Method for short process preparation of tungsten oxide from tungsten-containing waste material

Abstract

The present application relates to the technical field of industrial solid waste recycling, and discloses a method for preparing tungsten oxide from tungsten-containing waste materials through a short process, which comprises the following steps: pretreating the tungsten-containing waste materials through roasting, then stirring and leaching the pretreated materials with an acid solution and an oxidizing agent, separating the liquid from the solid after leaching, obtaining tungstic acid solid-phase residue and cobalt salt solution, and obtaining tungsten oxide after calcining the tungstic acid solid-phase residue. The present application uses the combined treatment technology of low-temperature roasting pretreatment and oxidizing acid leaching to directly convert tungsten carbide, tungsten, tungsten oxide and other tungsten-containing phases into tungstic acid solid phase in an aqueous solution system, and acid-soluble non-tungsten components such as cobalt and iron into solution. The tungsten recovery rate of the tungsten-containing waste materials in the present application is as high as 95% or more. The present application has the advantages of a short process, simple operation, high efficiency, no pollution, common reagents, low reagent consumption, low cost, and suitability for industrial production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of industrial solid waste recycling, in particular to a method for preparing tungsten oxide from tungsten-containing waste materials. BACKGROUND

[0002] With the increase of tungsten ore consumption, the amount of tungsten-containing waste materials also increases. In recent years, many countries have treated cemented carbide waste materials as a valuable second resource to solve the problem of raw material shortage and reduce the production cost of cemented carbide. Therefore, how to recycle and utilize these tungsten-containing waste materials in an environmentally friendly and efficient manner has become an important issue for the sustainable development of the tungsten industry. The recycling and recovery of tungsten and cobalt resources are of great practical significance for the development of the national economy.

[0003] Currently, there are two main types of methods for recycling and recovering tungsten-containing waste materials: one type is to first convert tungsten carbide into tungsten oxide through oxidation, and then convert the tungsten oxide into tungstate (sodium tungstate, ammonium tungstate, etc.) through alkaline dissolution, such as nitre melting, sodium sulfate smelting, calcination and alkaline leaching, in-situ oxidation and reduction carbonization, etc. The process is then recycled back to the traditional production process of carbon tungsten, impurities are removed, APT is extracted, and carbon tungsten is prepared through reduction carbonization. This type of method has the characteristics of long process flow, high cost of raw and auxiliary materials, high production cost, high waste water generation, and low recovery rate. The other type is to dissolve the binder phase (cobalt) and directly obtain carbon tungsten powder, such as acid leaching, zinc melting, and electrochemical dissolution. Although this type of method has a short process flow, it has the problems of insufficient purity of carbon tungsten powder, generation of pollutants, and substandard performance of recycled cemented carbide.

[0004] Tungsten oxide material can be used as an industrial raw material to produce ammonium paratungstate, tungsten powder, and high-purity tungsten carbide. In various recycling processes for treating tungsten-containing waste materials, it is necessary to convert tungsten carbide and / or tungsten in the waste materials into tungsten oxide. For example, patent CN106673064A discloses a method for producing ammonium paratungstate from cemented carbide grinding material, which includes: first, adding water to the cemented carbide grinding material to form a slurry, and then adding the slurry into a reaction kettle for acid leaching to separate tungsten and cobalt; the obtained tungsten carbide residue is oxidized and calcined at a temperature of 600-1000℃ for 3-10h to obtain tungsten oxide material; the tungsten oxide material is mixed with an alkali and heated to obtain an alkali leaching solution; the alkali leaching solution is purified through ion exchange and impurity removal to obtain a purified ammonium tungstate solution; and ammonium paratungstate is obtained by evaporating and crystallizing the purified ammonium tungstate solution. However, this method has the problems of long production cycle, high energy consumption, and high production cost.

[0005] In recent years, domestic and foreign researchers have developed some new methods for short process preparation of tungsten oxide from tungsten-containing waste materials. For example, patent CN114525408A discloses a method for joint treatment of waste lithium cobalt oxide positive electrode material and tungsten-containing solid waste. The method utilizes the strong oxidizing property of lithium cobalt oxide under acidic conditions to directly oxidize and transform tungsten and / or tungsten carbide into tungsten oxide during the metal separation process in an aqueous medium. However, this method uses expensive raw and auxiliary materials, has high production cost, and is prone to bring in impurities during the recovery process.

