阅读说明：本技术 去除高纯锑表面污染物的方法 (Method for removing high-purity antimony surface pollutants ) 是由 狄聚青 朱刘 刘运连 李镇宏 于 2020-12-04 设计创作，主要内容包括：本公开提供一种去除高纯锑表面污染物的方法,其包括步骤：步骤一：装料,将高纯锑和盐装入坩埚中,盐不与锑反应、盐的熔点低于锑的熔点、盐的密度低于锑的密度且溶于水；步骤二：升温熔料,在使锑不与氧接触的条件下,升温熔化高纯锑和盐后降温,高纯锑和盐凝固且高纯锑先于盐凝固；步骤三：清洗阶段,在坩埚中取出凝固在一起的盐和高纯锑,用纯水将凝固的盐洗掉；步骤四：烘干阶段,在真空条件下将步骤三获得的高纯锑烘干。本公开得到的高纯锑表面光亮、无污染物。(The present disclosure provides a method for removing contaminants from a surface of high purity antimony, comprising the steps of: the method comprises the following steps: charging, namely charging high-purity antimony and salt into a crucible, wherein the salt does not react with the antimony, the melting point of the salt is lower than that of the antimony, and the density of the salt is lower than that of the antimony and is dissolved in water; step two: heating and melting the material, namely heating and melting the high-purity antimony and the salt under the condition that the antimony is not in contact with oxygen, and then cooling, wherein the high-purity antimony and the salt are solidified, and the high-purity antimony is solidified before the salt; step three: in the cleaning stage, salt and high-purity antimony which are solidified together are taken out of the crucible, and the solidified salt is washed away by pure water; step four: and a drying stage, drying the high-purity antimony obtained in the step three under a vacuum condition. The high-purity antimony obtained by the method has a bright surface and is free of pollutants.)

1. A method for removing high-purity antimony surface pollutants, which comprise gallium oxide and carbon powder, is characterized by comprising the following steps:

the method comprises the following steps: charging, namely charging high-purity antimony and salt into a crucible, wherein the salt does not react with the antimony, the melting point of the salt is lower than that of the antimony, and the density of the salt is lower than that of the antimony and is dissolved in water;

step two: heating and melting the material, namely heating and melting the high-purity antimony and the salt under the condition that the antimony is not in contact with oxygen, and then cooling, wherein the high-purity antimony and the salt are solidified, and the high-purity antimony is solidified before the salt;

step three: in the cleaning stage, salt and high-purity antimony which are solidified together are taken out of the crucible, and the solidified salt is washed away by pure water;

step four: and a drying stage, drying the high-purity antimony obtained in the step three under a vacuum condition.

2. The method for removing surface contaminants of high-purity antimony according to claim 1, wherein in the first step, the crucible used is a quartz crucible.

3. The method for removing surface contaminants of high-purity antimony according to claim 1, wherein in the step one, the salt is one selected from the group consisting of lithium chloride, a mixed salt of lithium chloride and sodium chloride, a mixed salt of lithium chloride and potassium chloride, sodium chloride, potassium chloride and a mixed salt of lithium chloride.

4. The method for removing surface contaminants of high-purity antimony according to claim 1, wherein in step two, the temperature is reduced to room temperature.

5. The method for removing surface contaminants of high-purity antimony according to claim 1, wherein in the second step, the condition for not contacting antimony with oxygen is an inert atmosphere, a reducing atmosphere or a vacuum condition.

6. The method for removing surface contaminants of high-purity antimony according to claim 1, wherein in the second step, the thickness of the molten salt is 5mm to 10mm, and the volume of the salt is 5mm to 10mm multiplied by the area of the opening of the crucible.

7. The method for removing surface contaminants of high-purity antimony according to claim 1, wherein in the second step, the temperature-raising melting stage raises the temperature to a maximum temperature of 640 ℃ to 650 ℃.

