A method for recovering tungsten and boric acid from tungsten powder XRF test tablet samples

Abstract

The present invention belongs to the technical field of resource recycling, and specifically relates to a method for recovering tungsten and boric acid from a tungsten powder XRF detection tablet sample, wherein the tungsten powder XRF detection tablet sample is placed in an oven for heating; the heated XRF detection tablet sample is placed in a ball mill for crushing to obtain powder; the powder is placed in a classifier for airflow classification to obtain powder 1 and powder 2. The present invention realizes the separation and recovery of tungsten and boric acid in the tungsten powder XRF detection tablet sample through a simple processing flow without the need to add any additional chemical reagents, and the purity of the obtained tungsten powder is ≥99.25%, and the purity of the boric acid crystal is ≥99.35%.

Description

Technical Field

[0001] The invention belongs to the technical field of resource recycling, and specifically relates to a method for recovering tungsten and boric acid from a tungsten powder XRF test tablet sample. Background Art

[0002] In the process of tungsten powder production, XRF (X Ray Fluorescence) is often used to detect impurity elements in samples. There are two main methods for preparing powder samples for XRF testing: tableting and melting. Compared with the melting method, the tableting method is widely used because of its simple and fast operation, low analysis cost, and no pollution to the environment. In the sample preparation process, boric acid is generally used as a binder to pad the bottom and edge, and pressed into samples under a certain pressure for testing and analysis. With the large increase in the amount of testing, a large number of XRF test tablet samples will be generated every year. However, such samples are directly treated as solid waste, which not only causes a waste of resources but also increases operating costs. Summary of the invention

[0003] In order to solve the problems existing in the prior art, the main purpose of the present invention is to provide a method for recovering tungsten and boric acid from a tungsten powder XRF test pellet sample.

[0004] To solve the above technical problems, according to one aspect of the present invention, the present invention provides the following technical solutions:

[0005] A method for recovering tungsten and boric acid from a tungsten powder XRF test pellet sample comprises the following steps:

[0006] S1. Place the tungsten powder XRF test pellet sample in an oven for heating;

[0007] S2, placing the heated XRF test tablet sample in a ball mill to crush it into powder;

[0008] S3. The powder is placed in a classifier for airflow classification to obtain powder 1 and powder 2.

[0009] As a preferred embodiment of the method for recovering tungsten and boric acid from tungsten powder XRF test pellet samples described in the present invention, wherein: in the step S1, the heating temperature is 100-130°C and the heating time is 4-8h.

[0010] As a preferred embodiment of the method for recovering tungsten and boric acid from tungsten powder XRF test tablet samples described in the present invention, wherein: in the step S2, the ball-to-material ratio is (3-5):1, the ball milling speed is 220-300 r / min, and the ball milling time is 60-90 min.

[0011] As a preferred embodiment of the method for recovering tungsten and boric acid from tungsten powder XRF test tablet samples described in the present invention, wherein: in the step S3, the classifying wheel speed of the classifier is 5150-5300 rpm, the carrier gas pressure of the classifier is 0.43-0.59 MPa, and the feed rate of the classifier is 6.5-7.5 kg / h.

[0012] As a preferred embodiment of the method for recovering tungsten and boric acid from tungsten powder XRF test tablet samples described in the present invention, wherein: in the step S3, the powder 1 is placed in a funnel with filter paper, washed with hot water, and then placed in a drying oven to dry to obtain tungsten powder.

[0013] As a preferred embodiment of the method for recovering tungsten and boric acid from tungsten powder XRF test tablet samples described in the present invention, wherein: in the step S3, the hot water temperature is 50-70°C, the amount of hot water used per unit weight of powder 1 is 2.5-5L / kg, and the hot water flow rate is 1000-1500mL / min.

[0014] As a preferred embodiment of the method for recovering tungsten and boric acid from tungsten powder XRF test pellet samples described in the present invention, wherein: in the step S3, the water after washing the powder 1 is introduced into the container containing the powder 2, so that the powder 2 is dissolved in the water to obtain a boron-containing solution, and the solution is evaporated and dried to prepare boric acid crystals, and water is recovered by condensation.

[0015] As a preferred embodiment of the method for recovering tungsten and boric acid from tungsten powder XRF test pellet samples described in the present invention, wherein: in step S3, the evaporation drying temperature is 60-80°C.

[0016] As a preferred embodiment of the method for recovering tungsten and boric acid from a tungsten powder XRF test pellet sample described in the present invention, wherein: in the step S3, after washing, the tungsten powder is dried in a drying oven to obtain a purity of ≥99.25%.