[0006] In addition, there is a nitric acid mixed acid leaching method, such as patents CN115305364A and CN115386733A, which use phosphorus-nitric mixed acid and nitric-sulfur mixed acid, respectively, to decompose and recover tungsten-containing waste materials. The tungsten-containing waste materials are directly converted into tungsten acid in the mixed acid, and then the tungsten acid is calcined to obtain tungsten oxide products. Although this method has the advantages of short process flow and simple operation, it produces a large amount of nitrogen oxides during the nitric acid leaching process, which seriously pollutes the environment, and the impurity content in the product is high, which increases the subsequent purification load.

[0007] In view of the above problems existing in the existing tungsten-containing waste material regeneration and recovery process technology, it is urgent to develop a method for short process preparation of tungsten oxide from tungsten-containing waste materials, which is short in process flow, low in cost, simple and efficient, and clean in production, so as to achieve the purpose of efficient utilization of solid waste resources. SUMMARY

[0008] (I) Technical problems solved

[0009] In view of the shortcomings of the prior art, the purpose of the present application is to provide a method for short process preparation of tungsten oxide from tungsten-containing waste materials, which solves the problems of complex operation, long process flow, high cost, poor recovery effect and many other problems in the existing technical methods.

[0010] (II) Technical solutions

[0011] To achieve the above-mentioned purpose, the present application provides the following technical solutions. A method for short process preparation of tungsten oxide from tungsten-containing waste materials, comprising the following steps:

[0012] S1: roasting pretreatment of tungsten-containing waste material to obtain activated tungsten-containing waste material;

[0013] S2: mixing the activated tungsten-containing waste material obtained in S1 with an acidic solution and an oxidizing agent to obtain a solid-liquid mixture by stirring;

[0014] S3: stirring and leaching the solid-liquid mixture obtained in S2 at a certain temperature for a period of time, then performing liquid-solid separation, and then washing the filter residue with hot water for 3-5 times to obtain tungsten acid solid residue and cobalt salt solution.

[0015] S4: calcining the tungstic acid solid phase residue obtained in S3 to obtain tungsten oxide product.

[0016] As a preferred solution, the tungsten-containing waste material in step S1 is derived from floor material, dust collection material, grinding material, unsintered waste blank and waste material generated in the production process of hard alloy, as well as floor material, dust collection material, waste material powder tungsten-containing waste material in the production process of tungsten carbide powder and tungsten powder; the tungsten-containing waste material mainly comprises: tungsten mass content of 30% to 95%, cobalt mass content of 2% to 20%, and also contains a small amount of other impurity elements Fe, Cu, C, Cr, SiO2, Ni and V.

[0017] As a preferred solution, the roasting pretreatment in step S1 is aerobic roasting, which is exposed to air or oxygen is introduced for roasting, the roasting temperature is 100 to 300℃, and the roasting time is 1 to 5h.

[0018] As a preferred solution, the acid solution in step S2 is selected from at least one of sulfuric acid and hydrochloric acid, the mass concentration of the acid solution is 50 to 300g / L, and the acid solution is added in an amount of 5 to 20:1 mL / g according to the liquid-solid ratio (liquid volume to solid mass ratio) of the activated tungsten-containing waste material.

[0019] As a preferred solution, the oxidizing agent in step S2 is selected from at least one of hydrogen peroxide, manganese dioxide, sodium chlorate or potassium permanganate, and the amount of the oxidizing agent is 0.1 to 1 times the mass of the activated tungsten-containing waste material.

[0020] As a preferred solution, the stirring leaching of the solid-liquid mixture in step S3 is carried out under the conditions of reaction temperature of 30 to 100℃ and holding time of 1 to 8h.

[0021] As a preferred solution, the stirring rate of the stirring leaching of the solid-liquid mixture in step S3 is 100 to 500rpm.

