CN109019531B - Method for preparing high-purity tellurium dioxide by taking crude tellurium as raw material - Google Patents
Method for preparing high-purity tellurium dioxide by taking crude tellurium as raw material Download PDFInfo
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- CN109019531B CN109019531B CN201810891722.9A CN201810891722A CN109019531B CN 109019531 B CN109019531 B CN 109019531B CN 201810891722 A CN201810891722 A CN 201810891722A CN 109019531 B CN109019531 B CN 109019531B
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B19/00—Selenium; Tellurium; Compounds thereof
- C01B19/004—Oxides; Hydroxides
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
Abstract
The invention provides a method for preparing high-purity tellurium dioxide by taking crude tellurium as a raw material, which effectively solves the problems of failed preparation or low purity of the high-purity tellurium dioxide caused by reaction passivation, excessively high reaction rate and the like when the high-purity tellurium dioxide is prepared by taking the crude tellurium as the raw material through a nitric acid method in the prior art by controlling reaction temperature, tellurium powder particle size, nitric acid concentration and the like, and prepares a high-purity tellurium dioxide product (more than or equal to 5N).
Description
Technical Field
The invention relates to a method for preparing high-purity tellurium dioxide by taking crude tellurium as a raw material.
Background
In recent years, with the development of advanced scientific technologies such as electronics, optics, photoelectrons and the like, the improvement of the purity of metal materials to obtain new properties has become an important direction for the development of modern material industries. To some extent, high purity metallic materials can be considered as the basis for the development of modern high and new technologies.
Tellurium is a semiconductor material, belongs to rare and scattered metals, is praised as 'vitamins of modern industry, national defense and advanced technology to create a strange bridge between people' and 'is a supporting material of a new material of the current high technology'. With the rapid development of the fields of aerospace, atomic energy, electronic industry and the like in China in recent years, the demand for high-purity rare metal materials including tellurium, tellurium dioxide, bismuth, compounds thereof and the like is increasing day by day. The method can greatly promote the development of new materials required by industries of China, such as electronic computers, communication and aerospace development, energy, medicine and health, and the like.
At present, few reports about the preparation of tellurium dioxide exist. The patent document of chinese invention patent CN101648702A discloses a method for preparing tellurium dioxide from crude tellurium, which prepares tellurium dioxide through a series of reactions of substances such as hydrogen peroxide, hydrochloric acid, sodium hydroxide, etc. How to search for a simpler tellurium dioxide preparation method on the basis of the prior art and further improve the product purity is the research direction of tellurium dioxide preparation.
Disclosure of Invention
The invention aims to provide a method for preparing high-purity tellurium dioxide by taking crude tellurium as a raw material so as to improve the production technology and product quality of tellurium dioxide.
The technical scheme of the invention is realized as follows:
a method for preparing high-purity tellurium dioxide by taking crude tellurium as a raw material comprises the following steps:
step one, cooling water is introduced to the outside of a reaction container to ensure that the reaction temperature is maintained below 40 ℃;
preparing dilute nitric acid solution from the concentrated nitric acid by using deionized water, and adding the prepared dilute nitric acid solution into a reaction vessel;
step three, crushing the crude tellurium into fine powder, slowly adding the fine powder of the crude tellurium into the dilute nitric acid solution prepared in the step two, and uniformly stirring at a low speed to ensure that the crude tellurium is completely reacted before being precipitated to the bottom of the reaction container;
step four, neutralizing the tellurium-containing solution generated in the step three by using ammonia water until the pH value is 7-8, and reacting to generate tellurium dioxide;
step five, filtering the tellurium dioxide product generated in the step four, repeatedly washing the tellurium dioxide product with pure water for not less than three times until the pH value of the washed pure water is equal to 7;
taking out the tellurium dioxide cleaned in the step five, placing the tellurium dioxide into a glass disc, paving the glass disc flat, drying the glass disc in an oven at 100 ℃, and taking out the glass disc;
step seven, putting the dried tellurium dioxide in the step six into a quartz boat, introducing high-purity oxygen into a high-temperature furnace, calcining at the temperature of 600-;
and step eight, cooling and taking out to obtain the high-purity tellurium dioxide.
