CN114515835A - Molybdenum powder and preparation method thereof - Google Patents
Molybdenum powder and preparation method thereof Download PDFInfo
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- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 title claims abstract description 125
- 238000002360 preparation method Methods 0.000 title claims abstract description 13
- QXYJCZRRLLQGCR-UHFFFAOYSA-N dioxomolybdenum Chemical compound O=[Mo]=O QXYJCZRRLLQGCR-UHFFFAOYSA-N 0.000 claims abstract description 186
- 239000001257 hydrogen Substances 0.000 claims abstract description 49
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 49
- 239000000843 powder Substances 0.000 claims abstract description 45
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 43
- 239000002245 particle Substances 0.000 claims abstract description 28
- 238000000034 method Methods 0.000 claims abstract description 27
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 20
- 230000009467 reduction Effects 0.000 claims description 67
- JKQOBWVOAYFWKG-UHFFFAOYSA-N molybdenum trioxide Chemical compound O=[Mo](=O)=O JKQOBWVOAYFWKG-UHFFFAOYSA-N 0.000 claims description 34
- 239000002994 raw material Substances 0.000 claims description 10
- XUFUCDNVOXXQQC-UHFFFAOYSA-L azane;hydroxy-(hydroxy(dioxo)molybdenio)oxy-dioxomolybdenum Chemical compound N.N.O[Mo](=O)(=O)O[Mo](O)(=O)=O XUFUCDNVOXXQQC-UHFFFAOYSA-L 0.000 claims description 9
- 238000000889 atomisation Methods 0.000 claims description 7
- 238000010438 heat treatment Methods 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 2
- 239000013078 crystal Substances 0.000 abstract description 17
- 238000009826 distribution Methods 0.000 abstract description 12
- 230000008569 process Effects 0.000 abstract description 12
- 238000005245 sintering Methods 0.000 abstract description 11
- 230000015572 biosynthetic process Effects 0.000 abstract description 2
- 230000002349 favourable effect Effects 0.000 abstract 1
- 238000002474 experimental method Methods 0.000 description 21
- 238000006243 chemical reaction Methods 0.000 description 16
- 238000011946 reduction process Methods 0.000 description 13
- 238000011068 loading method Methods 0.000 description 9
- 229910052750 molybdenum Inorganic materials 0.000 description 9
- 239000011733 molybdenum Substances 0.000 description 9
- 239000002243 precursor Substances 0.000 description 7
- 230000009286 beneficial effect Effects 0.000 description 6
- RKTYLMNFRDHKIL-UHFFFAOYSA-N copper;5,10,15,20-tetraphenylporphyrin-22,24-diide Chemical compound [Cu+2].C1=CC(C(=C2C=CC([N-]2)=C(C=2C=CC=CC=2)C=2C=CC(N=2)=C(C=2C=CC=CC=2)C2=CC=C3[N-]2)C=2C=CC=CC=2)=NC1=C3C1=CC=CC=C1 RKTYLMNFRDHKIL-UHFFFAOYSA-N 0.000 description 6
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 5
- 150000002431 hydrogen Chemical class 0.000 description 5
- 239000001301 oxygen Substances 0.000 description 5
- 229910052760 oxygen Inorganic materials 0.000 description 5
- 239000007789 gas Substances 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 238000005507 spraying Methods 0.000 description 4
- 238000005054 agglomeration Methods 0.000 description 3
- 230000002776 aggregation Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- 238000009776 industrial production Methods 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 238000007873 sieving Methods 0.000 description 3
- 238000002156 mixing Methods 0.000 description 2
- 230000036632 reaction speed Effects 0.000 description 2
- 238000002411 thermogravimetry Methods 0.000 description 2
- 238000013329 compounding Methods 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000000748 compression moulding Methods 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- XLYOFNOQVPJJNP-ZSJDYOACSA-N heavy water Substances [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 description 1
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910000476 molybdenum oxide Inorganic materials 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- PQQKPALAQIIWST-UHFFFAOYSA-N oxomolybdenum Chemical compound [Mo]=O PQQKPALAQIIWST-UHFFFAOYSA-N 0.000 description 1
- 238000004886 process control Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/20—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds
- B22F9/22—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds using gaseous reductors
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Abstract
The invention provides molybdenum powder and a preparation method thereof, comprising the following steps: step 1, adding water accounting for 0-10% of the mass of molybdenum dioxide into molybdenum dioxide powder to obtain hydrous molybdenum dioxide powder; and 2, gradually adding the hydrous molybdenum dioxide powder to 950-1050 ℃ in a hydrogen atmosphere to obtain the reduced molybdenum powder. The method eliminates the occurrence of a large amount of molybdenum powder aggregates and the influence on the growth of molybdenum powder particles caused by the rapid formation of a large amount of molybdenum powder crystal nuclei when molybdenum dioxide is reduced in a strong reducing atmosphere, and effectively controls the particle size distribution of the molybdenum powder, so that the shape and the particle size distribution of the molybdenum powder are more favorable for the forming and sintering processes.
