Method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste

Abstract

The invention provides a method for extracting rhenium from tungsten-molybdenum-rhenium alloy waste, which comprises the following steps: a three-temperature-zone tubular furnace comprises a high-temperature oxidation zone, a gas phase transition zone and a concentrated deposition zone, the temperature of the high-temperature oxidation zone is 600-900 DEG C, the temperature of the gas phase transition zone is 360-420 DEG C, and the temperature of the concentrated deposition zone is 25-150 DEG C; the three-temperature-zone tubular furnace is connected with oxygen-containing gas, the oxygen-containing gas sequentially passes through a high-temperature oxidation zone, a gas-phase transition zone and a centralized deposition zone, tungsten-molybdenum-rhenium alloy powder is placed in the three-temperature-zone tubular furnace, oxidation reaction is carried out in the high-temperature oxidation zone to obtain rhenium oxide, and the rhenium oxide is placed in the centralized deposition zone through airflow; the rhenium oxide and the tungsten-molybdenum oxide can be effectively separated through the high-temperature oxidation zone and the gas-phase transition zone, the purity of the rhenium oxide is improved, and separation of rhenium, molybdenum and tungsten is effectively achieved.

Description

Technical Field

[0001] The invention belongs to the field of rare metal recovery, and in particular relates to a method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste. Background Art

[0002] Rhenium is a rare metal with a content of only 1×10 -9 , with a melting point of about 3180°C. Due to its high heat resistance, high corrosion resistance, high hardness and mechanical strength, rhenium is widely used in high-temperature alloys, petroleum catalysis, metallurgy, electronics and other fields. However, rhenium resources are not abundant, and there is no single independent mineral with mining value. Some of it exists in other deposits, and some comes from the recycling of rhenium-containing alloy waste. With the scarcity of rhenium-containing primary mineral resources, the recovery of rhenium from rhenium-containing alloy waste has received increasing attention. Rhenium resources in my country are scarce, and with the development of the aerospace industry and the advancement of science and technology in the fields of chemical industry and medicine, the demand for rhenium is increasing, which makes the recycling of rhenium in rhenium-containing alloy waste particularly important.

[0003] The unique physical and chemical properties of rhenium make its recovery process usually complicated and difficult. At present, the technologies for recovering rhenium from rhenium-containing alloy waste mainly include pyrometallurgy and hydrometallurgy. Pyrometallurgy is a widely used method for recovering rare metals. Pyrometallurgy is carried out under high temperature conditions. During the roasting process, the rhenium in the rhenium-containing waste is easily oxidized to form volatile and water-soluble Re2O7 gas. Re2O7 is leached with ammonia or water, and rhenium is enriched in the solution in the form of ammonium perrhenate or perrhenic acid. Evaporation, concentration and crystallization are carried out to obtain ammonium perrhenate or perrhenic acid crystals, and finally metallic rhenium can be obtained by hydrogen reduction. The process principle of hydrometallurgical recovery of rhenium is to use oxidizing acid or alkali to leach rhenium in the waste, so that rhenium is in the solution as ReO4 - It exists in the form of, and then solvent extraction, ion exchange, chemical precipitation and other methods are used to separate and enrich rhenium from the rhenium-containing solution.

[0004] Among them, in the tungsten-molybdenum-rhenium alloy waste, due to the extremely similar chemical properties of tungsten and rhenium, they each exist in the form of acid ions in the solution, and the properties of the salt compounds formed are also very similar. Therefore, if traditional hydrometallurgy is used to recover rhenium, such as solvent extraction or ion exchange, to achieve the purpose of completely separating and extracting the two metals separately, the technology becomes more complicated, and it is difficult to make breakthrough progress in the process; using pyrometallurgy, there are problems such as low tungsten-rhenium separation efficiency, insufficient rhenium recovery rate and purity. At the same time, molybdenum and rhenium have high and similar melting points. The melting point of molybdenum is about 2620℃, and the melting point of rhenium is 3180℃. Both are high-melting-point metals. In the separation process, higher temperatures and energy are required to melt or change their states, which increases the difficulty and cost of separation, and also puts high demands on the high-temperature resistance of the equipment. In addition, the associated relationship between molybdenum and rhenium makes it difficult to completely separate them when pre-treating the ore. For example, during the mineral processing process, molybdenum and rhenium may be simultaneously enriched in the same concentrate. The subsequent separation process will have to deal with a higher concentration of mixed solution, which increases the difficulty of separation. Summary of the invention

[0005] The technical problem to be solved by the present invention is how to extract rhenium oxide from tungsten-molybdenum-rhenium alloy waste.