8. The method for removing the surface pollutants of the high-purity antimony according to claim 1, wherein in the third step, the cleaning mode is ultrasonic cleaning.

9. The method for removing contaminants from a surface of high purity antimony according to claim 1, wherein in step three, the pure water is washed until the conductivity of the water is the same as the conductivity before washing.

10. The method for removing surface contaminants of high-purity antimony according to claim 1, wherein in the fourth step, the drying temperature under vacuum is 60 ℃ to 80 ℃.

Technical Field

The invention relates to the field of purification, in particular to a method for removing pollutants on the surface of high-purity antimony.

Background

Antimony is a silvery white shiny hard and brittle metal, 60% of which is used to produce flame retardants, and 20% of which is used to make alloying materials, sliding bearings and welding agents in batteries. The use of antimony in the semiconductor industry is constantly evolving, mainly as a dopant in ultra-high conductivity n-type silicon wafers, which are used for the production of diodes, infrared detectors and hall effect elements. Indium antimonide and gallium antimonide are materials used for making mid-infrared detectors.

In the preparation process of the high-purity antimony, oxide and carbon powder exist on the surface, and the pollutants are difficult to remove. In semiconductor applications, contamination of the surface of high purity antimony can affect the performance of devices made therewith. Therefore, there is a need to provide a method for removing contaminants from the surface of high purity antimony.

Disclosure of Invention

In view of the problems in the background art, it is an object of the present disclosure to provide a method for removing surface contaminants of high purity antimony, which can obtain high purity antimony with bright surface and without contaminants.

In order to achieve the above object, the present disclosure provides a method for removing surface contaminants of high-purity antimony, the surface contaminants of high-purity antimony including gallium oxide and carbon powder, comprising the steps of: the method comprises the following steps: charging, namely charging high-purity antimony and salt into a crucible, wherein the salt does not react with the antimony, the melting point of the salt is lower than that of the antimony, and the density of the salt is lower than that of the antimony and is dissolved in water; step two: heating and melting the material, namely heating and melting the high-purity antimony and the salt under the condition that the antimony is not in contact with oxygen, and then cooling, wherein the high-purity antimony and the salt are solidified, and the high-purity antimony is solidified before the salt; step three: in the cleaning stage, salt and high-purity antimony which are solidified together are taken out of the crucible, and the solidified salt is washed away by pure water; step four: and a drying stage, drying the high-purity antimony obtained in the step three under a vacuum condition.

In some embodiments, in step one, the crucible used is a quartz crucible.

In some embodiments, in step one, the salt is one selected from the group consisting of lithium chloride, a mixed salt of lithium chloride and sodium chloride, a mixed salt of lithium chloride and potassium chloride, sodium chloride, potassium chloride, and a mixed salt of lithium chloride.

In some embodiments, in step two, the temperature is reduced to room temperature.

In some embodiments, in step two, the conditions under which the antimony is not contacted with oxygen are an inert atmosphere, a reducing atmosphere, or vacuum conditions.

In some embodiments, in the second step, the thickness of the molten salt is 5mm to 10mm, and the volume of the salt is 5mm to 10mm multiplied by the area of the opening of the crucible.

In some embodiments, in the second step, the melting stage is heated to a maximum temperature of 640 ℃ to 650 ℃.

In some embodiments, in step three, the cleaning manner is ultrasonic cleaning.

In some embodiments, in step three, the pure water is washed until the conductivity of the water is the same as the conductivity before washing.

In some embodiments, in step four, the drying temperature under vacuum is 60 ℃ to 80 ℃.

The beneficial effects of this disclosure are as follows:

in the method for removing the pollutants on the surface of the high-purity antimony, the flow is short, the method is simple, and the surface of the prepared high-purity antimony is clean, bright and free of pollutants.

Detailed Description

The method for removing surface contaminants of high-purity antimony according to the present disclosure is described in detail below.