Preferably, the mass fraction of the dilute nitric acid solution in the second step is 20-35%.
Preferably, the liquid-to-solid ratio of the dilute nitric acid solution to the crude tellurium is between 5 and 7.
Preferably, in the third step, the coarse tellurium is crushed to the particle size of 80-110 meshes.
Compared with the prior art, the invention has the following beneficial effects: the invention finds out the main factors influencing the reaction rate of tellurium and nitric acid, such as reaction temperature, tellurium powder particle size and nitric acid concentration; the three influencing factors are analyzed to find out the optimal reaction temperature, tellurium powder particle size and nitric acid concentration for preparing high-purity tellurium dioxide; the method for preparing the high-purity tellurium dioxide is simple, and the prepared tellurium dioxide product has high purity (more than or equal to 5N).
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Step one, cooling water is introduced to the outside of a reaction vessel to ensure that the reaction temperature is maintained below 35-40 ℃;
preparing a dilute nitric acid solution with the mass fraction of 20% by using deionized water, and adding the prepared dilute nitric acid solution into a reaction vessel;
step three, crushing the crude tellurium into fine powder with the grain size of 80 meshes, slowly adding the fine powder of the crude tellurium into the dilute nitric acid solution prepared in the step two, and uniformly stirring at a low speed to ensure that the crude tellurium completely reacts before the crude tellurium is not precipitated to the bottom of the reaction container, wherein the liquid-solid ratio of the dilute nitric acid solution to the crude tellurium is 5;
step four, neutralizing the tellurium-containing solution generated in the step three by using ammonia water until the pH value is 7-8, and reacting to generate tellurium dioxide;
step five, filtering the tellurium dioxide product generated in the step four, repeatedly washing the tellurium dioxide product with pure water for not less than three times until the pH value of the washed pure water is approximately equal to 7;
taking out the tellurium dioxide cleaned in the step five, placing the tellurium dioxide into a glass disc, paving the glass disc, drying the glass disc in an oven at the temperature of about 100 ℃, and taking out the glass disc;
step seven, putting the dried tellurium dioxide in the step six into a quartz boat, introducing high-purity oxygen into a high-temperature furnace, calcining at the temperature of 600-;
and step eight, cooling and taking out to obtain the high-purity tellurium dioxide.
Example 2
Step one, cooling water is introduced to the outside of a reaction vessel to ensure that the reaction temperature is maintained below 18-22 ℃;
preparing dilute nitric acid solution with the mass fraction of 35% by using deionized water, and adding the prepared dilute nitric acid solution into a reaction vessel;
step three, crushing the crude tellurium into fine powder with the grain size of 110 meshes, slowly adding the fine powder of the crude tellurium into the dilute nitric acid solution prepared in the step two, and uniformly stirring at a low speed to ensure that the crude tellurium completely reacts before the crude tellurium is not precipitated to the bottom of the reaction container, wherein the liquid-solid ratio of the dilute nitric acid solution to the crude tellurium is 7;
step four, neutralizing the tellurium-containing solution generated in the step three by using ammonia water until the pH value is 7-8, and reacting to generate tellurium dioxide;
step five, filtering the tellurium dioxide product generated in the step four, repeatedly washing the tellurium dioxide product with pure water for not less than three times until the pH value of the washed pure water is equal to 7;
taking out the tellurium dioxide cleaned in the step five, placing the tellurium dioxide into a glass disc, paving the glass disc, drying the glass disc in an oven at the temperature of about 100 ℃, and taking out the glass disc;
step seven, putting the dried tellurium dioxide in the step six into a quartz boat, introducing high-purity oxygen into a high-temperature furnace, calcining at the temperature of 600-;
and step eight, cooling and taking out to obtain the high-purity tellurium dioxide.