[0006] The present invention solves the above technical problems through the following technical means:

[0007] The present invention provides a method for extracting rhenium from tungsten-molybdenum-rhenium alloy waste, comprising the following steps:

[0008] The three-temperature zone tubular furnace comprises a high-temperature oxidation zone, a gas phase transition zone and a concentrated deposition zone, wherein the temperature of the high-temperature oxidation zone is 600-900°C, the temperature of the gas phase transition zone is 360-420°C, and the temperature of the concentrated deposition zone is 25-150°C; the three-temperature zone tubular furnace is connected to an oxygen-containing gas, and the oxygen-containing gas sequentially passes through the high-temperature oxidation zone, the gas phase transition zone and the concentrated deposition zone, and a tungsten-molybdenum-rhenium alloy powder is placed in the high-temperature oxidation zone of the three-temperature zone tubular furnace to undergo an oxidation reaction to obtain rhenium oxide, and the rhenium oxide is deposited in the concentrated deposition zone through an airflow.

[0009] Beneficial effects: The present invention places tungsten-molybdenum-rhenium alloy powder in a high-temperature oxidation zone for oxidation reaction, and the corresponding metals react to generate oxides. At high temperatures, tungsten oxide is stable and cannot sublimate, so it remains in the high-temperature oxidation zone. Molybdenum oxide partially sublimates, while rhenium oxide sublimates into gaseous oxides, which flow to the gas phase transition zone through the airflow. After the gas phase transition zone is cooled once, the molybdenum oxide is deposited in the gas phase transition zone, while the rhenium oxide does not change. As the airflow finally flows to the concentrated deposition zone, it is cooled again and deposited to obtain rhenium oxide.

[0010] The present invention can effectively separate rhenium oxide and tungsten-molybdenum oxide through the high-temperature oxidation zone and the gas phase transition zone, improve the purity of rhenium oxide, and effectively realize the separation of rhenium oxide and molybdenum-tungsten oxide.

[0011] Preferably, the tungsten-molybdenum-rhenium alloy waste is first soaked in dilute hydrochloric acid for 0.5 to 2 hours, and washed with acetone, and then filtered and dried to obtain tungsten-molybdenum-rhenium alloy powder.

[0012] Preferably, the insulation time of the high temperature oxidation zone is 1 to 10 hours.

[0013] Preferably, the heating rate of the high temperature oxidation zone is 5 to 50° C. / min.

[0014] Preferably, the lengths of the high temperature oxidation zone, the gas phase transition zone and the concentrated deposition zone are 40 to 2000 mm.

[0015] Beneficial effects: The present invention ensures maximum recovery and improves the recovery rate of rhenium by adjusting the length of the gas phase transition zone and the concentrated deposition zone.

[0016] Preferably, the flow rate of the oxygen-containing gas is 100-1000 ml / min.

[0017] Preferably, the oxygen-containing gas is oxygen or air.

[0018] Preferably, attapulgite is placed in the gas phase transition zone to adsorb molybdenum oxide.

[0019] Beneficial effect: The present invention adds attapulgite in the gas phase transition zone to adsorb molybdenum oxide, thereby improving the purity of molybdenum oxide.

[0020] Preferably, the temperature of the high temperature oxidation zone is first increased to 500° C. at a rate of 10° C. / min, and then increased to 600-900° C. at a rate of 5° C. / min.