Description
Technical Field
The invention belongs to the field of metallurgy, and relates to molybdenum powder and a preparation method thereof.
Background
In the molybdenum metal processing deformation process, the molybdenum processing technological parameters and quality mainly depend on the density, hardness, grain number, metal interstitial impurity elements and the like of a molybdenum sintering blank, the density, hardness, grain number and interstitial impurity elements of the molybdenum sintering blank are mainly determined by the Ferris particle size, particle size distribution, specific surface area, molybdenum powder morphology and interstitial element oxygen content of molybdenum powder, and the molybdenum powder is mainly prepared by hydrogen reduction of high-purity molybdenum oxide, so that the oxygen content is the interstitial impurity which influences the most in the molybdenum processing process.
At present, the most important method for preparing molybdenum powder in China is high-purity molybdenum trioxide, and the molybdenum powder is prepared by a high-purity hydrogen double-reduction method. The process flow is that the molybdenum trioxide is reduced into molybdenum dioxide under the condition of hydrogen at the temperature of 350-650 ℃ for the first reduction; the second reduction is carried out at the temperature of above 650 ℃, and under the condition of hydrogen, the molybdenum dioxide is reduced into molybdenum powder, and the reaction is as follows:
MoO3(s)+H2(g)→MoO2(s)+H2O(g) (1)
MoO2(s)+2H2→Mo(s)+2H2O(g) (2)
because the molybdenum powder is molybdenum dioxide directly reduced into molybdenum powder by hydrogen, in order to ensure that the reaction of the equations (1) and (2) is complete and the operation process of the reaction process is safe, the hydrogen consumption is more than 10 times more than the actual consumption, so that the reactions of the equations (1) and (2) are carried out under the condition of absolute excess hydrogen, the water vapor generated by the reactions is quickly discharged along with the hydrogen, particularly, the reaction of the equation (2) is gradually increased along with the temperature, the reaction speed is increased, the reaction of the equation (2) can only be carried out in the forward direction, the influence of the reverse reaction relative to the forward reaction can be almost ignored, the reverse reaction conditions of the generation and the growth of molybdenum powder crystal nuclei in the molybdenum powder reduction process are broken, the molybdenum dioxide hydrogen reduces the molybdenum powder into a large number of crystal nuclei, the crystal nuclei can not grow, and finally forms molybdenum powder aggregates, the molybdenum powder crystal grain growth is deteriorated, and the molybdenum powder particle distribution range is damaged, the molybdenum powder particles are easy to agglomerate and agglomerate, and the agglomerated molybdenum powder is not beneficial to gas discharge during sintering, so that the sintering density is influenced, and the later sintering molding is not beneficial.
Disclosure of Invention
In order to solve the technical problems in the prior art, the invention provides molybdenum powder and a preparation method thereof, which can eliminate the occurrence of a large amount of molybdenum powder aggregates and the influence on the growth of molybdenum powder particles caused by the rapid formation of a large amount of molybdenum powder crystal nuclei when molybdenum dioxide is reduced in a strong reducing atmosphere, and effectively control the particle size distribution of the molybdenum powder, so that the shape and the particle size distribution of the molybdenum powder are more beneficial to the forming and sintering processes.