Example 3
Step one, cooling water is introduced to the outside of a reaction container to ensure that the reaction temperature is maintained below 23-27 ℃;
preparing a dilute nitric acid solution with the mass fraction of 30% by using deionized water, and adding the prepared dilute nitric acid solution into a reaction vessel;
step three, crushing the crude tellurium into fine powder with the grain size of 100 meshes, slowly adding the fine powder of the crude tellurium into the dilute nitric acid solution prepared in the step two, and uniformly stirring at a low speed to ensure that the crude tellurium completely reacts before the crude tellurium is not precipitated to the bottom of the reaction container, wherein the liquid-solid ratio of the dilute nitric acid solution to the crude tellurium is 6;
step four, neutralizing the tellurium-containing solution generated in the step three by using ammonia water until the pH value is 7-8, and reacting to generate tellurium dioxide;
step five, filtering the tellurium dioxide product generated in the step four, repeatedly washing the tellurium dioxide product with pure water for not less than three times until the pH value of the washed pure water is equal to 7;
taking out the tellurium dioxide cleaned in the step five, placing the tellurium dioxide into a glass disc, paving the glass disc, drying the glass disc in an oven at the temperature of about 100 ℃, and taking out the glass disc;
step seven, putting the dried tellurium dioxide in the step six into a quartz boat, introducing high-purity oxygen into a high-temperature furnace, calcining at the temperature of 600-;
and step eight, cooling and taking out to obtain the high-purity tellurium dioxide.
Example 4
Step one, cooling water is introduced to the outside of a reaction vessel to ensure that the reaction temperature is maintained below 28-34 ℃;
preparing dilute nitric acid solution with the mass fraction of 35% by using deionized water, and adding the prepared dilute nitric acid solution into a reaction vessel;
step three, crushing the crude tellurium into fine powder with the grain size of 110 meshes, slowly adding the fine powder of the crude tellurium into the dilute nitric acid solution prepared in the step two, and uniformly stirring at a low speed to ensure that the crude tellurium completely reacts before the crude tellurium is not precipitated to the bottom of the reaction container, wherein the liquid-solid ratio of the dilute nitric acid solution to the crude tellurium is 7;
step four, neutralizing the tellurium-containing solution generated in the step three by using ammonia water until the pH value is 7-8, and reacting to generate tellurium dioxide;
step five, filtering the tellurium dioxide product generated in the step four, repeatedly washing the tellurium dioxide product with pure water for not less than three times until the pH value of the washed pure water is equal to 7;
taking out the tellurium dioxide cleaned in the step five, placing the tellurium dioxide into a glass disc, paving the glass disc, drying the glass disc in an oven at the temperature of about 100 ℃, and taking out the glass disc;
step seven, putting the dried tellurium dioxide in the step six into a quartz boat, introducing high-purity oxygen into a high-temperature furnace, calcining at the temperature of 600-;
and step eight, cooling and taking out to obtain the high-purity tellurium dioxide.
Example 5
Step one, cooling water is introduced to the outside of a reaction vessel to ensure that the reaction temperature is maintained below 18-22 ℃;
preparing a dilute nitric acid solution with the mass fraction of 30% by using deionized water, and adding the prepared dilute nitric acid solution into a reaction vessel;
step three, crushing the crude tellurium into fine powder with the grain size of 100 meshes, slowly adding the fine powder of the crude tellurium into the dilute nitric acid solution prepared in the step two, and uniformly stirring at a low speed to ensure that the crude tellurium completely reacts before the crude tellurium is not precipitated to the bottom of the reaction container, wherein the liquid-solid ratio of the dilute nitric acid solution to the crude tellurium is 6;
step four, neutralizing the tellurium-containing solution generated in the step three by using ammonia water until the pH value is 7-8, and reacting to generate tellurium dioxide;
step five, filtering the tellurium dioxide product generated in the step four, repeatedly washing the tellurium dioxide product with pure water for not less than three times until the pH value of the washed pure water is equal to 7;
taking out the tellurium dioxide cleaned in the step five, placing the tellurium dioxide into a glass disc, paving the glass disc, drying the glass disc in an oven at the temperature of about 100 ℃, and taking out the glass disc;
step seven, putting the dried tellurium dioxide in the step six into a quartz boat, introducing high-purity oxygen into a high-temperature furnace, calcining at the temperature of 600-;
and step eight, cooling and taking out to obtain the high-purity tellurium dioxide.