[0021] Preferably, the temperature of the high-temperature oxidation zone is 800°C, the temperature of the gas phase transition zone is 380°C, and the temperature of the concentrated deposition zone is 150°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of a method and device for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste in an embodiment;

[0023] Figure 2 is a microscopic morphology of rhenium oxide in the concentrated deposition area in the embodiment;

[0024] Figure 3 is a distribution diagram of rhenium oxide elements in the concentrated deposition area in the embodiment;

[0025] Figure 4 This is an element XRD phase analysis diagram of the rhenium oxidation zone in the concentrated deposition zone in the embodiment;

[0026] Figure 5 is a microscopic morphology of molybdenum oxide in the gas phase transition zone in the embodiment;

[0027] Figure 6 is a distribution diagram of molybdenum oxide elements in the gas phase transition zone in the embodiment;

[0028] Figure 7 : These are the SEM images of tungsten and molybdenum oxides in the high temperature oxidation zone in the embodiment and the corresponding EDS energy spectrum. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Unless otherwise specified, the test materials and reagents used in the following examples can be obtained from commercial sources.

[0031] If no specific techniques or conditions are specified in the examples, they can be carried out according to the techniques or conditions described in the literature in the art or according to the product instructions.

[0032] Example 1

[0033] This embodiment provides a method for extracting rhenium from tungsten-molybdenum-rhenium alloy waste, and the specific steps are as follows:

[0034] (1) The tungsten-molybdenum-rhenium alloy waste is soaked in dilute hydrochloric acid for 1 hour and washed twice with acetone to remove oxides, foreign substances and other impurities on the surface of the waste. After filtering, the waste is placed in a vacuum drying oven and fully dried until the quality does not change, thereby obtaining a tungsten-molybdenum-rhenium alloy powder.

[0035] (2) 100 g of tungsten-molybdenum-rhenium alloy powder (containing about 1 g of rhenium) was spread flat on the bottom of the corundum firing boat to ensure a sufficiently large contact area, and then the firing boat was placed in the high-temperature oxidation zone of a three-zone tubular furnace for high-temperature oxidation sublimation separation. The temperature was set to 800°C, and the heating rate was increased from 10°C / min to 500°C, and then from 500°C to 800°C at 5°C / min. The insulation time range was 1 h. At the same time, the three-zone tubular furnace was connected to the air, and the air flow rate was 100 ml / min. The length of the high-temperature oxidation zone was 400 mm.

[0036] Tungsten, molybdenum and rhenium alloy powder is oxidized in the high-temperature oxidation zone to generate corresponding oxides, and tungsten, molybdenum and rhenium are initially separated by air flow. At 800°C, rhenium oxide is completely sublimated to generate gas, while tungsten oxide does not react at all and remains in the high-temperature oxidation zone. Molybdenum oxide is partially sublimated to generate gas, and the gaseous oxide flows to the gas phase transition zone with the air flow. The temperature of the gas phase transition zone is 380°C and the length is 400mm. When the gaseous molybdenum oxide enters the gas phase transition zone, the temperature is reduced so that the gaseous molybdenum oxide is condensed into a solid and deposited in the gas phase transition zone. The gaseous rhenium oxide does not change at all and flows to the concentrated deposition zone with the air flow. The temperature of the concentrated deposition zone is 150°C and the length is 400mm. When the gaseous rhenium oxide enters the concentrated deposition zone, the temperature is further reduced so that the gaseous rhenium oxide is condensed into a solid and deposited in the concentrated deposition zone. The deposited rhenium oxide has good distribution concentration and controllable crystalline state. Figure 2 and 3 shown.

[0037] The metal rhenium powder prepared by the method of this embodiment is characterized as follows: the rhenium oxide powder has good crystallinity, a purity of about 99.1%, and a rhenium recovery rate of 85.9%.

[0038] Example 2

[0039] This embodiment provides a method for extracting rhenium from tungsten-molybdenum-rhenium alloy waste, and the specific steps are as follows:

[0040] (1) The tungsten-molybdenum-rhenium alloy waste is soaked in dilute hydrochloric acid for 2 hours and washed twice with acetone to remove oxides, foreign substances and other impurities on the surface of the waste. After filtering, the waste is placed in a vacuum drying oven and fully dried until the quality does not change, thereby obtaining a tungsten-molybdenum-rhenium alloy powder.