[0022] As a preferred solution, the cobalt salt solution in step S3 is purified by chemical precipitation method, and ammonium oxalate is used to precipitate cobalt to prepare cobalt oxalate product, or the cobalt oxalate is calcined to produce cobalt oxide powder product.

[0023] As a preferred solution, the tungstic acid solid phase residue in step S4 is calcined at a temperature of 400 to 800℃ for 1 to 6h.

[0024] As a preferred solution, the tungstic acid solid phase residue of the step S3 is calcined to directly prepare a tungsten oxide product; or the tungstic acid solid phase residue or the tungsten oxide is dissolved into an ammonium tungstate solution by using ammonia water, and an ammonium paratungstate product is prepared after evaporation and crystallization; or the tungstic acid solid phase residue or the tungsten oxide is dissolved into a sodium tungstate solution by using alkali leaching, and an ammonium tungstate solution is obtained by using an ion exchange process or an extraction process, and an ammonium paratungstate product is obtained by evaporation and crystallization of the ammonium tungstate solution.

[0025] (Three) beneficial effects

[0026] Compared with the prior art, the beneficial effects achieved by the present application are:

[0027] 1. The present application uses the combined treatment technology of low-temperature roasting pretreatment and oxidative acid leaching to directly convert tungsten carbide, tungsten, tungsten oxide and other tungsten-containing substances in the activated tungsten-containing waste in the aqueous solution system into tungstic acid solid phase, and the non-tungsten components such as cobalt and iron in the tungsten-containing waste have strong solubility in the oxidative acid leaching system and are converted into the liquid phase, realizing short-process and efficient separation of tungsten and impurities such as cobalt and iron, and greatly reducing the process flow and production cost.

[0028] 2. The present application includes a low-temperature roasting pretreatment process, which can not only remove oil stains from the tungsten-containing waste, but also can realize preliminary oxidation and activation treatment of tungsten, cobalt, iron and other components in the tungsten-containing waste, reducing the consumption of oxidants in the subsequent acid leaching process; at the same time, the structure of the tungsten-containing waste becomes more loose and porous, which is beneficial to the subsequent oxidative acid leaching.

[0029] 3. The oxidant used in the present application is widely available, cheap and easy to obtain, and the problems of nitrogen oxide pollution, large acid consumption and large consumption of oxidant nitric acid in the nitric acid mixed acid method are avoided; the process of the present application is simple and reasonable, basically no waste water, waste gas and waste residue are produced, the reagents used are common reagents on the market, the consumption of auxiliary materials is small and the cost is low, and the present application is suitable for industrial production.

[0030] 4. By calcining the tungstic acid solid phase residue, the present application can realize short-process preparation of tungsten oxide product from tungsten-containing waste, solving the problems of complex operation, long process flow, high cost and poor recovery effect in the existing technical methods. The method provided by the present application can make the tungsten recovery rate of the tungsten-containing waste reach more than 95%. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 It is a process flow diagram of the method of the present application;

[0032] Figure 2 It is an XRD analysis result diagram of the tungstic acid solid phase residue obtained in Example 1 of the present application;

[0033] Figure 3 It is an XRD analysis result diagram of the tungsten oxide product obtained after calcination in Example 1 of the present application. DETAILED DESCRIPTION

[0034] In order to more clearly understand the objects, technical solutions and advantages of the present application, the present application will be further described below, but the protection scope of the present application will not be limited in the following examples, the following examples are only used to specifically describe the present application, and do not limit the scope of the present application in any way. In the following examples, the instruments and equipment involved are conventional instruments and equipment unless otherwise specified; the raw materials involved are conventional commercial industrial raw materials unless otherwise specified; the processing and manufacturing methods involved are conventional methods unless otherwise specified. It should be understood that these descriptions are only exemplary and do not limit the scope of the present application. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present application.

[0035] In order to solve the problems of complex separation method, long process flow, low recovery rate, high equipment requirement, difficult cobalt-tungsten separation, serious pollution, high energy consumption and other problems in various tungsten-containing waste regeneration treatment technologies in the prior art, a method for preparing tungsten oxide from tungsten-containing waste by short process is provided, please refer to Figure 1 , the method comprises the following steps:

[0036] S1: roasting pretreatment of tungsten-containing waste to obtain activated tungsten-containing waste.