Comparative example 1
The reaction temperature is maintained at about 60 ℃ in the same manner as in example 5, and the final tellurium dioxide is prepared.
Comparative example 2
The same as the method of the embodiment 5, dilute nitric acid solution with the mass fraction of 50 percent is prepared, and finally the tellurium dioxide is prepared.
Comparative example 3
The same as the method of the embodiment 5, dilute nitric acid solution with the mass fraction of 10 percent is prepared, and finally the tellurium dioxide is prepared.
Comparative example 4
The crude tellurium was pulverized into fine powder having a particle size of 60 mesh in the same manner as in example 5, to obtain tellurium dioxide.
Comparative example 5
In the same manner as in example 5, the crude tellurium was pulverized into fine powder having a particle size of 150 mesh, and finally prepared into tellurium dioxide.
| Item | Product color | Purity of the product |
| Example 1 | White colour | ≥5N |
| Example 2 | White colour | ≥5N |
| Example 3 | White colour | ≥6N |
| Example 4 | White colour | ≥6N |
| Example 5 | White colour | ≥6N |
| Comparative example 1 | Black (unqualified) | ＜6N |
| Comparative example 2 | Black (unqualified) | ＜5N |
| Comparative example 3 | White colour | ＜5N |
| Comparative example 4 | Black (unqualified) | ＜6N |
| Comparative example 5 | Black (unqualified) | ＜5N |
Analyzing the above conclusions, we found that:
the temperature is a key factor for controlling the reaction, such as overhigh system temperature, overhigh reaction speed, extremely difficult control of the process, uneven product color caused by the fact that a large amount of black passivation is covered on the surface of the tellurium powder, and incomplete reaction.
When the concentration of the nitric acid is lower than 20%, the reaction is incomplete, so that raw materials are wasted, and the product purity is insufficient; when the concentration of the nitric acid is higher than 35%, the reaction rate is too fast and difficult to control, and a large amount of black passivation is caused to cause uneven color.
Meanwhile, the tellurium powder has overlarge specific surface area due to the excessively low coarse tellurium particle size, the rate is too high when the reaction starts, and the system temperature is increased too fast, so that the passivation reaction is easily caused; the excessive grain size is easy to form compact oxide on the tellurium surface to prevent the solution from infiltrating the surface of the tellurium powder, and the nitric acid cannot react with the substances in the spherical tellurium powder; the purpose of the above measures is to control the reaction rate so that it decreases smoothly, rather than increases exponentially.
And the adopted ammonia water is neutralized to replace the existing substances such as sodium hydroxide and the like, and can be removed in a later stage by washing, heating and other modes, so that the impurity item increase of the product is reduced. And finally, calcining with high-purity oxygen to further remove elements such AS AS, S, C, N and the like in the product, and forming to further improve the product purity.
The experiment proves that the purposes of improving the preparation efficiency and the product purity of the high-purity tellurium dioxide can be achieved by reasonably controlling the reaction temperature, the tellurium powder particle size, the nitric acid concentration, the selection of a proper neutralizing reagent and other factors in the process of preparing the tellurium dioxide; the prepared product is high-purity tellurium dioxide (the product purity is more than or equal to 5N).
