessel 3 and a heat insulating material 2 between the outer shell 1 and the reaction vessel 3.
- An inert gas (e.g. argon) is introduced to the reaction vessel 3 from a pressure adjusting pipe 4 through a valve 5, so that the interior of the reaction vessel 3 is set and kept at a pressure sufficient to prevent substantially any boiling of the magnesium and vessel 3 is set and kept at a pressure sufficient to prevent substantially any boiling of the magnesium and magnesium chloride, even when the temperature in a reaction zone defined in the reaction vessel 3 rises above the melting point of titanium.
- the reaction vessel 3 is kept at a pressure of about 50 atms when the temperature of the bath in the reaction vessel 3 is 1827°C.
- an automatic pressure adjusting valve (not shown) is operated to keep the pressure at the set value automatically.
- Liquid magnesium for use as the reducing metal agent is supplied to the reaction zone through a reducing metal agent feed pipe 6 extending through the side wall of the reaction vessel structure A and into the reaction vessel 3.
- liquid titanium tetrachloride is supplied to the reaction zone through a titanium tetrachloride feed pipe 7 extending through the top of the reaction vessel structure A and into the vessel 3.
- the reaction vessel 3 is provided at an intermediate part of its outer periphery (in a vertical direction) surrounding the reaction zone with a heater or heating means 8 adapted to carry out electromagnetic induction heating, resistance heating or the like to adjust the temperature of the reaction zone in the reaction vessel 3 to a level above 1670°C, corresponding to the melting point of titanium.
- a discharge tube 9 is connected to the reaction vessel 3 adjacent to the heating means 8, for discharging magnesium chloride by-product formed by the reduction reaction.
- a mould section 10 for solidifying the molten metallic titanium product is connected at the bottom of the reaction vessel, for cooling and drawing out the titanium product.
- a titanium ingot 11 is inserted in the mould section 10 to close the bottom of the reaction vessel 3 and then magnesium and magnesium chloride are charged in small amounts into the reaction vessel 3.
- the atmosphere in the reaction vessel 3 is replaced with argon gas and then the heater 8 is operated to melt the magnesium and magnesium chloride, resulting in a molten bath of magnesium and magnesium chloride being formed in the reaction vessel 3.
- the molten magnesium 12 floats above the magnesium chloride due to the difference in their densities, so that it may remain separate from the magnesium chloride.
- Titanium tetrachloride supplied to the surface of the molten magnesium layer of the bath reacts as a liquid with the liquid magnesium to produce titanium 14 and magnesium chloride 13. Alternatively, it may react as a vapour with magnesium vapour vapourised from the molten magnesium phase of the bath or indeed with liquid magnesium.
- the heat of reaction and the effect of the heater 8 cause the temperature of the molten bath in the reaction vessel 3 to rise above the melting point of titanium.
- the reaction vessel 3 is kept at a pressure above the vapour pressure of magnesium at that temperature, so the titanium product 14, the magnesium chloride by-product 13 and the magnesium 12 are all kept in a liquid state.
- the molten bath is vertically separated into three layers, namely magnesium 12, magnesium chloride 13 and titanium 14, in that order, due to the differences in their densities.
- the molten metallic titanium product 14 precipitates and sinks through the molten magnesium layer and the molten magnesium chloride layer to the bottom of the reaction vessel 3 and reaches the top of the titanium ingot 11 to coalesce with it as it is produced.
- the titanium ingot 11 is continuously drawn out at a suitable rate, during which the titanium is solidified by cooling.
- the magnesium chloride by-product 13 is discharged through the discharge pipe 9 connected to the side of the reaction vessel 3 at a discharge rate which is adjusted so that the molten bath in the reaction zone is kept constant in depth.
- the titanium ingot 11 is drawn out at a rate corresponding to the amount of titanium precipitated on the titanium ingot (or the precipitation rate of the titanium) by means of rollers (not shown). Accordingly, the position of the molten titanium product above the titanium ingot 11 is kept substantially constant.
- the apparatus shown in Figures 2 and 3 is constructed in substantially the same manner as that of Figure 1 except for the construction of the reaction vessel 3, the arrangement of the reducing material feed pipe 6 and the construction of the heater or heating means 8.
- the reaction vessel 3 is formed as a vertically extending cylindrical shape, the top and bottom of which are open and is divided into two or more segments 32 by means of vertical slits 31 in the wall of the reaction vessel 3. In the illustrated embodiment, it is divided into twelve segments 32.
