Method of digesting, settling and separating tungsten-based samples and detection method for tungsten-based samples

Abstract

The invention discloses a method of digesting, settling and separating tungsten-based samples and a detection method for tungsten-based samples. The method of digesting, settling and separating tungsten-based samples comprises the following steps: putting a tungsten-based sample in a container, adding water and nitric acid into the container, keeping the container airtight, carrying out microwavedigestion and settlement-separation on the sample under gradient temperatures, and restarting microwave for rinsing and deposition after the temperature of the solution decreases and is close to the boiling point of water so as to obtain a sample solution for detection and precipitates of tungstic acid. The detection method for tungsten-based samples in the invention is to analyze the digested sample solution with at least one analytical method selected from the group consisting of inductively coupled plasma mass spectrometry, inductively coupled plasma atomic emission spectrometry, flame atomic absorption spectrometry, graphite oven atomic absorption spectrometry and spectrophotometry so as to obtain the content of elements in the tungsten-based sample.

Description

technical field

[0001] The invention relates to a method for digestion and sedimentation separation of tungsten-based samples and a detection method for tungsten-based samples. Specifically, the present invention relates to a method for digesting tungsten-based samples by using microwave and nitric acid under high-pressure airtight conditions and a method for detecting the digested solution. Background technique

[0002] Metal tungsten and its alloys are one of the most important functional materials in modern industry, national defense and high-tech applications. They are used in many fields such as aerospace, atomic energy, marine automobiles, electronics, petrochemicals, metal processing, equipment manufacturing and military industries. widely. Tungsten is mainly used to produce hard alloys and ferrotungsten, which can be used to manufacture knives, automobile crankshaft cylinders, gas turbines, radiation protection shields, electron tubes, metal surface hardening materi...

Examples

preparation example Construction

[0018] The method of preparing a sample solution according to an embodiment of the present invention uses only nitric acid. More specifically, the method for preparing a sample solution according to an embodiment of the present invention is implemented in the existing HF-HNO 3 On the basis of the open digestion system of the electric heating plate, the use of hydrofluoric acid, the most critical sample digestion reagent in the original method, is abandoned, and a series of unfavorable factors caused by the introduction of hydrofluoric acid are avoided, such as corrosion of instruments, inability to use for the determination of element Si, and inaccurate test results. Accurate etc.

[0019] Due to the introduction of microwave technology, the present invention realizes rapid and complete digestion of samples such as tungsten carbide, metal tungsten, and hard alloy by only adding nitric acid under high-pressure airtightness and specific control parameters, and completely oxidize...

Embodiment 1

[0033] Digestion and sedimentation separation of metallic tungsten samples

[0034] Weigh 0.1000g tungsten powder sample (FWI-I, W>99.9%, produced by Zhuzhou Cemented Carbide Factory) (hereinafter referred to as sample No. 1) in the inner tank of microwave digestion, firstly along the wall of the inner tank to wash accurately Add 15.0mL of water quantitatively, and rinse all the samples that may be attached to the tank wall, and then add 4.0mL of concentrated nitric acid. Then put the outer jar on, close the lid and tighten it with a torque wrench to ensure a good seal. Put the sealed outer tank into the microwave digestion furnace according to the operation steps of the instrument, and connect the temperature and pressure sensors. Perform microwave digestion according to the set microwave digestion heating program. This embodiment adopts the microwave reaction method with three step steps to ramp up the temperature. The pressure is controlled below 800psi (1psi=6.895KPa). ...

Embodiment 2

[0039] The sample to be digested is 0.5000g tungsten powder sample (FWI-I, W>99.9%, produced by Zhuzhou Cemented Carbide Factory) (hereinafter referred to as No. 2 sample), add 25.0mL water and 10.0mL concentrated nitric acid, microwave program: 5min Raise the temperature to 190°C and hold it for 12 minutes; raise the temperature to 220°C for 2 minutes and hold it for 3 minutes; cool the solution to 105°C, restart the microwave for 1 minute and raise the temperature to 125°C and hold it for 5 minutes. Besides, the metal tungsten sample was digested in the same manner as in Example 1, and the supernatant was detected by ICP-AES.

technical field

[0001] The invention relates to a method for digestion and sedimentation separation of tungsten-based samples and a detection method for tungsten-based samples. Specifically, the present invention relates to a method for digesting tungsten-based samples by using microwave and nitric acid under high-pressure airtight conditions and a method for detecting the digested solution. Background technique

[0002] Metal tungsten and its alloys are one of the most important functional materials in modern industry, national defense and high-tech applications. They are used in many fields such as aerospace, atomic energy, marine automobiles, electronics, petrochemicals, metal processing, equipment manufacturing and military industries. widely. Tungsten is mainly used to produce hard alloys and ferrotungsten, which can be used to manufacture knives, automobile crankshaft cylinders, gas turbines, radiation protection shields, electron tubes, metal surface hardening materi...

Examples

preparation example Construction

[0018] The method of preparing a sample solution according to an embodiment of the present invention uses only nitric acid. More specifically, the method for preparing a sample solution according to an embodiment of the present invention is implemented in the existing HF-HNO 3 On the basis of the open digestion system of the electric heating plate, the use of hydrofluoric acid, the most critical sample digestion reagent in the original method, is abandoned, and a series of unfavorable factors caused by the introduction of hydrofluoric acid are avoided, such as corrosion of instruments, inability to use for the determination of element Si, and inaccurate test results. Accurate etc.

[0019] Due to the introduction of microwave technology, the present invention realizes rapid and complete digestion of samples such as tungsten carbide, metal tungsten, and hard alloy by only adding nitric acid under high-pressure airtightness and specific control parameters, and completely oxidize...

Embodiment 1

[0033] Digestion and sedimentation separation of metallic tungsten samples

[0034] Weigh 0.1000g tungsten powder sample (FWI-I, W>99.9%, produced by Zhuzhou Cemented Carbide Factory) (hereinafter referred to as sample No. 1) in the inner tank of microwave digestion, firstly along the wall of the inner tank to wash accurately Add 15.0mL of water quantitatively, and rinse all the samples that may be attached to the tank wall, and then add 4.0mL of concentrated nitric acid. Then put the outer jar on, close the lid and tighten it with a torque wrench to ensure a good seal. Put the sealed outer tank into the microwave digestion furnace according to the operation steps of the instrument, and connect the temperature and pressure sensors. Perform microwave digestion according to the set microwave digestion heating program. This embodiment adopts the microwave reaction method with three step steps to ramp up the temperature. The pressure is controlled below 800psi (1psi=6.895KPa). ...

Embodiment 2

[0039] The sample to be digested is 0.5000g tungsten powder sample (FWI-I, W>99.9%, produced by Zhuzhou Cemented Carbide Factory) (hereinafter referred to as No. 2 sample), add 25.0mL water and 10.0mL concentrated nitric acid, microwave program: 5min Raise the temperature to 190°C and hold it for 12 minutes; raise the temperature to 220°C for 2 minutes and hold it for 3 minutes; cool the solution to 105°C, restart the microwave for 1 minute and raise the temperature to 125°C and hold it for 5 minutes. Besides, the metal tungsten sample was digested in the same manner as in Example 1, and the supernatant was detected by ICP-AES.

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