[0017] As a preferred embodiment of the method for recovering tungsten and boric acid from tungsten powder XRF test tablet samples described in the present invention, wherein: in step S3, the purity of the boric acid crystals is ≥99.35%, and no characteristic peaks of other phases appear in the XRD diagram of the boric acid crystals.

[0018] The beneficial effects of the present invention are as follows:

[0019] The present invention provides a method for recovering tungsten and boric acid from a tungsten powder XRF detection tablet sample, wherein the tungsten powder XRF detection tablet sample is placed in an oven for heating; the heated XRF detection tablet sample is placed in a ball mill for crushing to obtain powder; the powder is placed in a classifier for airflow classification to obtain powder 1 and powder 2. The present invention realizes the separation and recovery of tungsten and boric acid in the tungsten powder XRF detection tablet sample through a simple processing flow without the need to add any additional chemical reagents, and the purity of the obtained tungsten powder is ≥99.25%, and the purity of the boric acid crystal is ≥99.35%. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0021] Figure 1 This is the XRD pattern of the tungsten powder obtained in Example 1 of the present invention;

[0022] Figure 2 This is the XRD diagram of the boric acid crystals obtained in Example 1 of the present invention.

[0023] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0024] The following will be described clearly and completely in conjunction with the technical solutions in the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] According to one aspect of the present invention, the present invention provides the following technical solution:

[0026] A method for recovering tungsten and boric acid from a tungsten powder XRF test pellet sample comprises the following steps:

[0027] S1. Place the tungsten powder XRF test pellet sample in an oven for heating;

[0028] S2, placing the heated XRF test tablet sample in a ball mill to crush it into powder;

[0029] S3. The powder is placed in a classifier for airflow classification to obtain powder 1 and powder 2.

[0030] The present invention heats the tungsten powder XRF detection tablet sample. During the heating process, boric acid is transformed from relatively viscous boric acid to brittle metaboric acid, which is beneficial to ball milling and crushing of boric acid and tungsten powder. Meanwhile, by utilizing the large difference in powder density after ball milling, a physical classification method is adopted to skillfully separate the tungsten powder and metaboric acid. After the metaboric acid is dissolved, evaporated and dried, boric acid crystals are obtained. The present invention realizes the separation and recovery of tungsten and boric acid in the tungsten powder XRF detection tablet sample without the need to add any additional chemical reagents, and water in the treatment process can be recycled, thereby saving water resources.

[0031] Preferably, in step S1, the heating temperature is 100-130°C, and the heating time is 4-8h. Specifically, the heating temperature may be, for example, any one of 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, or any range between two thereof, and the heating time may be, for example, any one of 4h, 5h, 6h, 7h, 8h, or any range between two thereof.

[0032] Preferably, in step S2, the ball-to-material ratio is (3-5):1, the ball milling speed is 220-300 r / min, and the ball milling time is 60-90 min. Specifically, the ball-to-material ratio can be, for example, any one of 3:1, 3.5:1, 4:1, 4.5:1, 5:1, or a range between any two thereof, the ball milling speed can be, for example, any one of 220 r / min, 230 r / min, 240 r / min, 250 r / min, 260 r / min, 270 r / min, 280 r / min, 290 r / min, or 300 r / min, or a range between any two thereof, and the ball milling time can be, for example, any one of 60 min, 70 min, 80 min, or 90 min, or a range between any two thereof.

[0033] Preferably, in step S3, the classifying wheel speed of the classifier is 5150-5300rpm, the classifier carrier gas pressure is 0.43-0.59MPa, and the classifier feed rate is 6.5-7.5kg / h. Specifically, the classifying wheel speed of the classifier can be, for example, any one of 5150rpm, 5200rpm, 5250rpm, 5300rpm, or any range between two of them, the classifier carrier gas pressure can be, for example, any one of 0.43MPa, 0.45MPa, 0.50MPa, 0.55MPa, 0.59MPa, or any range between two of them, and the classifier feed rate can be, for example, any one of 6.5kg / h, 6.8kg / h, 7.0kg / h, 7.2kg / h, 7.5kg / h, or any range between two of them.

[0034] Preferably, in step S3, the powder 1 is placed in a funnel with filter paper, washed with hot water, and then placed in a drying oven for drying to obtain tungsten powder.

[0035] Preferably, in step S3, the hot water temperature is 50-70°C, the amount of hot water used per unit weight of the powder 1 is 2.5-5 L / kg, and the hot water flow rate is 1000-1500 mL / min. Specifically, the hot water temperature can be, for example, any one of 50°C, 55°C, 60°C, 65°C, and 70°C, or any range between two of them, the amount of hot water used per unit weight of the powder 1 is any one of 2.5 L / kg, 3.0 L / kg, 3.5 L / kg, 4.0 L / kg, 4.5 L / kg, and 5.0 L / kg, or any range between two of them, and the hot water flow rate can be, for example, any one of 1000 mL / min, 1100 mL / min, 1200 mL / min, 1300 mL / min, 1400 mL / min, and 1500 mL / min, or any range between two of them.