- Each of the segments 32 is formed of a material of good thermal conductivity for example, a metal such as copper or the like.
- the slits 31 are filled with an electrically insulating and heat resistant material to insulate the segments 32 from one another electrically.
- the segments 32 are each provided with an internal cooling pipe 33 for supplying a cooling agent through them to cool the wall of the reaction vessel 3 defining the reaction zone therein.
- the cooling pipes 33 are connected to one another and between a cooling agent inlet 34 and a cooling agent outlet 35 to form a path for circulating a cooling agent.
- An upwardly extending duct 15 is connected to the open top end of the reaction vessel, the upper end of which is connected to the exterior through a cylinder section 16 and in which the reducing agent feed pipe 6 is located.
- the titanium tetrachloride feed pipe 7 is positioned within the upper portion of the reaction duct 15.
- liquid magnesium and liquid titanium tetrachloride are supplied through the feed pipes 6 and 7 to the reaction zone.
- the reaction vessel 3 is provided at a bottom thereof with a mould section 19, through which a titanium ingot 11 is inserted into the reaction vessel 3.
- the reaction vessel 3 constituted by the segments 32 has at its upper part on the outer periphery at a position corresponding to the reaction zone in the reaction vessel 3, an upper electromagnetic induction heating coil 8a for raising a temperature of the reaction zone above the melting point of titanium (or 1670°C).
- the vessel 3 On its lower part, the vessel 3 has a lower electromagnetic induction heating coil 8b for melting the top of the titanium ingot 11 and the magnesium chloride adjacent the top to keep the top of the ingot constantly in a molten state during the reaction.
- the heating means 8 comprises the upper and lower electromagnetic induction heating coils 8a and 8b.
- the embodiment of Figures 2 and 3 is so constructed that the reaction vessel 3 is divided into a plurality of the cooled segments 32 and the segments 32 are electrically insulated from one another by the slits 31.
- Such a construction substantially prevents the generation of eddy currents in each segment 32 due to electromagnetic induction heating, thereby permitting the molten materials in the reaction zone of the reaction vessel 3 and the top of the titanium ingot to be subjected to induction heating without heating the segments 32.
- the apparatus includes a discharge pipe 9 for discharging the magnesium chloride by-product which is connected to a substantially central portion of a side of the reaction vessel, in this case between the upper and lower heating coils 8a and 8b.
- the reaction vessel 3 is made of a metal agent in view of economic efficiency and maintenance. However, it may be formed of a ceramic material such as alumina, zirconia or the like. In such a case, it would not be necessary to divide the reaction vessel 3 into segments.
- a titanium ingot 11 is inserted into the mould section 10 to close the bottom of the reaction vessel 3 and then magnesium and magnesium chloride are charged in small amounts into the reaction vessel 3. Then, the atmosphere in the reaction vessel 3 is replaced with argon gas and the lower magnetic induction heating coil 8b is operated to melt the top of the titanium ingot 11 while the upper magnetic induction heating coil 8a is operated to melt the magnesium and magnesium chloride charged into the reaction zone, resulting in a molten bath of magnesium and magnesium chloride being formed in the reaction vessel 3.
- Molten magnesium 12 collects and floats above the magnesium chloride due to the difference in their densities and the magnetic field by electromagnetic induction, so that it remains separate from the magnesium chloride. Part of the molten magnesium chloride flows into the gap between the titanium into 11 and the inner surface of the reaction vessel 3 where it solidifies by cooling, to give pressure sealing and electrical insulation actions.
- magnesium feed pipe 6 may be connected to the side of the reaction vessel 3 as in the apparatus of Figure 1.
- Titanium tetrachloride in the reaction zone or at the surface of the molten magnesium layer of the molten bath reacts in liquid form with the liquid magnesium to produce titanium 14 and magnesium chloride 13. Alternatively, it may react as vapour with magnesium vapour vapourised from the molten magnesium layer or with liquid magnesium.
- the heat of reaction and the effect of the heater 8 cause the temperature of the molten bath in the reaction vessel 3 to rise above the melting point of titanium.
- the reaction vessel 3 is kept at a pressure above a vapour pressure of magnesium at that temperature, so that the titanium product 14, the magnesium chloride by-product 13 and the magnesium 12 are all kept in a liquid state.
- the molten bath is vertically separated into three layers, namely, magnesium 12, magnesium chloride 13 and titanium 14, in that order, due to the differences in their densities.
