Method for recovering molybdenum-rhenium alloy waste

Abstract

The invention discloses a method for recovering molybdenum-rhenium alloy waste, which realizes molybdenum-rhenium recovery through the steps of crushing, ball milling, sulfating roasting, water leaching and filter pressing treatment, ammoniation treatment, evaporative crystallization recovery, organic solvent dissolution, filter pressing and evaporation on the molybdenum-rhenium alloy waste, so that precious resources can be saved; and the mining of primary mineral products is reduced, so that the damage to the environment in the mining process is reduced, the accumulation of wastes can be reduced, and the pollution to land and water sources is alleviated. In addition, the technological innovation and optimization in the recycling process can promote the development of related industries. Therefore, the recycling of the molybdenum-rhenium alloy waste is not only an economically feasible measure, but also an environment-friendly sustainable development strategy.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal recycling, and particularly relates to a method for recycling molybdenum-rhenium alloy waste. Background Art

[0002] Molybdenum-rhenium alloy exhibits excellent thermal and electrical conductivity and corrosion resistance, and also has advantages such as high hardness and high temperature resistance. Therefore, it has been widely used in the manufacture of key components in the fields of aerospace, electronics, and nuclear power reactors. In addition, due to its excellent biocompatibility, significant progress has been made in the field of new medical materials in recent years. Currently, the recycling of molybdenum-rhenium alloy in the industry mainly uses chemical methods. After oxidizing and dissolving the molybdenum-rhenium alloy, the rhenium element is extracted in the form of rhenate, and finally, a series of metallurgical processes such as calcination and reduction are used to prepare pure metal rhenium powder. Such methods have a long process route, high costs, and low recovery rates due to the use of relatively complex extraction processes. At the same time, the extraction waste liquid generated during the extraction process is difficult to recycle, and if not properly treated, it will cause environmental pollution (see the literature, Chinese Journal of Process Engineering, Vol. 13, No. 6. Classification number: TQ013.1 Document code: A Article number: 1009-606X(2013)06-0969-05, "Leaching and Separation of Tungsten, Molybdenum, and Rhenium from Sulfuric Acid Leaching Residue of Spent Superalloy").

[0003] Both rhenium and molybdenum metals have relatively high market prices. Especially rhenium metal, as a rare metal, has a very low content in the earth's crust. The national annual output is only about 20 tons, and its unit price has long fluctuated around 10,000 yuan / kg. At the same time, both rhenium and molybdenum metals belong to heavy metals. If molybdenum-rhenium alloy waste is not properly treated, it will cause environmental pollution.

[0004] Therefore, the recycling of rhenium-molybdenum alloy waste not only has significant economic value but also has far-reaching significance in environmental protection. Summary of the Invention

[0005] (1) Technical problems to be solved: How to provide an efficient recycling method for molybdenum-rhenium alloy waste to solve the problem of waste of rhenium and molybdenum resources

[0006] (2) The technical solution adopted by the present invention is as follows: A method for recycling molybdenum-rhenium alloy waste, characterized in that it includes the following steps:

[0007] Step 1: Crushing. Weigh the waste containing molybdenum-rhenium alloy, and then crush the waste.

[0008] Step 2: Ball milling. After the waste is crushed, it is put into a ball mill for ball milling for 30 minutes. After the ball milling is completed, it is screened using a 50-mesh sieve to obtain the oversize and the undersize. The oversize needs to be returned to the ball mill for continuous ball milling.

[0009] Step 3: Sulfation roasting. The undersize product obtained in Step 2 is placed in a corundum crucible, and analytical pure concentrated sulfuric acid is added to the crucible with a solid-liquid ratio of 1:4. Then, the crucible lid is covered, and it is placed in a muffle furnace for roasting within the temperature range of 400°C to 800°C for 60 to 90 minutes. After roasting, sulfates are formed. Wait until it cools to room temperature.

[0010] Step 4: Water immersion and pressure filtration treatment. After the product of Step 3 is ground to 200 mesh, deionized water is added with a volume ratio of material to deionized water of 5:1. Subsequently, it is heated to 90°C and stirred for 2 hours, and then pressure filtration treatment is carried out using a filter press to obtain filtrate a (sulfate solution) and filter residue a (molybdenum-rhenium alloy residue and oxides). Filter residue a needs to be returned to the sulfation roasting process of Step 3 for re-treatment.