[0036] Preferably, in step S3, the water after washing the powder 1 is introduced into a container containing the powder 2, so that the powder 2 is dissolved in the water to obtain a boron-containing solution, and evaporated and dried to prepare boric acid crystals, and water is recovered by condensation. The powder 2 is metaboric acid, and the boron-containing solution is a mixture of boric acid and metaboric acid.

[0037] Preferably, in step S3, the evaporation drying temperature is 60-80° C. At this temperature, the solution can be evaporated to dryness without causing the decomposition of boric acid. Specifically, the evaporation drying temperature can be, for example, any one of 60° C., 65° C., 70° C., 75° C., 80° C., or a range between any two thereof.

[0038] Preferably, in step S3, the purity of the tungsten powder obtained by washing and drying in a drying oven is ≥99.25%.

[0039] Preferably, in step S3, the purity of the boric acid crystals is ≥99.35%, and no characteristic peaks of other phases appear in the XRD diagram of the boric acid crystals.

[0040] The technical solution of the present invention is further described below in conjunction with specific embodiments.

[0041] Example 1

[0042] A method for recovering tungsten and boric acid from a tungsten powder XRF test pellet sample comprises the following steps:

[0043] S1. Place the tungsten powder XRF test pellet sample in an oven for heating; the heating temperature is 105°C and the heating time is 8h;

[0044] S2. The heated XRF test tablet sample is placed in a ball mill for crushing to obtain powder; the ball-to-material ratio is 5:1, the ball mill speed is 300 r / min, and the ball milling time is 90 min;

[0045] S3. Place the powder in a classifier for airflow classification. The classifier wheel speed is 5300rpm, the classifier carrier gas pressure is 0.59MPa, and the classifier feed rate is 7.5kg / h; obtain powder 1 and powder 2. Place powder 1 in a funnel with filter paper and wash with hot water. The water temperature is 70°C. The amount of water used per unit weight of powder 1 is 5L / kg, and the water flow rate is 1500mL / min. After washing, place it in a drying oven to dry to obtain tungsten powder; introduce the water after washing powder 1 into a container containing powder 2, so that powder 2 is dissolved in water to obtain a boron-containing solution, and evaporate and dry it. The evaporation and drying temperature is 70°C to prepare boric acid crystals, and at the same time recover water by condensation. After washing, place it in a drying oven to dry to obtain tungsten powder (its XRD pattern is as shown below). Figure 1 The purity of the boric acid crystal is 99.65%. Figure 2 As shown, the purity of the boric acid crystals is 99.72%, and no characteristic peaks of other phases appear.

[0046] Example 2

[0047] A method for recovering tungsten and boric acid from a tungsten powder XRF test pellet sample comprises the following steps:

[0048] S1. Place the tungsten powder XRF test pellet sample in an oven for heating; the heating temperature is 120°C and the heating time is 4h;

[0049] S2. The heated XRF test tablet sample is placed in a ball mill for crushing to obtain powder; the ball-to-material ratio is 3:1, the ball mill speed is 220r / min, and the ball milling time is 60min;

[0050] S3, the powder is placed in a classifier for airflow classification, the classifier wheel speed is 5150rpm, the classifier carrier gas pressure is 0.45MPa, and the classifier feed rate is 6.5kg / h; powder 1 and powder 2 are obtained. Powder 1 is placed in a funnel with filter paper, washed with hot water, the water temperature is 60℃, the amount of water used per unit weight of powder 1 is 2.5L / kg, the water flow rate is 1000mL / min, and after washing, it is placed in a drying oven to dry to obtain tungsten powder; the water after washing powder 1 is introduced into a container containing powder 2, so that powder 2 is dissolved in water to obtain a boron-containing solution, and evaporated and dried, the evaporation and drying temperature is 80℃, boric acid crystals are prepared, and water is recovered by condensation. After washing, the purity of the tungsten powder obtained by drying in a drying oven is 99.26%. The purity of the boric acid crystals is 99.53%, and no characteristic peaks of other phases appear in the boric acid crystals.