[0037] Further, in the embodiments of the present application, the tungsten-containing waste is derived from floor material, dust collection material, grinding material, unsintered waste blank and waste material generated in the hard alloy production process, as well as floor material, dust collection material, waste material powder tungsten-containing waste generated in the tungsten carbide powder and tungsten powder production process; the main components in the tungsten-containing waste are: tungsten mass content of 30%~95%, cobalt mass content of 2%~20%, and also containing a small amount of other impurity elements Fe, Cu, C, Cr, SiO2, Ni and V. It should be noted that the above substance and element content is only to meet the need of full disclosure, and does not constitute a limitation on the scheme itself, the method provided by the present application is suitable for tungsten-containing waste obtained by commercial and existing processing methods. In addition, the present application does not have special limitation on the source of tungsten-containing waste, which can be obtained by commercial purchase, or according to the existing waste generated in the hard alloy production process. The inventors found that the finer the particle size of the tungsten-containing waste, the larger the contact area with the solution, and the easier the oxidation and acid leaching conversion reaction with the acid solution and oxidizing agent.

[0038] Further, in the embodiments of the present application, the roasting pretreatment is carried out by oxygen roasting, which is exposed to air or roasting by introducing oxygen.

[0039] Further, in the embodiments of the present application, the roasting pretreatment is carried out at a temperature of 100-300℃ for 1-5h. The low-temperature roasting can remove oil stains and low-temperature volatiles, and achieve the preliminary oxidation of various components in the tungsten-containing waste material. Meanwhile, the structure of the tungsten-containing waste material becomes more loose and porous, which is beneficial to the subsequent oxidation acid leaching. The inventors have found that the above-mentioned roasting temperature and roasting time can ensure the complete activation and conversion of the tungsten-containing waste material.

[0040] S2: mixing the activated tungsten-containing waste material obtained in S1 with an acidic solution and an oxidizing agent to obtain a solid-liquid mixture.

[0041] Further, in the embodiments of the present application, the acidic solution is selected from at least one of sulfuric acid and hydrochloric acid, and the mass concentration of the acidic solution is 50-300g / L. The higher the concentration of the acidic solution, the faster the reaction speed, which is more conducive to the separation of tungsten and cobalt in the activated tungsten-containing waste material.

[0042] Further, in the embodiments of the present application, the acidic solution is added in an amount of 5-20:1 mL / g in terms of the liquid-solid ratio (ratio of liquid volume to solid mass) of the activated tungsten-containing waste material. Further, the liquid-solid ratio is preferably 12-18:1. The larger the liquid-solid ratio, the better the leaching effect, which can significantly improve the recovery rate of cobalt and tungsten.

[0043] Further, in the embodiments of the present application, the oxidizing agent is selected from at least one of hydrogen peroxide, manganese dioxide, sodium chlorate or potassium permanganate, and the amount of the oxidizing agent is 0.1-1 times the mass of the activated tungsten-containing waste material. The inventors have found that the increase of the amount of the oxidizing agent can significantly improve the reaction effect of converting various tungsten-containing phases in the activated tungsten-containing waste material into tungstic acid. If the amount of the oxidizing agent is smaller, the activated tungsten-containing waste material needs to be oxidized and leached for a longer time.

[0044] S3: stirring and leaching the solid-liquid mixture obtained in S2 at a certain temperature for a period of time, then performing liquid-solid separation, and then washing the filter residue with hot water for 3-5 times to obtain tungstic acid solid residue and a cobalt salt solution.

[0045] Further, in the embodiments of the present application, the stirring and leaching of the solid-liquid mixture is carried out at a reaction temperature of 30-100℃ and a holding time of 1-8h.

[0046] Further, in the embodiments of the present application, the stirring and leaching of the solid-liquid mixture is carried out at a stirring rate of 100-500rpm. The inventors have found that the above-mentioned stirring speed can accelerate the conversion reaction effect of the activated tungsten-containing waste material.