The method for removing the surface pollutants of the high-purity antimony comprises the following steps: the method comprises the following steps: charging, namely charging high-purity antimony and salt into a crucible, wherein the salt does not react with the antimony, the melting point of the salt is lower than that of the antimony, and the density of the salt is lower than that of the antimony and is dissolved in water; step two: heating and melting the material, namely heating and melting the high-purity antimony and the salt under the condition that the antimony is not in contact with oxygen, and then cooling, wherein the high-purity antimony and the salt are solidified, and the high-purity antimony is solidified before the salt; step three: in the cleaning stage, salt and high-purity antimony which are solidified together are taken out of the crucible, and the solidified salt is washed away by pure water; step four: and a drying stage, drying the high-purity antimony obtained in the step three under a vacuum condition.

In some embodiments, in step one, the crucible used is a quartz crucible. The quartz crucible has smooth surface, can well infiltrate salt melt, and can not pollute high-purity antimony.

In step one, the salt used does not react with antimony. If the salt reacts with antimony, secondary contamination of the antimony will result.

In some embodiments, in step one, the salt is one selected from the group consisting of lithium chloride, a mixed salt of lithium chloride and sodium chloride, a mixed salt of lithium chloride and potassium chloride, sodium chloride, potassium chloride, and a mixed salt of lithium chloride. The melting point of the salt is lower than that of antimony, wherein the melting points of the mixed salt or the single salt (namely lithium chloride) are lower than that of high-purity antimony, oxygen is not contained, the mixed salt or the single salt does not react with the high-purity antimony, the wetting effect is good, the price is low, and the mixed salt or the single salt is the best choice for removing impurities. If the melting point of the salt is too high, the salt is solidified before the high-purity antimony melt is solidified, and a surface salt layer is cracked when the high-purity antimony is solidified, so that the high-purity antimony is contacted with the atmosphere, and secondary pollution is easily caused.

In step one, the salt has a density lower than that of antimony and is soluble in water. After the high-purity antimony and the salt are melted, the salt is covered on the high-purity antimony due to low density, pollutants such as gallium oxide or carbon powder on the surface of the high-purity antimony can float on the salt, and after the temperature is reduced, the high-purity antimony is sealed under the sealing of the salt, so that secondary pollution can not occur due to contact with oxygen. The pollutants on the surface of the high-purity antimony are solidified along with the salt, so that the removal effect is achieved.

In some embodiments, in the second step, the temperature is decreased to room temperature, in other words, after the temperature is decreased to room temperature, the third step is performed to take out the solidified high-purity antimony and salt. The metallic antimony can still be oxidized if contacting with oxygen at high temperature, so that the solidified metallic antimony and the salt are taken out from the crucible after the temperature is reduced to room temperature, and the secondary pollution of the metallic antimony is avoided.

In some embodiments, in step two, the conditions under which the antimony is not contacted with oxygen are an inert atmosphere, a reducing atmosphere, or vacuum conditions. The inert gas, reducing atmosphere or vacuum can avoid the oxidation of the high-purity antimony by contacting with oxygen in the melting process and the solidification process.

In some embodiments, in step two, the thickness of the salt after melting is 5mm to 10 mm. When the thickness of the molten salt is less than 5mm, the high-purity antimony cannot be completely covered when the salt is solidified, so that the high-purity antimony is in contact with the atmosphere, and secondary pollution is easily caused; when the thickness of the molten salt is more than 10mm, the waste of the salt is caused, and the cost is increased.

In some embodiments, the volume of salt is the crucible opening area multiplied by 5mm to 10mm, in other words the volume of salt is equal to the crucible opening area multiplied by the thickness of the salt after melting. The volume of salt added is related to the size of the crucible, but it is ensured that the thickness of the salt melt is 5mm to 10mm, i.e. the volume of salt should be 5mm to 10mm multiplied by the open area of the crucible.