- the molten metallic titanium product 14 precipitates and sinks through the molten magnesium layer and the molten magnesium chloride layer to the bottom of the reaction vessel 3 and reaches the top of the titanium ingot 11, where it remains in the molten state and is subjected to stirring and mixing by the lower electromagnetic induction heating coil 8b. This results in the molten titanium product 14 being homogeneous.
- the titanium product 14 coalesces with the top of the titanium ingot 11 and the titanium ingot 11 is continuously drawn out at a suitable rate, during which the product is cooled and solidified by the cooling agent circulated in the cooling pipes 33 of the segments 32.
- the magnesium chloride by-product 13 is discharged through the discharge pipe 9 connected to the side of the reaction vessel 3 at a discharge rate which is adjusted so that the molten bath at the reaction zone is kept at a constant level.
- a part of the magnesium chloride flows into the gap between the titanium ingot 11 and the wall of the reaction vessel and solidifies there to form an insulating layer which serves to prevent contact between the ingot 11 and the reaction vessel.
- the insulating layer exhibits heat insulating and pressure sealing actions.
- the insulating layer may be partially broken by mechanical friction when the titanium ingot 11 is downwardly drawn out, however, when this happens, the magnesium chloride rapidly flows from the molten magnesium chloride phase into the broken portion of the insulating layer and solidifies to re-form an insulating layer.
- the molten titanium is heated by the lower electromagnetic induction heating coil 8b and tends to levitate at its central portion. Accordingly, magnesium chloride readily flows into the gap between the wall of the reaction vessel and the titanium ingot 11 to facilitate formation of the additional insulating layer.
- the titanium ingot 11 is drawn out at a rate corresponding to the amount of titanium precipitated on the titanium ingot by precipitation by means of rollers (not shown). Accordingly, the position of the molten titanium product above the titanium ingot 11 is kept substantially constant. A part of heat of reaction in the reaction vessel is removed upwards from the reaction vessel 3 by radiation and convention, however, a large part of the heat is removed outwardly by the cooling agent circulated in the circulation pipes 33 at the segments 32 constituting the reaction vessel 3.
- the present invention is carried out under conditions where the temperature of the reaction zone is kept above the melting point of the metallic titanium product and its pressure is kept at least at the vapour pressure of the reducing metal agent at that temperature, so that boiling of the reducing metal agent and its chloride may be substantially prevented to keep them in a liquid state in the reaction vessel, resulting in the reduction being carried out efficiently.
- the present invention also allows the metallic titanium to be produced in the form of a liquid if preferred.
- the separation of the metallic titanium product and the chloride by-product of the reducing metal agent is simple, as is the recovery of the by-product, and the titanium ingot may be directly removed, enabling the whole production apparatus to be small-sized.
- the present invention permits production of metallic titanium to be continuously carried out, so that the separating, crushing and melting steps required in the conventional Kroll process may be eliminated, leading to a significant decrease in producing costs while providing titanium of the highest quality.
- a reaction vessel having an inner diameter of 20cm was used and a titanium ingot having an inner diameter of 10cm was inserted into the mould section of the reaction vessel to close the bottom. 20kg magnesium chloride and 4.6kg magnesium were charged into the reaction vessel, which was then fully closed.
- the atmosphere in the reaction vessel was replaced with argon, the magnesium chloride and magnesium were heated to 1000°C by electromagnetic induction heating and the reaction vessel was pressurised to about 50atms.
- titanium tetrachloride and liquid magnesium kept at 800°C were supplied to the reaction vessel at feed rates of 4.0l/min (7.0kg/min) and 1.2l/min (1.8kg/min), respectively. This caused a temperature of the bath to rise rapidly to 1827°C, and so the power for the electromagnetic induction heating was decreased to keep the temperature at 1827°C ⁇ 50°C.
- the ingot was drawn out downwardly at an average velocity of 4.9cm/min.
- the operation was continued for 3 hours, resulting in a titanium ingot being manufactured in an amount of 0.3 tonne.
- the magnesium chloride by-product produced during the operation was continuously discharged from the reaction vessel at the appropriate rate to keep the depth of the bath in the reaction vessel constant.
- the titanium ingot so produced was compared to sponge titanium produced by the Kroll process. It was found that the titanium ingot had a high purity and quality as indicated in Table 1, in which the figures are in wt% and the balance is titanium in each case.