The invention is realized by the following technical scheme:
a preparation method of molybdenum powder comprises the following steps:
step 1, adding water accounting for 0-10% of the mass of molybdenum dioxide into molybdenum dioxide powder to obtain hydrous molybdenum dioxide powder;
and 2, gradually heating the hydrous molybdenum dioxide powder to 950-1050 ℃ in a hydrogen atmosphere to obtain reduced molybdenum powder.
Preferably, in the step 1, the addition amount of the water is 5-8% of the mass of the molybdenum dioxide.
Preferably, in the step 1, water is sprayed into the molybdenum dioxide powder by an atomization method.
Preferably, in step 1, the preparation method of the molybdenum dioxide powder comprises: molybdenum trioxide roasted by ammonium dimolybdate is used as an initial raw material and is obtained by hydrogen reduction, and the dew point of the adopted hydrogen is +35 ℃ to +45 ℃.
Preferably, in the step 1, the specific surface area of the molybdenum dioxide powder is 0.20-0.25 m2/g。
Preferably, step 2 specifically comprises: taking a reduction furnace tube as a reactor, wherein the temperature of the reduction furnace tube is gradually increased from one end to the other end, the temperature of the low-temperature end of the reduction furnace tube is 650 ℃, and the temperature of the high-temperature end of the reduction furnace tube is 950-1050 ℃; introducing hydrogen into the reduction furnace tube, adding hydrous molybdenum dioxide powder into the low-temperature end of the reduction furnace tube and gradually moving towards the high-temperature end of the reduction furnace tube, wherein the product obtained at the high-temperature end of the reduction furnace tube is reduced molybdenum powder.
Preferably, the residence time of the molybdenum dioxide powder in the reduction furnace tube is 7 hours.
Preferably, in step 2, the reduced molybdenum powder is sieved by a 200-mesh sieve to obtain the molybdenum powder.
Further, the specific surface area of the obtained molybdenum powder is 0.15-0.32 m2(ii)/g, the Fisher's average particle size is 2.5-4.5 um.
The molybdenum powder obtained by the preparation method is adopted.
Compared with the prior art, the invention has the following beneficial effects:
the preparation method of the molybdenum powder of the invention heats the maximum temperature of the raw materials to 950-1050 ℃. According to research, 920 ℃ is the crystal phase transition temperature of the molybdenum powder, when the temperature in the reduction process is lower than 920 ℃, the shape of the molybdenum powder prepared by reduction inherits the shape of precursor molybdenum dioxide and is a monoclinic tetragonal crystal form, when the temperature in the reduction process of the molybdenum powder is higher than 920 ℃, the shape of the molybdenum powder prepared by hydrogen reduction is ellipsoidal, and when the temperature in the reduction process of the molybdenum powder is 920 ℃, the shape of the molybdenum powder prepared by hydrogen reduction is ellipsoidal, but few parts of the molybdenum powder are not completely converted into the ellipsoidal tetragonal columnar crystal form. In industrial production practice, the ellipsoidal molybdenum powder has better effect in compression molding and sintering compared with other molybdenum powder with two morphologies, so that the maximum temperature of reduction is set to be 950-1050 ℃, and the ellipsoidal molybdenum powder can be obtained, and the subsequent processing and forming are facilitated. On the other hand, in the reduction process of the molybdenum dioxide, in order to ensure the control of the generation rate of the molybdenum crystal nucleus, part of water is uniformly sprayed by an atomization method, so that the molybdenum powder has enough oxidation capacity under the strong reduction atmosphere of the hydrogen reduction of the molybdenum dioxide, the reverse reaction of the reaction in the formula (2) can be carried out to a certain extent, the generation rate of the molybdenum powder crystal nucleus is controlled, the phenomena that a large number of molybdenum powder crystal nuclei are rapidly formed during the reduction of the molybdenum dioxide under the strong reduction atmosphere and the aggregates in the molybdenum powder grow are generated and the influence on the growth of the molybdenum powder particles is eliminated, and the particle size distribution of the molybdenum powder is effectively controlled, so that the obtained molybdenum powder has no aggregates and is beneficial to the discharge of gas during sintering, and the appearance and the particle size distribution of the obtained molybdenum powder are more beneficial to the forming and sintering processes.