[0047] Further, in the embodiments of the present application, the technical principle of activating tungsten-containing waste material by oxidizing acid leaching is to use the strong oxidizing property of oxidizing agent in an acidic solution to oxidize tungsten carbide, tungsten and tungsten oxide in the tungsten-containing waste material into tungstic acid solid phase slag; and to dissolve cobalt and iron components in the waste material into the solution; and to realize high-efficiency separation of tungsten, cobalt and iron components through filtering and washing in a short process. Taking the technical scheme of activating tungsten-containing waste material by oxidizing acid leaching in a sulfuric acid system with manganese dioxide and hydrogen peroxide as oxidizing agents as an example, the main chemical reaction equations are shown as follows:

[0048] WC+Co+H2O2+2H2SO4+MnO2+2O2(g)=H2WO4+CoSO4+MnSO4+CO2(g)+2H2O;

[0049] W+Co+H2O2+2H2SO4+MnO2+O2(g)=H2WO4+CoSO4+MnSO4+2H2O;

[0050] 2WO3+Co+2H2O2+2H2SO4+MnO2=2H2WO4+CoSO4+MnSO4+2H2O+O2(g);

[0051] Further, the traditional single acid leaching process is not enough to oxidize tungsten carbide and / or tungsten in the tungsten-containing waste material, and can only dissolve cobalt and iron components. However, by using the method of the present application, the tungsten carbide and / or tungsten can be oxidized to tungstic acid on the basis of the activated tungsten-containing waste material obtained through roasting pretreatment and then adding an oxidizing agent for oxidizing acid leaching.

[0052] Further, in the embodiments of the present application, the liquid-solid separation method is any technology that can realize liquid-solid separation in the prior art, such as plate and frame filter pressing and filtering, which will not be described here.

[0053] Further, in the embodiments of the present application, the filter residue is washed with hot water for 3 to 5 times, so as to make the soluble cobalt salt in the tungstic acid solid phase slag enter the liquid phase through multiple washing, and improve the purity of the tungstic acid solid phase slag and the tungsten recovery rate.

[0054] Further, in the embodiments of the present application, the cobalt salt solution is purified and impurities are removed by chemical precipitation, and then ammonium oxalate is used to precipitate cobalt to prepare cobalt oxalate products or the cobalt oxalate is calcined to produce cobalt oxide powder products.

[0055] S4: calcining the tungstic acid solid phase slag obtained in S3 to obtain a tungsten oxide product.

[0056] Further, in the embodiments of the present application, the calcination temperature of the tungstic acid solid phase slag is 400 to 800 DEG C. The inventor finds that the above calcination temperature can accelerate the complete conversion of tungstic acid.

[0057] Further, in the embodiment of the present application, the tungstic acid solid phase residue is calcined to directly prepare WO3, and the reaction equation is shown as follows:

[0058] H2WO4= WO3+ H2O(g) ;

[0059] Further, in the embodiment of the present application, the calcination time of the tungstic acid solid phase residue is 1-6 h. The inventors find that the above-mentioned calcination time can ensure the complete decomposition and conversion of tungstic acid.

[0060] Further, the tungstic acid solid phase residue is calcined to directly prepare the tungsten oxide product in the step S3; or the tungsten oxide product is prepared by dissolving the tungstic acid solid phase residue or the tungsten oxide into ammonium tungstate solution using ammonia water, and then evaporating and crystallizing to obtain ammonium paratungstate product; or the tungsten oxide product is prepared by dissolving the tungstic acid solid phase residue or the tungsten oxide into sodium tungstate solution using alkali leaching, and then obtaining ammonium tungstate solution by ion exchange process or extraction process, and then evaporating and crystallizing the ammonium tungstate solution to obtain ammonium paratungstate product.

[0061] The present application will be described in detail with reference to specific embodiments, and it should be noted that these embodiments are merely illustrative and do not limit the present application in any way.