- a reaction vessel having an inner diameter of 20cm was used and a titanium ingot having an inner diameter of 19.5cm was inserted into the mould section of the reaction vessel to close the bottom. Then, 20kg magnesium chloride and 4.6 kg magnesium were charged into the reaction vessel, which was then fully closed.
- the atmosphere in the reaction vessel was replaced with argon and the top of the titanium ingot and the reaction vessel were heated by electromagnetic induction heating to heat the magnesium chloride and magnesium in the reaction zone to a temperature of 1000°C.
- Magnesium chloride melted by the heating flowed into the gap between the wall of the reaction vessel and the titanium ingot to form an insulating layer which also exhibited a pressure sealing action.
- the reaction vessel was then pressurised to about 50atms. Immediately after such conditions were attained, titanium tetrachloride and liquid magnesium kept at 800°C were supplied to the reaction vessel at feed rates of 4.0l/min (7.0kg/min) and 1.2l/min (1.8kg/min), respectively. This caused the temperature of the bath to rise rapidly to 1827°C, and so the power for the electromagnetic induction heating was decreased to keep the temperature of 1827°C ⁇ 50°C.
- the ingot was drawn out downwardly at an average velocity of 1.3cm/min.
- the operation was continued for 2 hours, resulting in titanium ingot being manufactured in an amount of 0.2 tonne.
- the magnesium chloride by-product produced during the operation was continuously discharged from the reaction vessel at the appropriate rate to keep the depth of the bath in the reaction vessel constant.
- the titanium ingot so produced was compared to sponge titanium produced by the Kroll process. It was found that the titanium ingot had a high purity and quality similar to that shown in Table 1.
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- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
Claims (8)
- Procédé pour la production de titane, par réduction du tétrachlorure de titane à l'aide d'un agent métallique réducteur, comprenant les étapes de : maintien de la température dans une zone de réaction (12) dans un récipient de réaction (3), à une valeur supérieure au point de fusion du titane métallique (14) à produire, amenée du tétrachlorure de titane et de l'agent métallique réducteur dans le récipient de réaction (3) afin de provoquer une réaction de production d'un produit à base de titane métallique (14) et d'un co-produit à base de chlorure (13) provenant de l'agent métallique réducteur, tout en maintenant le produit et le co-produit à l'état fondu, séparation l'un de l'autre du produit à base de titane métallique (14) et du co-produit à base de chlorure (13) de l'agent métallique réducteur, en utilisant leur différence de densité, récupération du produit à base de titane métallique (14) en partie basse du récipient de réaction (3) et extraction continue du produit métallique (14) en partie basse du récipient de réaction (3), caractérisé en ce que la pression régnant dans la zone de réaction (12) est maintenue à une valeur supérieure à la pression de vapeur de l'agent métallique réducteur, à la température de la zone de réaction (12).
- Procédé selon la revendication 1, caractérisé en ce que le produit à base de titane (14) est solidifié par refroidissement lors de son extraction.
- Procédé selon la revendication 1, caractérisé en ce qu'un bain en fusion (12) de chlorure de l'agent métallique réducteur et, en option également de l'agent métallique réducteur est préalablement formé dans le récipient de réaction, de telle façon que la surface du bain en fusion constitue la zone de réaction et que le tétrachlorure de titane et l'agent métallique réducteur sont amenés à la zone de réaction.
- Procédé selon la revendication 3, caractérisé en ce que le tétrachlorure de titane est amené sous forme liquide depuis le haut du récipient de réaction (3) et l'agent métallique réducteur est soit amené de la même manière, soit injecté dans le bain (12).
- Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que le co-produit à base de chlorure (13) de l'agent métallique réducteur est évacué (9) du récipient de réaction, à un débit réglé de façon à maintenir la position de la zone de réaction (12) pratiquement constante.
- Procédé selon l'une quelconque des revendications précédentes, caractérisé par les étapes d'insertion d'un lingot de titane (11) dans la partie basse du récipient de réaction (3), afin de provoquer la coalescence du produit à base de titane métallique (14) avec le lingot de titane (11) et d'extraction du produit à base de titane métallique (14) en continu, conjointement avec le lingot de titane (11), à un débit correspondant à la quantité de produit à base de titane métallique porté à coalescence avec le lingot de titane.
- Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que l'agent métallique réducteur est du magnésium ou du sodium.
- Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que la pression de réaction est supérieure à la somme totale des pressions de vapeur de l'agent métallique réducteur et de son chlorure, à la température de réaction.