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (2)
1. A method for preparing high-purity tellurium dioxide by taking crude tellurium as a raw material is characterized by comprising the following steps:
step one, cooling water is introduced to the outside of a reaction container to ensure that the reaction temperature is maintained below 40 ℃;
preparing dilute nitric acid solution from the concentrated nitric acid by using deionized water, and adding the prepared dilute nitric acid solution into a reaction container, wherein the mass fraction of the dilute nitric acid solution is 20-35%;
step three, crushing the crude tellurium into fine powder with the particle size of 80-110 meshes, slowly adding the fine powder of the crude tellurium into the dilute nitric acid solution prepared in the step two, and uniformly stirring at a low speed to ensure that the crude tellurium completely reacts before the crude tellurium is not precipitated to the bottom of the reaction container;
step four, neutralizing the tellurium-containing solution generated in the step three by using ammonia water until the pH value is 7-8, and reacting to generate tellurium dioxide;
step five, filtering the tellurium dioxide product generated in the step four, repeatedly washing the tellurium dioxide product with pure water for not less than three times until the pH value of the washed pure water is equal to 7;
taking out the tellurium dioxide cleaned in the step five, placing the tellurium dioxide into a glass disc, paving the glass disc flat, drying the glass disc in an oven at 100 ℃, and taking out the glass disc;
step seven, putting the dried tellurium dioxide in the step six into a quartz boat, introducing high-purity oxygen into a high-temperature furnace, calcining at the temperature of 600-;
and step eight, cooling and taking out to obtain the high-purity tellurium dioxide.
2. The method for preparing high-purity tellurium dioxide from crude tellurium as claimed in claim 1, wherein the liquid-to-solid ratio of the dilute nitric acid solution to the crude tellurium is 5 to 7.
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| CN113501506A (en) * | 2021-08-19 | 2021-10-15 | 四川孚孚新材料科技有限公司 | High-purity tellurium dioxide and preparation method thereof |
Citations (2)
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| US4618593A (en) * | 1981-05-15 | 1986-10-21 | Nitto Chemical Industry Co., Ltd. | Process for improving activity of tellurium containing metal oxide catalysts |
| CN103397180A (en) * | 2013-08-07 | 2013-11-20 | 江西铜业股份有限公司 | Method for recovering tellurium, bismuth, antimony, and copper from complex material |
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| SU639965A1 (en) * | 1977-03-17 | 1978-12-30 | Предприятие П/Я А-7815 | Method of obtaining tellurium dioxide |
| JP3673380B2 (en) * | 1997-11-12 | 2005-07-20 | 日本電信電話株式会社 | Method for producing high purity tellurium dioxide |
| CN100544040C (en) * | 2007-04-29 | 2009-09-23 | 上海理工大学 | The treatment process of cadmium telluride material surface oxidation film |
| CN102153054A (en) * | 2011-05-03 | 2011-08-17 | 嘉兴市达泽光电技术有限公司 | Preparation method of high purity tellurium |
| CN102854178B (en) * | 2012-09-17 | 2015-05-27 | 四川鑫龙碲业科技开发有限责任公司 | Method for measuring atomic ratio of tellurium elements to cadmium elements in cadmium telluride |
| CN103803510A (en) * | 2014-02-10 | 2014-05-21 | 张家港绿能新材料科技有限公司 | Preparation method of high-purity tellurium dioxide powder |
| CN105562039B (en) * | 2016-01-31 | 2018-09-25 | 苏州大学 | A kind of telluric acid titanium photochemical catalyst, preparation method and applications |
| CN106348259A (en) * | 2016-09-13 | 2017-01-25 | 乐山凯亚达光电科技有限公司 | Preparation method of high-purity tellurium dioxide powder |
| CN107416778B (en) * | 2017-07-26 | 2020-01-21 | 广东先导稀材股份有限公司 | Method for recovering tellurium from tellurium-zinc-cadmium waste |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4618593A (en) * | 1981-05-15 | 1986-10-21 | Nitto Chemical Industry Co., Ltd. | Process for improving activity of tellurium containing metal oxide catalysts |
| CN103397180A (en) * | 2013-08-07 | 2013-11-20 | 江西铜业股份有限公司 | Method for recovering tellurium, bismuth, antimony, and copper from complex material |
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