[0062] Example 1

[0063] A method for preparing tungsten oxide from tungsten-containing waste material in a short process, and the steps are as follows:

[0064] 200 g of powdery tungsten-containing waste material with a tungsten content of 76.5% and a cobalt mass content of 9.3% is weighed and placed in a muffle furnace for calcination at 300°C for 2 h to obtain active tungsten-containing waste material; a sulfuric acid solution with a mass concentration of 200 g / L is added to the active tungsten-containing waste material, and the liquid-solid ratio is controlled to be 10:1, and hydrogen peroxide with a mass ratio of 0.5 times that of the active tungsten-containing waste material and manganese dioxide with a mass ratio of 0.3 times that of the active tungsten-containing waste material are added respectively; the stirring leaching conditions of the active tungsten-containing waste material oxidation acid leaching are as follows: reaction temperature 80°C, holding time 3 h, and stirring rate 400 rpm; after the leaching is completed, the liquid and solid are separated, and the filter residue is washed with hot water for 5 times; the obtained filter residue is calcined at 500°C for 3 h to obtain a tungsten oxide product.

[0065] As shown in the XRD analysis results in the attached Figure 2 and attached Figure 3 graphs, the XRD analysis results confirm that the obtained filter residue is the spectrum of tungstic acid, and the filter residue is completely converted into WO3 after calcination; the tungsten recovery rate of the tungsten-containing waste material is as high as 97.1%, and the cobalt leaching rate is 99.2%.

[0066] Example 2

[0067] A method for preparing tungsten oxide from tungsten-containing waste material in a short process, and the steps are as follows:

[0068] Take 200 g of powder containing tungsten waste material with a tungsten content of 76.5% and a cobalt mass content of 9.3% into a muffle furnace and calcine at 200 ℃ for 3 h to obtain active tungsten-containing waste material; add a hydrochloric acid solution with a mass concentration of 120 g / L to the active tungsten-containing waste material and control the liquid-solid ratio to be 8:1, and add hydrogen peroxide with a mass ratio of 0.2 times and sodium chlorate with a mass ratio of 0.5 times of the active tungsten-containing waste material, respectively; the stirring leaching conditions of the active tungsten-containing waste material oxidation acid leaching are: reaction temperature 50 ℃, holding time 2 h, stirring speed 500 rpm; after leaching, liquid-solid separation is performed, and the filter residue is washed with hot water for 4 times; the obtained filter residue is calcined at 700 ℃ for 2 h to obtain a tungsten oxide product.

[0069] Analysis and detection: XRD analysis results confirm that the obtained filter residue is the spectrum of tungstic acid, and the filter residue after calcination is completely converted into WO3; the tungsten recovery rate in the tungsten-containing waste material is as high as 96.3%, and the cobalt leaching rate is 98.2%.

[0070] Example 3

[0071] A method for preparing tungsten oxide from tungsten-containing waste material in a short process, the steps are as follows:

[0072] Take 200 g of powder containing tungsten waste material with a tungsten content of 76.5% and a cobalt mass content of 9.3% into a muffle furnace and calcine at 200 ℃ for 3 h to obtain active tungsten-containing waste material; add a hydrochloric acid solution with a mass concentration of 120 g / L to the active tungsten-containing waste material and control the liquid-solid ratio to be 8:1, and add hydrogen peroxide with a mass ratio of 0.2 times and sodium chlorate with a mass ratio of 0.5 times of the active tungsten-containing waste material, respectively; the stirring leaching conditions of the active tungsten-containing waste material oxidation acid leaching are: reaction temperature 50 ℃, holding time 2 h, stirring speed 500 rpm; after leaching, liquid-solid separation is performed, and the filter residue is washed with hot water for 4 times; the obtained filter residue is calcined at 700 ℃ for 2 h to obtain a tungsten oxide product.

[0073] Analysis and detection: XRD analysis results confirm that the obtained filter residue is the spectrum of tungstic acid, and the filter residue after calcination is completely converted into WO3; the tungsten recovery rate in the tungsten-containing waste material is as high as 96.3%, and the cobalt leaching rate is 98.2%.