[0041] (2) 100 g of tungsten-molybdenum-rhenium alloy powder (containing about 1 g of rhenium) was spread flat on the bottom of the corundum firing boat to ensure a sufficiently large contact area, and then the firing boat was placed in the high-temperature oxidation zone of a three-zone tubular furnace for high-temperature oxidation sublimation separation. The temperature was set to 900°C, and the heating rate was increased from 10°C / min to 500°C, and then from 500°C to 900°C at 5°C / min, and the holding time was 2 h. At the same time, the three-zone tubular furnace was connected to the air, and the air flow rate was 500 ml / min. The length of the high-temperature oxidation zone was 400 mm.

[0042] Tungsten, molybdenum and rhenium alloy powder is oxidized in the high-temperature oxidation zone to generate corresponding oxides, and tungsten, molybdenum and rhenium are initially separated by air flow. At 900°C, rhenium oxide is completely sublimated to generate gas, while tungsten oxide does not react at all and remains in the high-temperature oxidation zone. Molybdenum oxide is partially sublimated to generate gas, and the gaseous oxide flows to the gas phase transition zone with the air flow. The temperature of the gas phase transition zone is 380°C and the length is 400mm. When the gaseous molybdenum oxide enters the gas phase transition zone, the temperature is reduced so that the gaseous molybdenum oxide is condensed into a solid and deposited in the gas phase transition zone. The gaseous rhenium oxide does not change at all and flows to the concentrated deposition zone with the air flow. The temperature of the concentrated deposition zone is 150°C and the length is 400mm. When the gaseous rhenium oxide enters the concentrated deposition zone, the temperature is further reduced so that the gaseous rhenium oxide is condensed into a solid and deposited in the concentrated deposition zone. The deposited rhenium oxide has good distribution concentration and controllable crystal state.

[0043] The metal rhenium oxide powder prepared by the method of this embodiment is characterized in that the rhenium oxide powder has good crystallinity, a purity of about 98.9%, and a rhenium recovery rate of 79.6%.

[0044] Example 3

[0045] This embodiment provides a method for extracting rhenium from tungsten-molybdenum-rhenium alloy waste, and the specific steps are as follows:

[0046] (1) The tungsten-molybdenum-rhenium alloy waste is soaked in dilute hydrochloric acid for 2 hours and washed twice with acetone to remove oxides, foreign substances and other impurities on the surface of the waste. After filtering, the waste is placed in a vacuum drying oven and fully dried until the quality does not change, thereby obtaining a tungsten-molybdenum-rhenium alloy powder.

[0047] (2) 100 g of tungsten-molybdenum-rhenium alloy powder (containing about 1 g of rhenium) was spread flat on the bottom of the corundum firing boat to ensure a sufficiently large contact area, and then the firing boat was placed in the high-temperature oxidation zone of a three-zone tubular furnace for high-temperature oxidation sublimation separation. The temperature was set to 700°C, and the heating rate was increased from 10°C / min to 500°C, and then from 500°C to 700°C at 5°C / min, and the holding time was 2 h. At the same time, the three-zone tubular furnace was connected to the air, and the air flow rate was 500 ml / min. The length of the high-temperature oxidation zone was 400 mm.

[0048] Tungsten, molybdenum and rhenium alloy powder is oxidized in the high-temperature oxidation zone to generate corresponding oxides, and tungsten, molybdenum and rhenium are initially separated by air flow. At 700°C, rhenium oxide is completely sublimated to generate gas, while tungsten oxide does not react at all and remains in the high-temperature oxidation zone. Molybdenum oxide is partially sublimated to generate gas, and the gaseous oxide flows to the gas phase transition zone with the air flow. The temperature of the gas phase transition zone is 380°C and the length is 400mm. When the gaseous molybdenum oxide enters the gas phase transition zone, the temperature is reduced so that the gaseous molybdenum oxide is condensed into a solid and deposited in the gas phase transition zone. The gaseous rhenium oxide does not change at all and flows to the concentrated deposition zone with the air flow. The temperature of the concentrated deposition zone is 150°C and the length is 400mm. When the gaseous rhenium oxide enters the concentrated deposition zone, the temperature is further reduced so that the gaseous rhenium oxide is condensed into a solid and deposited in the concentrated deposition zone. The deposited rhenium oxide has good distribution concentration and controllable crystal state.