In some embodiments, in the second step, the melting stage is heated to a maximum temperature of 640 ℃ to 650 ℃. The temperature is too low, so that the high-purity antimony cannot be completely melted, and the effect of removing surface pollutants is influenced; the excessive temperature leads to serious volatilization of antimony and salt, and influences the yield.

In some embodiments, in the third step, the cleaning mode is ultrasonic cleaning, and the cavitation action, the acceleration action and the direct current action of the ultrasonic waves in the liquid are utilized to directly and indirectly act on the liquid and the dirt, so that the dirt layer is dispersed, emulsified and stripped to achieve the purpose of cleaning, and the ultrasonic waves have high frequency and short wavelength, so that the propagation directionality is good, the penetration capability is strong, and the cleaning effect is good.

In some embodiments, in step three, the salt is washed away with pure water. The salt is dissolved in water, and the salt water does not pollute the high-purity antimony and can effectively remove the salt. And the pollutants in the salt enter the pure water to achieve the effect of separating the high-purity antimony.

In some embodiments, in step three, the pure water is washed until the conductivity of the water is the same as the conductivity before washing. The pure water ultrasonic cleaning can fully clean the salt attached to the high-purity antimony until the conductivity of the water after cleaning is consistent with that before cleaning, which indicates that the salt is completely cleaned.

In some embodiments, in the fourth step, the drying temperature under vacuum is 60-80 ℃. The secondary oxidation of the high-purity antimony can be avoided by drying under vacuum.

Finally, the test procedure is given

Example 1

The method comprises the following steps: high purity antimony and sodium chloride and lithium chloride in a molar ratio of 1:1 were charged into a quartz crucible.

Step two: the thickness of the molten salt is 5mm, and the temperature is raised to 650 ℃ under the inert atmosphere to melt the salt and the antimony, and then the temperature is reduced.

Step three: and then taking out the high-purity antimony, and ultrasonically cleaning the pure water until the conductivity of the cleaned water is the same as that before cleaning.

Step four: drying at 80 deg.C under vacuum.

The high-purity antimony obtained in the example has a bright surface and is free of pollutants.

Example 2

The method comprises the following steps: high-purity antimony and lithium chloride and potassium chloride in a molar ratio of 1:1 were charged into a quartz crucible.

Step two: the thickness of the molten salt was 10 mm. The temperature is raised to 650 ℃ under vacuum, the salt and the antimony are melted, and then the temperature is reduced.

Step three: and then taking out the high-purity antimony, and ultrasonically cleaning the pure water until the conductivity of the cleaned water is the same as that before cleaning.

Step four: drying at 60 deg.C under vacuum.

The high-purity antimony obtained in the example has a bright surface and is free of pollutants.

Comparative example 1

In step one, only potassium chloride is used as the salt, and the rest is the same as in example 1.

Raising the temperature to 650 ℃ in an inert atmosphere, melting antimony, floating potassium chloride on the antimony liquid level without melting antimony, and achieving the effect of removing oxide impurities.

Comparative example 2

In step one, sodium chloride is used as the salt only, and the rest is the same as in example 1

Raising the temperature to 650 ℃ under the inert atmosphere, melting antimony, floating sodium chloride on the antimony liquid level without melting, and achieving the effect of removing oxide impurities.

Comparative example 3

The salt in the first step is a mixed salt of sodium chloride and potassium chloride, and the rest is the same as in example 1.

Raising the temperature to 650 ℃ in an inert atmosphere, melting antimony, floating the mixed salt of sodium chloride and potassium chloride on the antimony liquid level without melting the mixed salt, and achieving the effect of removing oxide impurities.

Analysis of the results in examples 1-2 and comparative examples 1-3 revealed that: when the melting point of the selected salt is lower than that of antimony, the obtained high-purity antimony has a bright surface and no pollutants.

The above-disclosed features are not intended to limit the scope of practice of the present disclosure, and therefore, all equivalent variations that are described in the claims of the present disclosure are intended to be included within the scope of the claims of the present disclosure.