Furthermore, during the reduction process of the molybdenum trioxide, hydrogen with high dew point is adopted, so that the reverse reaction of the reaction in the formula (1) can be carried out to a certain extent, and the reduced molybdenum dioxide has no agglomeration phenomenon.
Drawings
FIG. 1 shows MoO in thermogravimetric analysis (TGA)3The precursor reduces the SEM of the molybdenum dioxide under the hydrogen condition; a is MoO obtained in experiment 12Crystal nucleus aggregates; b is MoO obtained in experiment 22；
FIG. 2 shows MoO in thermogravimetric analysis (TGA)2The SEM of the molybdenum powder is generated in the hydrogen reduction process; a is prepared at experiment 3 below 920 DEG CThe shape of molybdenum powder; b is the shape of the molybdenum powder prepared at the temperature of more than 920 ℃ in the experiment 4; c is the morphology of the molybdenum powder prepared at 920 ℃ in experiment 5;
FIG. 3 SEM of molybdenum powder prepared in example 1;
FIG. 4 SEM of molybdenum powder prepared in example 2;
FIG. 5 SEM of molybdenum powder prepared in example 3.
Detailed Description
For a further understanding of the invention, reference will now be made to the following examples, which are provided to illustrate further features and advantages of the invention, and are not intended to limit the scope of the invention as set forth in the following claims.
In order to find and solve the process control method and process parameters of the molybdenum powder generation process on the shape, size and particle size distribution range of the molybdenum powder particles, the invention simulates the industrial production process on a thermogravimetric analyzer to find an effective, simple and easy-to-operate method.
The thermogravimetric analyzer experiment process is as follows:
experiment 1
Adding high-purity molybdenum trioxide prepared by decomposing ammonium dimolybdate serving as an initial raw material into a thermogravimetric analyzer, introducing hydrogen with a dew point of-60 ℃, gradually heating to 550 ℃, and reducing molybdenum trioxide into molybdenum dioxide powder at 350-550 ℃, wherein SEM is shown in figure 1 a.
Experiment 2
Adding high-purity molybdenum trioxide prepared by decomposing ammonium dimolybdate serving as an initial raw material into a thermogravimetric analyzer, introducing hydrogen with the dew point of +45 ℃, gradually heating to 550 ℃, and reducing molybdenum trioxide into molybdenum dioxide powder at 350-550 ℃, wherein SEM is shown in figure 1 b.
Experiment 3
The molybdenum dioxide obtained in experiment 2 is added into a thermogravimetric analyzer, hydrogen with dew point of-60 ℃ is introduced, the temperature is gradually increased to 910 ℃, and the molybdenum dioxide is reduced into molybdenum powder at 650-910 ℃, wherein SEM is shown in figure 2 a.
Experiment 4
The molybdenum dioxide obtained in experiment 2 was added to a thermogravimetric analyzer, hydrogen gas with dew point of +35 ℃ was introduced, the temperature was gradually raised to 950 ℃, and the molybdenum dioxide was reduced to molybdenum powder at 650 ℃ to 950 ℃, and SEM is shown in fig. 2 b.
Experiment 5
The molybdenum dioxide obtained in experiment 2 was added to a thermogravimetric analyzer, hydrogen gas with dew point of +35 ℃ was introduced, the temperature was gradually raised to 920 ℃, and the molybdenum dioxide was reduced to molybdenum powder at 650-920 ℃, and SEM is shown in fig. 2 c.
The result of the experiment of simulating the hydrogen reduction of the molybdenum powder by the thermogravimetric analyzer is as follows:
in the primary reduction process of experiment 1 and experiment 2, except that the dew point of hydrogen is different, other process parameters are the same, molybdenum dioxide obtained by reduction in hydrogen with the dew point of +45 ℃ in experiment 2 has no agglomeration phenomenon, as shown in figure 1b, while molybdenum dioxide obtained by reduction in hydrogen with the dew point of-60 ℃ in experiment 1 has serious agglomeration phenomenon, as shown in figure 1 a. In addition, as can be seen from fig. 1, in the preparation of the molybdenum dioxide powder by using the high-purity molybdenum trioxide decomposed and prepared by using ammonium dimolybdate as an initial raw material as a precursor and adopting primary hydrogen reduction, the molybdenum dioxide inherits the crystal form of the molybdenum trioxide precursor, and the molybdenum trioxide inherits the sheet-like morphology characteristic that the ammonium dimolybdate is in a monoclinic tetragonal form.