[0011] Step 5: Ammoniation treatment, evaporation and crystallization: The filtrate a obtained in Step 1 is subjected to ammoniation treatment. Ammonia gas is introduced and stirred, and at the same time, the pH value of filtrate a is monitored. When the pH value of filtrate a reaches 7, the introduction of ammonia gas is stopped. Then, filtrate a is transferred to an evaporating dish for heating and evaporation treatment until the liquid is completely evaporated to obtain light yellow crystal a (mixture of ammonium perrhenate and ammonium molybdate).

[0012] Step 6: Dissolution in organic solvent, pressure filtration, evaporation: The light yellow crystal a (mixture of ammonium perrhenate and ammonium molybdate) obtained in Step 5 is added to methanol or ethanol with a solid-liquid ratio set at 1:5. It is heated to 50°C and stirred for 1 hour. Subsequently, pressure filtration treatment is carried out using a filter press to obtain filtrate b and filter residue b. Filter residue b is a white crystal. After XRD (X-ray diffraction) detection, the peak positions are consistent with the main peak positions of the ammonium molybdate standard PDF card. Through ICP-MS testing, the molybdenum content is 44.42% to 47.56%, the purity of the obtained ammonium molybdate is 90% to 97%, and the molybdenum recovery rate is 92% to 97%. Filtrate b is transferred to an evaporating dish for heating and evaporation treatment until the liquid is completely evaporated to obtain white crystal C. This white crystal C is detected by XRD (X-ray diffraction), and its peak positions are consistent with the main peak positions of the ammonium perrhenate standard PDF card. Through ICP-MS testing, the rhenium content is 65.18% to 67.92%. After calculation, the purity of the obtained ammonium perrhenate is 95% to 97%, and the rhenium recovery rate is 93% to 98%. Since this step adopts the process of dissolution in organic solvent, pressure filtration, and evaporation with a higher recovery rate, it avoids the traditional extraction process with a lower recovery rate.

[0013] (3) Due to the adoption of the above technical solutions, the beneficial effects of the present invention are:

[0014] Since the present invention adopts the process of dissolution in organic solvent, pressure filtration, and evaporation with a higher recovery rate, it makes up for the defects of the traditional extraction process.

[0015] The white crystal C obtained in the present invention was detected by XRD (X-ray diffraction), and its peak positions were consistent with the main peak positions of the ammonium perrhenate standard PDF card. Through ICP-MS testing, the rhenium content was 65.18% to 67.32%. After calculation, the purity of the obtained ammonium perrhenate was 94% to 97%, and the rhenium recovery rate was 93% to 98% (rhenium recovery rate = mass of rhenium in the product ammonium perrhenate / mass of rhenium in the raw material molybdenum-rhenium alloy). The filter residue b in the present invention was a white crystal, which was detected by XRD (X-ray diffraction), and its peak positions were consistent with the main peak positions of the ammonium molybdate standard PDF card. Through ICP-MS testing, the molybdenum content was 44.42% to 47.56%. After calculation, the purity of the obtained ammonium molybdate was 90% to 97%, and the molybdenum recovery rate was 92% to 97% (molybdenum recovery rate = mass of molybdenum in the product ammonium molybdate / mass of molybdenum in the raw material molybdenum-rhenium alloy).

[0016] By recycling molybdenum-rhenium alloy waste, the present invention can not only save precious resources, reduce the exploitation of primary minerals, thereby reducing the environmental damage during the exploitation process, but also reduce the accumulation of waste and alleviate the pollution of land and water sources. In addition, the technological innovation and optimization during the recycling process can also promote the development of related industries. Therefore, the recycling of molybdenum-rhenium alloy waste is not only an economically feasible measure, but also an environmentally friendly sustainable development strategy. Brief Description of the Drawings

[0017] Figure 1 is the process flow chart of the present invention. Detailed Embodiments

[0018] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the drawings and embodiments.

[0019] As Figure 1 shown.