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP17701487A JPS6421021A (en) | 1987-07-17 | 1987-07-17 | Production of metallic titanium |
JP177014/87 | 1987-07-17 | ||
JP62190186A JP2554888B2 (ja) | 1987-07-31 | 1987-07-31 | 金属チタンの製造法 |
JP190186/87 | 1987-07-31 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0299791A1 EP0299791A1 (fr) | 1989-01-18 |
EP0299791B1 true EP0299791B1 (fr) | 1992-10-21 |
Family
ID=26497701
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP88306510A Expired - Lifetime EP0299791B1 (fr) | 1987-07-17 | 1988-07-15 | Procédé et installation pour la production du titane |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0299791B1 (fr) |
AU (1) | AU618541B2 (fr) |
CA (1) | CA1328561C (fr) |
DE (1) | DE3875411T2 (fr) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7753989B2 (en) | 2006-12-22 | 2010-07-13 | Cristal Us, Inc. | Direct passivation of metal powder |
US8821611B2 (en) | 2005-10-06 | 2014-09-02 | Cristal Metals Inc. | Titanium boride |
US9127333B2 (en) | 2007-04-25 | 2015-09-08 | Lance Jacobsen | Liquid injection of VCL4 into superheated TiCL4 for the production of Ti-V alloy powder |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AU686444B2 (en) * | 1994-08-01 | 1998-02-05 | Kroftt-Brakston International, Inc. | Method of making metals and other elements |
US7435282B2 (en) | 1994-08-01 | 2008-10-14 | International Titanium Powder, Llc | Elemental material and alloy |
US7445658B2 (en) | 1994-08-01 | 2008-11-04 | Uchicago Argonne, Llc | Titanium and titanium alloys |
US5958106A (en) * | 1994-08-01 | 1999-09-28 | International Titanium Powder, L.L.C. | Method of making metals and other elements from the halide vapor of the metal |
US20070017319A1 (en) | 2005-07-21 | 2007-01-25 | International Titanium Powder, Llc. | Titanium alloy |
LV13528B (en) * | 2006-09-25 | 2007-03-20 | Ervins Blumbergs | Method and apparatus for continuous producing of metallic tifanium and titanium-bases alloys |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2816828A (en) * | 1956-06-20 | 1957-12-17 | Nat Res Corp | Method of producing refractory metals |
US3847596A (en) * | 1968-02-28 | 1974-11-12 | Halomet Ag | Process of obtaining metals from metal halides |
US3775091A (en) * | 1969-02-27 | 1973-11-27 | Interior | Induction melting of metals in cold, self-lined crucibles |
LU81469A1 (fr) * | 1979-07-05 | 1981-02-03 | Luniversite Libre Bruxelles | Procede et installation pour la production de metaux reactifs par reduction de leurs halogenures |
US4442083A (en) * | 1982-11-04 | 1984-04-10 | Stauffer Chemical Company | Method of desulfurizing waste gases containing sulfur dioxide |
US4442082A (en) * | 1982-12-27 | 1984-04-10 | Sri International | Process for obtaining silicon from fluosilicic acid |
JPS6089529A (ja) * | 1983-10-21 | 1985-05-20 | Mitsubishi Metal Corp | 金属チタンの製造法 |
-
1988
- 1988-07-08 CA CA000571625A patent/CA1328561C/fr not_active Expired - Fee Related
- 1988-07-14 AU AU19044/88A patent/AU618541B2/en not_active Ceased
- 1988-07-15 EP EP88306510A patent/EP0299791B1/fr not_active Expired - Lifetime
- 1988-07-15 DE DE8888306510T patent/DE3875411T2/de not_active Expired - Fee Related
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8821611B2 (en) | 2005-10-06 | 2014-09-02 | Cristal Metals Inc. | Titanium boride |
US7753989B2 (en) | 2006-12-22 | 2010-07-13 | Cristal Us, Inc. | Direct passivation of metal powder |
US9127333B2 (en) | 2007-04-25 | 2015-09-08 | Lance Jacobsen | Liquid injection of VCL4 into superheated TiCL4 for the production of Ti-V alloy powder |
Also Published As
Publication number | Publication date |
---|---|
AU1904488A (en) | 1989-01-19 |
EP0299791A1 (fr) | 1989-01-18 |
DE3875411T2 (de) | 1993-04-08 |
DE3875411D1 (de) | 1992-11-26 |
AU618541B2 (en) | 1992-01-02 |
CA1328561C (fr) | 1994-04-19 |
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