In the secondary reduction process of experiments 3-5, the experimental process parameters are the same except that the reduction temperature and the hydrogen dew point are different. As can be seen from fig. 2, in the preparation of molybdenum powder by using secondary hydrogen reduction, when the temperature in the reduction process is less than 920 ℃, the morphology of the molybdenum powder prepared by reduction inherits the morphology of precursor molybdenum dioxide, and the crystal form of the precursor molybdenum dioxide inherits the monoclinic tetragonal crystal form of the initial raw material ammonium dimolybdate, so that the morphology of the reduced molybdenum powder is tetragonal, as shown in fig. 2 a; when the temperature of the molybdenum powder in the reduction process is higher than 920 ℃, the molybdenum powder prepared by hydrogen reduction is in an ellipsoidal shape, as shown in figure 2 b; when the temperature of the molybdenum powder in the reduction process is 920 ℃, the molybdenum powder prepared by hydrogen reduction is in an ellipsoid shape, but few parts of the molybdenum powder are not completely converted into an ellipsoid-shaped tetragonal columnar crystal form, as shown in fig. 2 c. From fig. 2a and fig. 2b, it can be seen that the particle sizes of the molybdenum powders obtained at different dew points of hydrogen are different, and meanwhile, when the secondary reduction temperature of experiment 4 is 950 ℃, the oxygen content of the molybdenum powders is less than 1500 ppm.
Combined thermogravimetric analysisThe experimental results and industrial production practices show that the appearance of the once-reduced molybdenum dioxide is better than that of the molybdenum dioxide shown in figure 1a in use effect as shown in figure 1b, and the specific surface of a laser particle size analyzer is not more than 0.35m2A/g, preferably 0.2 to 0.25m2(iv) g; the secondary reduction molybdenum powder is sorted from poor to good according to the using effects of compression and sintering as follows: FIG. 2-a < FIG. 2-c < FIG. 2-b.
Therefore, during the reduction process of the molybdenum powder, the size and the particle size distribution of the molybdenum powder can be controlled by the amount of water vapor in the reduction furnace, and the morphology of the product is controlled by the reduction temperature.
According to research, the control of water quantity through the dew point of hydrogen causes inaccurate water quantity control due to the problem of water condensation, because the water is added into molybdenum dioxide in the later actual production.
According to the research results, the final molybdenum powder preparation method comprises the following steps:
step 1, uniformly spraying pure water accounting for 0-10 wt% (preferably 5-8 wt%) of the mass of molybdenum dioxide into molybdenum dioxide powder by adopting an atomization method to obtain hydrous molybdenum dioxide powder; specific Surface Area (SSA) of molybdenum dioxide not more than 0.35m2A specific ratio of 0.20 to 0.25 m/g2/g；
Step 2, introducing hydrogen into a reduction furnace tube, filling the hydrous molybdenum dioxide powder obtained in the step 1 into a magnetic boat, adding the hydrous molybdenum dioxide powder into the low-temperature end of the reduction furnace tube, moving the hydrous molybdenum dioxide powder to the high-temperature end of the reduction furnace tube at a certain speed, reducing the molybdenum dioxide in a hydrogen reduction atmosphere, and sieving the obtained product with a 200-mesh sieve to obtain molybdenum powder; the temperature of the reduction furnace tube is gradually increased from one end to the other end, the temperature of the low temperature end of the reduction furnace tube is 650 ℃, and the temperature of the high temperature end of the reduction furnace tube is 950-1050 ℃;
The hydrogen flow rate in the reduction furnace tube is 20-25 Nm3H; the loading amount of the molybdenum dioxide is 2.0 kg/boat; reduction speed: 2 boats/30-35 min, the specific surface area of the obtained molybdenum powder is 0.15-0.32 m2(ii)/g, the Fisher's average particle size is 2.5-4.5 um. The residence time of the magnetic boat in the reduction furnace tube is 7 hours.