[0020] Example 1

[0021] A method for recycling molybdenum-rhenium alloy waste. The molybdenum-rhenium alloy waste is a defective product during the production process of a certain molybdenum industry company. The molybdenum content in the molybdenum-rhenium alloy waste is 54%, and the rhenium content is 42%. The method includes the following steps:

[0022] Step 1: Take 1 Kg of rhenium-molybdenum alloy waste. After crushing, put it into a ball mill and ball mill for 30 minutes, then screen it using a 50-mesh sieve. The oversize material is returned to the ball mill for continuous ball milling, and the undersize material is put into a corundum crucible. Then, add analytical pure concentrated sulfuric acid into the crucible, and set the solid-liquid ratio to 1:4. Cover the crucible lid, put it into a muffle furnace, and carry out sulfation roasting at a temperature of 400 °C for 90 minutes. After roasting is completed, wait for the product to cool to room temperature, grind it to 200 mesh, and then add deionized water. The volume ratio of the material to deionized water is 5:1. Subsequently, heat it to 90 °C and keep stirring for 2 hours, and then carry out pressure filtration using a filter press to obtain filtrate a and filter residue a. Filter residue a needs to be returned to the sulfation roasting process for reprocessing.

[0023] Step 2: Carry out ammoniation treatment on filtrate a obtained in Step 1. Introduce ammonia gas and stir, and at the same time monitor the pH value of filtrate a. When the pH value of filtrate a reaches 7, stop introducing ammonia gas. Then, transfer filtrate a to an evaporating dish and carry out heating evaporation treatment until the liquid is completely evaporated to obtain light yellow crystal a.

[0024] Step 3: Add methanol to the light yellow crystal a obtained in Step 2, with a solid-liquid ratio of 1:5. Heat it to 50 °C and keep stirring for 1 hour. Subsequently, carry out pressure filtration using a filter press to obtain filtrate b and filter residue b. Filter residue b is 0.91 Kg of white crystal. After being detected by XRD (X-ray diffraction), the peak positions are consistent with the main peak positions of the ammonium molybdate standard PDF card. Through ICP-MS testing, the molybdenum content is 44.42%. After calculation, the purity of the obtained ammonium molybdate is 90%, and the recovery rate of molybdenum is 92%.

[0025] Transfer filtrate b to an evaporating dish and carry out heating evaporation treatment until the liquid is completely evaporated to obtain 0.412 Kg of white crystal C. This white crystal C is detected by XRD (X-ray diffraction), and its peak positions are consistent with the main peak positions of the ammonium perrhenate standard PDF card. Through ICP-MS testing, the rhenium content is 65.18%. After calculation, the purity of the obtained ammonium perrhenate is 95%, and the recovery rate of rhenium is 93%.

[0026] Example 2

[0027] A method for recycling rhenium-molybdenum alloy waste. The rhenium-molybdenum alloy waste is a defective product in the production process of a certain molybdenum company. The molybdenum content in the rhenium-molybdenum alloy waste is 60%, and the rhenium content is 34%. The method includes the following steps:

[0028] Step 1: Take 1 Kg of rhenium-molybdenum alloy waste. After crushing, put it into a ball mill and ball mill for 30 minutes, then screen it using a 50-mesh sieve. The oversize material is returned to the ball mill for continuous ball milling, and the undersize material is put into a corundum crucible. Then, add analytical pure concentrated sulfuric acid into the crucible, and set the solid-liquid ratio to 1:4. Cover the crucible lid, put it into a muffle furnace, and carry out sulfation roasting at a temperature of 800 °C for 60 minutes. After roasting is completed, wait for the product to cool to room temperature, grind it to 200 mesh, and then add deionized water. The volume ratio of the material to deionized water is 5:1. Subsequently, heat it to 90 °C and keep stirring for 2 hours, and then carry out pressure filtration using a filter press to obtain filtrate a and filter residue a. Filter residue a needs to be returned to the sulfation roasting process for re-treatment.

[0029] Step 2: Carry out ammoniation treatment on filtrate a obtained in Step 1. Introduce ammonia gas and stir, and at the same time monitor the pH value of filtrate a. When the pH value of filtrate a reaches 7, stop introducing ammonia gas. Then, transfer filtrate a to an evaporating dish and carry out heating and evaporation treatment until the liquid is completely evaporated to obtain light yellow crystal a.

[0030] Step 3: Add methanol to the light yellow crystal a obtained in Step 2, with a solid-liquid ratio of 1:5. Heat it to 50 °C and keep stirring for 1 hour. Subsequently, carry out pressure filtration using a filter press to obtain filtrate b and filter residue b. Filter residue b is 1.18 Kg of white crystal. After being detected by XRD (X-ray diffraction), the peak positions are consistent with the main peak positions of the ammonium molybdate standard PDF card. Through ICP-MS testing, the molybdenum content is 47.56%. After calculation, the purity of the obtained ammonium molybdate is 97%, and the recovery rate of molybdenum is 97%.