[0049] The metal rhenium oxide powder prepared by the method of this embodiment is characterized in that the rhenium oxide powder has good crystallinity, a purity of about 98.91%, and a rhenium recovery rate of 66.31%.

[0050] Example 4

[0051] This embodiment provides a method for extracting rhenium from tungsten-molybdenum-rhenium alloy waste, and the specific steps are as follows:

[0052] (1) The tungsten-molybdenum-rhenium alloy waste is soaked in dilute hydrochloric acid for 1 hour and washed twice with acetone to remove oxides, foreign substances and other impurities on the surface of the waste. After filtering, the waste is placed in a vacuum drying oven and fully dried until the quality does not change, thereby obtaining a tungsten-molybdenum-rhenium alloy powder.

[0053] (2) 100 g of tungsten-molybdenum-rhenium alloy powder (containing about 1 g of rhenium) was spread flat on the bottom of the corundum firing boat to ensure a sufficiently large contact area, and then the firing boat was placed in the high-temperature oxidation zone of a three-zone tubular furnace for high-temperature oxidation sublimation separation. The temperature was set to 800°C, and the heating rate was increased from 10°C / min to 500°C, and then from 500°C to 800°C at 5°C / min. The insulation time range was 1 h. At the same time, the three-zone tubular furnace was connected to the air, and the air flow rate was 100 ml / min. The length of the high-temperature oxidation zone was 400 mm.

[0054] Tungsten, molybdenum and rhenium alloy powders are oxidized in a high-temperature oxidation zone to generate corresponding oxides, and tungsten, molybdenum and rhenium are initially separated by air flow. At 800°C, rhenium oxide is completely sublimated to generate gas, while tungsten oxide does not react at all and remains in the high-temperature oxidation zone. Molybdenum oxide is partially sublimated to generate gas, and the gaseous oxide flows to a gas phase transition zone with the air flow. The temperature of the gas phase transition zone is 380°C and the length is 800 mm. When the gaseous molybdenum oxide enters the gas phase transition zone, the temperature is reduced so that the gaseous molybdenum oxide is condensed into a solid and deposited in the gas phase transition zone. The gaseous rhenium oxide does not change at all and flows to a concentrated deposition zone with the air flow. The temperature of the concentrated deposition zone is 150°C and the length is 400 mm. When the gaseous rhenium oxide enters the concentrated deposition zone, the temperature is further reduced so that the gaseous rhenium oxide is condensed into a solid and deposited in the concentrated deposition zone. The deposited rhenium oxide has good distribution concentration and controllable crystallinity.

[0055] The metal rhenium powder prepared by the method of this embodiment is characterized as follows: the rhenium oxide powder has good crystallinity, a purity of about 99.5%, and a rhenium recovery rate of 88.6%.

[0056] Example 5

[0057] This embodiment provides a method for extracting rhenium from tungsten-molybdenum-rhenium alloy waste, and the specific steps are as follows:

[0058] (1) The tungsten-molybdenum-rhenium alloy waste is soaked in dilute hydrochloric acid for 1 hour and washed twice with acetone to remove oxides, foreign substances and other impurities on the surface of the waste. After filtering, the waste is placed in a vacuum drying oven and fully dried until the quality does not change, thereby obtaining a tungsten-molybdenum-rhenium alloy powder.

[0059] (2) 100 g of tungsten-molybdenum-rhenium alloy powder (containing about 1 g of rhenium) was spread flat on the bottom of the corundum firing boat to ensure a sufficiently large contact area, and then the firing boat was placed in the high-temperature oxidation zone of a three-zone tubular furnace for high-temperature oxidation sublimation separation. The temperature was set to 800°C, and the heating rate was increased from 10°C / min to 500°C, and then from 500°C to 800°C at 5°C / min. The insulation time range was 1 h. At the same time, the three-zone tubular furnace was connected to the air, and the air flow rate was 100 ml / min. The length of the high-temperature oxidation zone was 400 mm.