[0074] Example 4

[0075] A method for preparing tungsten oxide from tungsten-containing waste material in a short process, the steps are as follows:

[0076] Take 200 g of powder containing tungsten waste material with tungsten content of 83.9% and cobalt mass content of 7.7% into a muffle furnace and calcine at 300 ℃ for 1 h to obtain active tungsten-containing waste material; add hydrochloric acid solution with mass concentration of 50 g / L to the active tungsten-containing waste material and control the liquid-solid ratio to be 20:1, and add hydrogen peroxide with mass ratio of 1 times of the active tungsten-containing waste material; the stirring leaching conditions of the active tungsten-containing waste material oxidation acid leaching are: reaction temperature 30 ℃, holding time 6 h, stirring speed 300 rpm; after leaching, the liquid and solid are separated, and the filter residue is washed with hot water for 5 times; the obtained filter residue is calcined at 400 ℃ for 6 h to obtain tungsten oxide product.

[0077] Through analysis and detection: the XRD analysis result proves that the obtained filter residue is the spectrum of tungstic acid, and the filter residue after calcination is completely converted into WO3; the tungsten recovery rate in the tungsten-containing waste material is as high as 96.6%, and the cobalt leaching rate is 98.3%.

[0078] Example 5

[0079] A method for preparing tungsten oxide from tungsten-containing waste material in a short process, the steps are as follows:

[0080] Take 200 g of powder containing tungsten waste material with tungsten content of 83.9% and cobalt mass content of 7.7% into a tubular furnace with air and calcine at 200 ℃ for 5 h to obtain active tungsten-containing waste material; add hydrochloric acid solution with mass concentration of 160 g / L to the active tungsten-containing waste material and control the liquid-solid ratio to be 18:1, and add sodium chlorate with mass ratio of 0.1 times of the active tungsten-containing waste material; the stirring leaching conditions of the active tungsten-containing waste material oxidation acid leaching are: reaction temperature 50 ℃, holding time 3 h, stirring speed 400 rpm; after leaching, the liquid and solid are separated, and the filter residue is washed with hot water for 3 times; the obtained filter residue is calcined at 800 ℃ for 1 h to obtain tungsten oxide product.

[0081] Through analysis and detection: the XRD analysis result proves that the obtained filter residue is the spectrum of tungstic acid, and the filter residue after calcination is completely converted into WO3; the tungsten recovery rate in the tungsten-containing waste material is as high as 97.2%, and the cobalt leaching rate is 98.9%.

[0082] Example 6

[0083] A method for preparing tungsten oxide from tungsten-containing waste material in a short process, the steps are as follows:

[0084] Take 200 g of powder-like tungsten-containing waste material with a tungsten content of 83.9% and a cobalt mass content of 7.7% into a muffle furnace and calcine at 300 ℃ for 3 h to obtain active tungsten-containing waste material; add a sulfuric acid solution with a mass concentration of 300 g / L to the active tungsten-containing waste material and control the liquid-solid ratio to be 5:1, and add manganese dioxide at a mass ratio of 0.7 times that of the active tungsten-containing waste material; the stirring leaching conditions of the active tungsten-containing waste material oxidation acid leaching are as follows: reaction temperature 95 ℃, holding time 8 h, and stirring speed 400 rpm; after leaching, the liquid and solid are separated, and the filter residue is washed with hot water for 5 times; the obtained filter residue is calcined at 600 ℃ for 3 h to obtain tungsten oxide product.

[0085] Analysis and detection: XRD analysis results confirm that the obtained filter residue is the spectrum of tungstic acid, and the filter residue after calcination is completely converted into WO3; the tungsten recovery rate in the tungsten-containing waste material is as high as 98.1%, and the cobalt leaching rate is 99.2%.

[0086] Comparative Example 1

[0087] Other conditions are as in

Example 1

[0088] Analysis and detection: XRD analysis results show that there are a large amount of WC phases in the filter residue, and no tungstic acid or tungsten oxide phases are present; the cobalt leaching rate is 52.3%; that is, if no oxidant is added during the acid leaching process of the active tungsten-containing waste material, it is difficult to realize the oxidation of tungsten carbide and tungsten-containing phases, and it is also difficult to deeply acid-solubilize and separate cobalt.