[0031] Transfer filtrate b to an evaporating dish and carry out heating and evaporation treatment until the liquid is completely evaporated to obtain 0.487 Kg of white crystal C. This white crystal C is detected by XRD (X-ray diffraction), and its peak positions are consistent with the main peak positions of the ammonium perrhenate standard PDF card. Through ICP-MS testing, the rhenium content is 66.63%. After calculation, the purity of the obtained ammonium perrhenate is 96%, and the recovery rate of rhenium is 95%.

[0032] Example 3

[0033] A method for recycling rhenium-molybdenum alloy waste. The rhenium-molybdenum alloy waste is defective products in the production process of a certain molybdenum company. The molybdenum content in the rhenium-molybdenum alloy waste is 70%, and the rhenium content is 25%. The method includes the following steps:

[0034] Step 1: Take 1 Kg of rhenium-molybdenum alloy waste. After crushing, put it into a ball mill and ball mill for 30 minutes, then screen it using a 50-mesh sieve. The oversize material is returned to the ball mill for continuous ball milling, and the undersize material is put into a corundum crucible. Then, add analytical pure concentrated sulfuric acid into the crucible, and set the solid-liquid ratio to 1:4. Cover the crucible lid, put it into a muffle furnace, and carry out sulfation roasting at a temperature of 400 °C for 60 minutes. After roasting is completed, wait for the product to cool to room temperature, grind it to 200 mesh, and then add deionized water. The volume ratio of the material to deionized water is 5:1. Subsequently, heat it to 90 °C and keep stirring for 2 hours, then carry out pressure filtration using a filter press to obtain filtrate a and filter residue a. Filter residue a needs to be returned to the sulfation roasting process for reprocessing.

[0035] Step 2: Carry out ammoniation treatment on filtrate a obtained in Step 1. Introduce ammonia gas and stir, while monitoring the pH value of filtrate a. When the pH value of filtrate a reaches 7, stop introducing ammonia gas. Then, transfer filtrate a to an evaporating dish and carry out heating evaporation treatment until the liquid is completely evaporated to obtain light yellow crystal a.

[0036] Step 3: Add ethanol to the light yellow crystal a obtained in Step 2, with a solid-liquid ratio of 1:5. Heat it to 50 °C and keep stirring for 1 hour. Subsequently, carry out pressure filtration using a filter press to obtain filtrate b and filter residue b. Filter residue b is 134.42 Kg of white crystal. After XRD (X-ray diffraction) detection, the peak positions are consistent with the main peak positions of the ammonium molybdate standard PDF card. Through ICP-MS testing, the molybdenum content is 48.95%. After calculation, the purity of the obtained ammonium molybdate is 95%, and the recovery rate of molybdenum is 94%.

[0037] Transfer filtrate b to an evaporating dish and carry out heating evaporation treatment until the liquid is completely evaporated to obtain 0.35 Kg of white crystal C. This white crystal C is detected by XRD (X-ray diffraction), and its peak positions are consistent with the main peak positions of the ammonium perrhenate standard PDF card. Through ICP-MS testing, the rhenium content is 67.32%. After calculation, the purity of the obtained ammonium perrhenate is 97%, and the recovery rate of rhenium is 98%.

[0038] Example 4

[0039] A method for recycling rhenium-molybdenum alloy waste. The rhenium-molybdenum alloy waste is a defective product in the production process of a certain molybdenum company. The molybdenum content in the rhenium-molybdenum alloy waste is 65%, and the rhenium content is 35%. The method includes the following steps:

[0040] Step 1: Take 1 Kg of rhenium-molybdenum alloy waste. After crushing, put it into a ball mill and ball mill for 30 minutes, then screen it using a 50-mesh sieve. The oversize material is returned to the ball mill for continuous ball milling, and the undersize material is put into a corundum crucible. Then, add analytical pure concentrated sulfuric acid into the crucible, and set the solid-liquid ratio to 1:4. Cover the crucible lid, put it into a muffle furnace, and carry out sulfation roasting at a temperature of 400 °C for 60 minutes. After roasting is completed, wait for the product to cool to room temperature, grind it to 200 mesh, and then add deionized water. The volume ratio of the material to deionized water is 5:1. Subsequently, heat it to 90 °C and keep stirring for 2 hours, and then carry out pressure filtration using a filter press to obtain filtrate a and filter residue a. Filter residue a needs to be returned to the sulfation roasting process for reprocessing.