[0060] Tungsten, molybdenum and rhenium alloy powders are oxidized in the high-temperature oxidation zone to generate corresponding oxides, and the air flow makes the preliminary separation of tungsten, molybdenum and rhenium. At 800°C, the rhenium oxide is completely sublimated to generate gas, while the tungsten oxide does not react at all and remains in the high-temperature oxidation zone. The molybdenum oxide is partially sublimated to generate gas, and the gas oxide flows to the gas phase transition zone with the air flow. The temperature of the gas phase transition zone is 380°C and the length is 400mm. At the same time, attapulgite is added to the middle transition zone to further adsorb the molybdenum oxide. When the gaseous molybdenum oxide enters the gas phase transition zone, the temperature decreases so that the gaseous molybdenum oxide condenses into a solid and is deposited in the gas phase transition zone. The gaseous rhenium oxide does not change at all and flows to the concentrated deposition zone with the air flow. The temperature of the concentrated deposition zone is 150°C and the length is 400mm. When the gaseous rhenium oxide enters the concentrated deposition zone, the temperature further decreases so that the gaseous rhenium oxide condenses into a solid and is deposited in the concentrated deposition zone.

[0061] The metal rhenium powder prepared by the method of this embodiment is characterized as follows: the rhenium oxide powder has good crystallinity, a purity of about 99.6%, and a rhenium recovery rate of 85.3%.

[0062] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste, characterized in that: The following steps are involved: The three-temperature zone tubular furnace comprises a high-temperature oxidation zone, a gas phase transition zone and a concentrated deposition zone, wherein the temperature of the high-temperature oxidation zone is 600-900°C, the temperature of the gas phase transition zone is 360-420°C, and the temperature of the concentrated deposition zone is 25-150°C; the three-temperature zone tubular furnace is connected to an oxygen-containing gas, which passes through the high-temperature oxidation zone, the gas phase transition zone and the concentrated deposition zone in sequence, and a tungsten-molybdenum-rhenium alloy powder is placed in the high-temperature oxidation zone to undergo an oxidation reaction to obtain rhenium oxide, and the rhenium oxide is placed in the concentrated deposition zone through an airflow for deposition.

2. The method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste according to claim 1, characterized in that: The tungsten-molybdenum-rhenium alloy waste is firstly soaked in dilute hydrochloric acid for 0.5 to 2 hours, and then washed with acetone, and then filtered and dried to obtain tungsten-molybdenum-rhenium alloy powder.

3. The method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste according to claim 1, characterized in that: The high temperature oxidation zone is kept warm for 1 to 10 hours.

4. The method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste according to claim 1, characterized in that: The heating rate of the high temperature oxidation zone is 5-50°C / min.

5. The method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste according to claim 1, characterized in that: The lengths of the high temperature oxidation zone, the gas phase transition zone and the concentrated deposition zone are 40 to 2000 mm.

6. The method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste according to claim 1, characterized in that: The flow rate of the oxygen-containing gas is 100-1000 ml / min.

7. The method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste according to claim 1, characterized in that: The oxygen-containing gas is oxygen or air.

8. The method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste according to claim 1, characterized in that: The gas phase transition zone is placed with attapulgite to adsorb molybdenum oxide.

9. The method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste according to claim 4, characterized in that: The temperature of the high temperature oxidation zone is firstly increased to 500°C at a rate of 10°C / min, and then increased to 600-900°C at a rate of 5°C / min.

10. The method for extracting rhenium oxide from tungsten-molybdenum-rhenium alloy waste according to claim 9, characterized in that: The temperature of the high-temperature oxidation zone is 800°C, the temperature of the gas phase transition zone is 380°C, and the temperature of the concentrated deposition zone is 150°C.

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