[0089] Comparative Example 2

[0090] Other conditions are as in

Example 2

[0091] Analysis and detection: XRD analysis results show that there are a large amount of WC phases in the filter residue, and no tungstic acid or tungsten oxide phases are present; the cobalt leaching rate is 61.9%; that is, if the active tungsten-containing waste material is not calcined for pretreatment such as oil removal and activity modification, it is difficult to realize the oxidation and conversion of tungsten carbide, and it is also difficult to deeply acid-solubilize and separate cobalt.

[0092] The above examples are only illustrative and explanatory of the present application, and should not be interpreted as limiting the scope of protection of the present application. Any technology realized based on the above content of the present application is covered within the scope intended to be protected by the present application.

Claims

1. A method for the short process preparation of tungsten oxide from tungsten-containing scrap, characterized in that: The method comprises the following steps: S1: roasting pretreatment of tungsten-containing waste material to obtain activated tungsten-containing waste material, the roasting pretreatment of step S1 is aerobic roasting, exposure to air or roasting by oxygen, the roasting temperature is 100-300℃, and the roasting time is 1-5h; S2: mixing the activated tungsten-containing waste material obtained in S1 with an acidic solution and an oxidizing agent to obtain a solid-liquid mixture, the oxidizing agent of step S2 is selected from at least one of hydrogen peroxide, manganese dioxide, sodium chlorate or potassium permanganate, and the amount of oxidizing agent is 0.1-1 times the mass of the activated tungsten-containing waste material; S3: stirring and leaching the solid-liquid mixture obtained in S2 at a certain temperature for a period of time, then performing liquid-solid separation, and then washing the filter residue with hot water for 3-5 times to obtain tungstic acid solid residue and cobalt salt solution; S4: calcining the tungstic acid solid residue obtained in S3 to obtain tungsten oxide product.

2. A process for the preparation of tungsten oxide from tungsten-containing scrap according to claim 1, characterized in that: The tungsten-containing waste material of step S1 is derived from floor material, dust collection material, grinding material, unsintered waste blank and waste material generated in the production process of hard alloy, as well as floor material, dust collection material and waste material powder containing tungsten generated in the production process of tungsten carbide powder and tungsten powder.

3. The method of claim 1, wherein the method is characterized by: The acidic solution of step S2 is selected from at least one of sulfuric acid and hydrochloric acid, the mass concentration of the acidic solution is 50-300g / L, and the amount of the acidic solution added is 5-20:1 mL / g according to the liquid-solid ratio (liquid volume to solid mass ratio) of the activated tungsten-containing waste material.

4. The method of producing tungsten oxide from tungsten-containing scrap material in a short process according to claim 1, characterized in that: The stirring and leaching of the solid-liquid mixture of step S3 is carried out under the conditions of reaction temperature 30-100℃ and holding time 1-8h.

5. The method of producing tungsten oxide from tungsten-containing scrap material in a short process according to claim 1, characterized in that: The stirring rate of the stirring and leaching of the solid-liquid mixture of step S3 is 100-500rpm.

6. The method of producing tungsten oxide from tungsten-containing scrap material in a short process according to claim 1, characterized in that: The cobalt salt solution of step S3 is purified by chemical precipitation method, ammonium oxalate is used to precipitate cobalt to prepare cobalt oxalate product, or the cobalt oxalate is calcined to produce cobalt oxide powder product.

7. The method of producing tungsten oxide from tungsten-containing scrap material in a short process according to claim 1, characterized in that: The calcination temperature of the tungstic acid solid residue of step S4 is 400-800℃, and the calcination time is 1-6h.

8. The method of producing tungsten oxide from tungsten-containing scrap material in a short process according to claim 1, characterized in that: The tungstic acid solid residue of step S3 is directly calcined to prepare tungsten oxide product, or the tungstic acid solid residue or tungsten oxide is dissolved into ammonium tungstate solution by using ammonia water, ammonium paratungstate product is prepared after evaporation and crystallization, or the tungstic acid solid residue or tungsten oxide is dissolved into sodium tungstate solution by alkali leaching, ammonium tungstate solution is obtained by ion exchange process or extraction process, and ammonium paratungstate product is obtained by evaporation and crystallization of the ammonium tungstate solution.

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