[0041] Step 2: Ammoniate the filtrate a obtained in Step 1, introduce ammonia gas and stir, and at the same time monitor the pH value of filtrate a. When the pH value of filtrate a reaches 7, stop introducing ammonia gas. Then, transfer filtrate a to an evaporating dish and carry out heating evaporation until the liquid completely evaporates to obtain white crystal a.

[0042] Step 3: Add methanol to the pale yellow crystal a obtained in Step 2, with a solid-liquid ratio of 1:5, heat to 50 °C and keep stirring for 1 hour. Subsequently, carry out pressure filtration using a filter press to obtain filtrate b and filter residue b. Filter residue b is 1.251 Kg of white crystal. After being detected by XRD (X-ray diffraction), the peak positions are consistent with the main peak positions of the ammonium molybdate standard PDF card. Through ICP-MS testing, the molybdenum content is 45.03%. After calculation, the purity of the obtained ammonium molybdate is 92%, and the recovery rate of molybdenum is 94%.

[0043] Transfer filtrate b to an evaporating dish and carry out heating evaporation until the liquid completely evaporates to obtain 0.525 Kg of white crystal C. This white crystal C is detected by XRD (X-ray diffraction), and its peak positions are consistent with the main peak positions of the ammonium perrhenate standard PDF card. Through ICP-MS testing, the rhenium content is 65.23%. After calculation, the purity of the obtained ammonium perrhenate is 94%, and the recovery rate of rhenium is 98%.

[0044] The product yield and analysis results are shown in Table 1.

[0045] Table 1 Product Yield and Analysis Results Table

[0046]

[0047] From the data in Table 1, it can be concluded that Examples 1-4 adopt the method provided by the present invention for recycling rhenium-molybdenum alloy waste. The purity of the obtained ammonium molybdate is 97%, and the recovery rate of molybdenum is 97%; the purity of the obtained ammonium perrhenate is 97%, and the recovery rate of rhenium is 98%. Compared with the prior art, the recovery rate is significantly improved.

[0048] The above are only the preferred embodiments of the present invention.

Claims

1. A method for recovering molybdenum-rhenium alloy waste, characterized in that: The following steps are involved: Step 1: Crushing, weighing the waste containing molybdenum-rhenium alloy, and then crushing the waste; Step 2: Ball milling. After the waste is crushed, it is put into the ball mill for ball milling for 30 minutes. After the ball milling is completed, it is sieved with a 50-mesh screen to obtain the sieve-surface material and the sieve-underface material. The sieve-surface material needs to be returned to the ball mill for further ball milling. Step 3: Sulfate roasting: the sieve material obtained in step 2 is placed in a corundum crucible, and analytical pure concentrated sulfuric acid is added to the crucible, with a solid-liquid ratio of 1:

4. Then, the crucible is covered and placed in a muffle furnace for roasting at a temperature range of 400°C to 800°C for 60 to 90 minutes. After the roasting is completed, the product is cooled to room temperature. Step 4: water immersion filter press treatment, after the product of step 3 is ground to 200 mesh, deionized water is added, and the volume ratio of the material to the deionized water is 5:

1. Subsequently, it is heated to 90°C and stirred for 2 hours, and then a filter press is used to perform filter press treatment to obtain filtrate a and filter residue a. The filter residue a needs to be returned to the sulfation roasting process of step 3 for further treatment. Step 5: ammoniation treatment, evaporation crystallization: The filtrate a obtained in step 1 is subjected to ammoniation treatment, ammonia gas is introduced and stirred, and the pH value of the filtrate a is monitored at the same time. When the pH value of the filtrate a reaches 7, the introduction of ammonia gas is stopped. Then, the filtrate a is transferred to an evaporating dish and heated and evaporated until the liquid is completely evaporated to obtain light yellow crystals a. Step 6: dissolving with organic solvent, filtering and evaporating: add the light yellow crystal a obtained in step 5 to methanol or ethanol, set the solid-liquid ratio to 1:5, heat to 50°C and keep stirring for 1 hour, then use a filter press to filter to obtain filtrate b and filter residue b. The filter residue b is white crystals. The peak position of the crystal is consistent with the main peak position of the standard PDF card of ammonium molybdate by XRD (X-ray diffraction). The molybdenum content is 44.42% to 47.56% by ICP-MS test. The purity of the obtained ammonium molybdate is The purity of the obtained ammonium perrhenate is 95% to 97%, and the recovery rate of rhenium is 93% to 98%.

Images