The molybdenum dioxide powder is obtained by using molybdenum trioxide roasted by ammonium dimolybdate as an initial raw material and reducing the molybdenum trioxide by using hydrogen, wherein the dew point of the adopted hydrogen is +35 ℃ to +45 ℃.
Example 1
In the embodiment, molybdenum trioxide roasted by ammonium dimolybdate is used as an initial raw material, molybdenum dioxide is used as a precursor for molybdenum powder reduction, and a hydrogen reduction method is adopted to produce molybdenum powder.
Step 1, uniformly spraying pure water accounting for 5% of the mass of molybdenum dioxide into molybdenum dioxide powder by adopting an atomization method to obtain hydrous molybdenum dioxide powder; the specific surface area of the molybdenum dioxide is 0.20-0.25 m2/g；
Step 2, introducing the reducing furnace tube with the flow of 20-25 Nm3Hydrogen gas of/h, loading the hydrous molybdenum dioxide powder obtained in the step (1) into a magnetic boat according to the boat loading amount of 2.0 kg/boat, adding the low-temperature end of a reduction furnace tube, moving the hydrous molybdenum dioxide powder to the high-temperature end of the reduction furnace tube at a certain speed, keeping the magnetic boat in the reduction furnace tube for 7 hours, loading the hydrous molybdenum dioxide powder into the magnetic boat according to the speed of 2 boats/30-35 min, reducing the molybdenum dioxide in a hydrogen reduction atmosphere, and sieving the obtained product with a 200-mesh sieve to obtain molybdenum powder; the temperature of the reducing furnace gradually rises from one end to the other end, the temperature of the low-temperature end of the reducing furnace tube is 650 ℃, and the temperature of the high-temperature end of the reducing furnace tube is 1050 ℃.
The Fischer average particle size of the molybdenum powder obtained in the embodiment is 2.5-3.5 um, and the Bulk Density: 1.2g/cm3(determined as compounding time), tap density: TD > 3.0g/cm3The laser particle size distribution is d 10-3.5-5.5, d 50-10-25, d 90-20-25, and the Specific Surface Area (SSA) is 0.32m2And g, the oxygen content of the molybdenum powder before the furnace is less than 800PPm, and the shape of the molybdenum powder is ellipsoidal, as shown in figure 3.
The molybdenum powder is mainly used for domestic magnetron molybdenum caps.
Example 2
Step 1, uniformly spraying pure water accounting for 8% of the mass of molybdenum dioxide into molybdenum dioxide powder by adopting an atomization method to obtain hydrous molybdenum dioxide powder; the specific surface area of the molybdenum dioxide is 0.20-0.25 m2/g；
Step 2, introducing the reducing furnace tube with the flow of 20-25 Nm3H, loading the hydrous molybdenum dioxide powder obtained in the step 1 into a magnetic boat according to the boat loading amount of 2.0 kg/boat, adding the hydrous molybdenum dioxide powder into the low-temperature end of a reduction furnace tube, moving the hydrous molybdenum dioxide powder to the high-temperature end of the reduction furnace tube at a certain speed, and enabling the magnetic boat to still be loadedThe retention time in the original furnace tube is 7 hours, the raw material is loaded into a magnetic boat at the speed of 2 boat/30-35 min, molybdenum dioxide is reduced in a hydrogen reducing atmosphere, and the obtained product is sieved by a 200-mesh sieve to obtain molybdenum powder; the temperature of the reducing furnace gradually rises from one end to the other end, the temperature of the low-temperature end of the reducing furnace tube is 650 ℃, and the temperature of the high-temperature end of the reducing furnace tube is 1050 ℃.
The Fischer average particle size of the molybdenum powder obtained in the embodiment is 4.2-4.5 um, and the Bulk Density: 1.2 to 1.3g/cm3(determined by mixing time), the particle size distribution, d10 is 5-10, d50 is 10-25, d90 is 40-45, and the Specific Surface Area (SSA) is 0.15-0.23 m2And g, the oxygen content of the molybdenum powder before the furnace is less than 800PPm, and the shape of the molybdenum powder is ellipsoidal, as shown in figure 4. The water content of this example is greater than that of example 1, and the resulting molybdenum powder has an increased fisher's average particle size.