[0051] Example 3

[0052] A method for recovering tungsten and boric acid from a tungsten powder XRF test pellet sample comprises the following steps:

[0053] S1. Place the tungsten powder XRF test pellet sample in an oven for heating; the heating temperature is 130°C and the heating time is 6 hours;

[0054] S2. The heated XRF test tablet sample is placed in a ball mill for crushing to obtain powder; the ball-to-material ratio is 4:1, the ball mill speed is 250r / min, and the ball milling time is 70min;

[0055] S3, the powder is placed in a classifier for airflow classification, the classifier wheel speed is 5200rpm, the classifier carrier gas pressure is 0.50MPa, and the classifier feed rate is 7.0kg / h; powder 1 and powder 2 are obtained. Powder 1 is placed in a funnel with filter paper, washed with hot water, the water temperature is 55°C, the amount of water used per unit weight of powder 1 is 3L / kg, the water flow rate is 1300mL / min, and after washing, it is placed in a drying oven to dry to obtain tungsten powder; the water after washing powder 1 is introduced into a container containing powder 2, so that powder 2 is dissolved in water to obtain a boron-containing solution, and evaporated and dried, the evaporation and drying temperature is 60°C, boric acid crystals are prepared, and water is recovered by condensation. After washing, the purity of the tungsten powder obtained by drying in a drying oven is 99.41%. The purity of the boric acid crystals is 99.36%, and no characteristic peaks of other phases appear in the boric acid crystals.

[0056] Comparative Example 1

[0057] The difference from Embodiment 1 is that step S1 is not performed.

[0058] It is difficult to separate tungsten from boric acid in this comparative example.

[0059] Comparative Example 2

[0060] The difference from Example 1 is that step S3 is not performed, and water-soluble separation is directly performed.

[0061] This comparative example consumes a lot of water and the purity of the product is not high. The purity of the recovered tungsten powder is 45.15%, and the purity of the boric acid crystal is 43.72%.

[0062] Comparative Example 3

[0063] The difference from Example 1 is that in step S3, the rotating speed of the classifying wheel of the classifier is 2500 rpm, the carrier gas pressure of the classifier is 0.25 MPa, and the feed rate of the classifier is 4.0 kg / h.

[0064] The classification process parameters of this comparative example are not suitable, and the purity of the obtained tungsten powder is 60.69%, and the purity of the boric acid crystal is 63.12%.

[0065] It can be seen from the above embodiments and comparative examples that the present invention places the tungsten powder XRF detection tablet sample in an oven for heating; places the heated XRF detection tablet sample in a ball mill for crushing to obtain powder; and places the powder in a classifier for airflow classification to obtain powder 1 and powder 2. The present invention achieves separation and recovery of tungsten and boric acid in the tungsten powder XRF detection tablet sample through a simple processing flow without the need to add any additional chemical reagents, and the purity of the obtained tungsten powder is ≥99.25%, and the purity of the boric acid crystal is ≥99.35%.

[0066] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for recovering tungsten and boric acid from tungsten powder XRF test tablet samples, characterized in that: The steps include: S1. Place the tungsten powder XRF test pellet sample in an oven for heating; S2, placing the heated XRF test tablet sample in a ball mill to crush it into powder; S3, placing the powder in a classifier for airflow classification to obtain powder 1 and powder 2; the classifier wheel speed is 5150-5300rpm, the classifier carrier gas pressure is 0.43-0.59MPa, and the classifier feed rate is 6.5-7.5kg / h; Powder 1 is placed in a funnel with filter paper, washed with hot water, and then dried in a drying oven to obtain tungsten powder; The water after washing the powder 1 is introduced into the container containing the powder 2, so that the powder 2 is dissolved in the water to obtain a boron-containing solution, which is evaporated and dried to prepare boric acid crystals, and water is recovered by condensation.

2. The method for recovering tungsten and boric acid from tungsten powder XRF test pellet samples according to claim 1, characterized in that: In the step S1, the heating temperature is 100-130° C. and the heating time is 4-8 hours.

3. The method for recovering tungsten and boric acid from tungsten powder XRF test pellet samples according to claim 1, characterized in that: In the step S2, the ball-to-material ratio is (3-5):1, the ball milling speed is 220-300 r / min, and the ball milling time is 60-90 min.

4. The method for recovering tungsten and boric acid from tungsten powder XRF test pellet samples according to claim 1, characterized in that: In step S3, the hot water temperature is 50-70° C., the amount of hot water used per unit weight of the powder 1 is 2.5-5 L / kg, and the hot water flow rate is 1000-1500 mL / min.

5. The method for recovering tungsten and boric acid from tungsten powder XRF test pellet samples according to claim 1, characterized in that: In step S3, the evaporation drying temperature is 60-80°C.

6. The method for recovering tungsten and boric acid from tungsten powder XRF test pellet samples according to claim 1, characterized in that: In the step S3, after washing, the tungsten powder is placed in a drying oven and dried to obtain a tungsten powder with a purity of ≥99.25%.

7. The method for recovering tungsten and boric acid from tungsten powder XRF test pellet samples according to claim 1, characterized in that: In step S3, the purity of the boric acid crystals is ≥99.35%.

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