The special molybdenum powder mainly used for high-grade pure molybdenum plates and special-shaped pieces is obtained by the embodiment.
Example 3
Step 1, uniformly spraying pure water accounting for 10% of the mass of molybdenum dioxide into molybdenum dioxide powder by adopting an atomization method to obtain hydrous molybdenum dioxide powder; the specific surface area of the molybdenum dioxide is 0.20-0.25 m2/g；
Step 2, introducing the reducing furnace tube with the flow of 20-25 Nm3Hydrogen gas of/h, loading the hydrous molybdenum dioxide powder obtained in the step (1) into a magnetic boat according to the boat loading amount of 2.0 kg/boat, adding the low-temperature end of a reduction furnace tube, moving the hydrous molybdenum dioxide powder to the high-temperature end of the reduction furnace tube at a certain speed, keeping the magnetic boat in the reduction furnace tube for 7 hours, loading the hydrous molybdenum dioxide powder into the magnetic boat according to the speed of 2 boats/30-35 min, reducing the molybdenum dioxide in a hydrogen reduction atmosphere, and sieving the obtained product with a 200-mesh sieve to obtain molybdenum powder; the temperature of the reducing furnace gradually rises from one end to the other end, the temperature of the low-temperature end of the reducing furnace tube is 650 ℃, and the temperature of the high-temperature end of the reducing furnace tube is 1050 ℃.
The Fischer average particle size of the molybdenum powder obtained in the embodiment is 2.5-3.0 um, and the Bulk Density: 1.2g/cm3(determined by mixing time), because the molybdenum dioxide is added with excessive pure water, the reverse reaction speed of the reduction of the molybdenum dioxide is increased, the growth of molybdenum powder particles is reduced, as shown in figure 5, the reaction is performed, and in severe cases, the reaction can not be performedComplete or intermittent undercooking is carried out.
The present invention is described in detail with reference to the accompanying drawings, which are incorporated herein by reference, and the like, and the appended claims are intended to cover all such modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
Claims (10)
1. The preparation method of the molybdenum powder is characterized by comprising the following steps:
step 1, adding water accounting for 0-10% of the mass of molybdenum dioxide into molybdenum dioxide powder to obtain hydrous molybdenum dioxide powder;
and 2, gradually heating the hydrous molybdenum dioxide powder to 950-1050 ℃ in a hydrogen atmosphere to obtain reduced molybdenum powder.
2. The method for preparing molybdenum powder according to claim 1, wherein in the step 1, the amount of water added is 5-8% by mass of molybdenum dioxide.
3. The method for preparing molybdenum powder according to claim 1, wherein in the step 1, water is sprayed into the molybdenum dioxide powder by using an atomization method.
4. The method for preparing molybdenum powder according to claim 1, wherein in step 1, the method for preparing molybdenum dioxide powder comprises: molybdenum trioxide roasted by ammonium dimolybdate is used as an initial raw material and is obtained by hydrogen reduction, and the dew point of the adopted hydrogen is +35 ℃ to +45 ℃.
5. The method for preparing molybdenum powder according to claim 1, wherein in the step 1, the specific surface area of the molybdenum dioxide powder is 0.20 to 0.25m2/g。
6. The method for preparing molybdenum powder according to claim 1, wherein the step 2 specifically comprises: taking a reduction furnace tube as a reactor, wherein the temperature of the reduction furnace tube is gradually increased from one end to the other end, the temperature of the low-temperature end of the reduction furnace tube is 650 ℃, and the temperature of the high-temperature end of the reduction furnace tube is 950-1050 ℃; introducing hydrogen into the reduction furnace tube, adding hydrous molybdenum dioxide powder into the low-temperature end of the reduction furnace tube and gradually moving towards the high-temperature end of the reduction furnace tube, wherein the product obtained at the high-temperature end of the reduction furnace tube is reduced molybdenum powder.
7. The method of claim 1, wherein the molybdenum dioxide powder stays in the reduction furnace tube for 7 hours.
8. The method of preparing molybdenum powder of claim 1, wherein in step 2, the reduced molybdenum powder is sieved through a 200-mesh sieve to obtain molybdenum powder.
9. The method for preparing molybdenum powder according to claim 8, wherein the obtained molybdenum powder has a specific surface area of 0.15 to 0.32m2The Fisher average particle size is 2.5-4.5 um.
10. Molybdenum powder obtained by the production method according to any one of claims 1 to 9.
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5125965A (en) * | 1990-08-22 | 1992-06-30 | Cyprus Minerals Company | Method for maintaining fluidization in a fluidized bed reactor |
| CN101664809A (en) * | 2009-10-09 | 2010-03-10 | 株洲硬质合金集团有限公司 | Uniform macromeritic tungsten powder and method for preparing tungsten carbide powder |
| CN102369075A (en) * | 2008-10-17 | 2012-03-07 | H.C.施塔克公司 | Production of molybdenum metal powder |
| CN102601385A (en) * | 2012-04-18 | 2012-07-25 | 金堆城钼业股份有限公司 | Preparation method of molybdenum powder |
| CN103203455A (en) * | 2013-04-12 | 2013-07-17 | 金堆城钼业股份有限公司 | Method for manufacturing molybdenum powder |
| CN103273073A (en) * | 2013-06-30 | 2013-09-04 | 金堆城钼业股份有限公司 | Method for preparing molybdenum powder by molybdenum trioxide |
| CN103286317A (en) * | 2013-06-30 | 2013-09-11 | 金堆城钼业股份有限公司 | Method for preparing molybdenum powder by ammonium molybdate |
| CN103639417A (en) * | 2013-11-26 | 2014-03-19 | 金堆城钼业股份有限公司 | Preparation method for molybdenum powder with high surface activity |
| CN103952580A (en) * | 2014-04-28 | 2014-07-30 | 金堆城钼业股份有限公司 | Preparation method of rare earth molybdenum alloys with diffident grain sizes |
| CN104439266A (en) * | 2014-12-12 | 2015-03-25 | 金堆城钼业股份有限公司 | Preparation method of molybdenum powder large in particle size |
| KR20170128943A (en) * | 2016-05-16 | 2017-11-24 | 전북대학교산학협력단 | Method for manufacturing molybdenum powder with low oxygen concentration by high-temperature hydrogen reduction |
-
2022
- 2022-02-25 CN CN202210182291.5A patent/CN114515835B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5125965A (en) * | 1990-08-22 | 1992-06-30 | Cyprus Minerals Company | Method for maintaining fluidization in a fluidized bed reactor |
| CN102369075A (en) * | 2008-10-17 | 2012-03-07 | H.C.施塔克公司 | Production of molybdenum metal powder |
| CN101664809A (en) * | 2009-10-09 | 2010-03-10 | 株洲硬质合金集团有限公司 | Uniform macromeritic tungsten powder and method for preparing tungsten carbide powder |
| CN102601385A (en) * | 2012-04-18 | 2012-07-25 | 金堆城钼业股份有限公司 | Preparation method of molybdenum powder |
| CN103203455A (en) * | 2013-04-12 | 2013-07-17 | 金堆城钼业股份有限公司 | Method for manufacturing molybdenum powder |
| CN103273073A (en) * | 2013-06-30 | 2013-09-04 | 金堆城钼业股份有限公司 | Method for preparing molybdenum powder by molybdenum trioxide |
| CN103286317A (en) * | 2013-06-30 | 2013-09-11 | 金堆城钼业股份有限公司 | Method for preparing molybdenum powder by ammonium molybdate |
| CN103639417A (en) * | 2013-11-26 | 2014-03-19 | 金堆城钼业股份有限公司 | Preparation method for molybdenum powder with high surface activity |
| CN103952580A (en) * | 2014-04-28 | 2014-07-30 | 金堆城钼业股份有限公司 | Preparation method of rare earth molybdenum alloys with diffident grain sizes |
| CN104439266A (en) * | 2014-12-12 | 2015-03-25 | 金堆城钼业股份有限公司 | Preparation method of molybdenum powder large in particle size |
| KR20170128943A (en) * | 2016-05-16 | 2017-11-24 | 전북대학교산학협력단 | Method for manufacturing molybdenum powder with low oxygen concentration by high-temperature hydrogen reduction |
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