阅读说明：本技术 一种6n级高纯碲的生产设备及生产工艺 (Production equipment and production process of 6N-grade high-purity tellurium ) 是由 俞鹰 蔡晨龙 潘荣选 钱俊杰 方支灵 戴超 申其新 于 2021-06-25 设计创作，主要内容包括：本发明公开了一种6N级高纯碲的生产设备,包括化料炉、加热炉和收集炉；所述化料炉位于加热炉的上方,并通过放料管与加热炉相连；所述加热炉通过管道与收集炉相连,所述管道位于加热炉侧为进气口,其位于收集炉侧为出气口；所述加热炉内设有高纯石英舟；所述收集炉内设有加热锥和保温区,所述保温区下方设有坩埚；所述加热锥的大部分锥体与管道处于同一水平面,其锥顶低于管道所处水平面。本结构的6N级高纯碲的生产设备,能够有效实现碲的高效提纯,同时实现连续投料连续生产,实现工业化大规模生产。本发明设备投资小,控制方便,实现连续生产的目的,延长单炉的运行时间,提升产能。(The invention discloses production equipment of 6N-grade high-purity tellurium, which comprises a material melting furnace, a heating furnace and a collecting furnace; the melting furnace is positioned above the heating furnace and is connected with the heating furnace through a discharging pipe; the heating furnace is connected with the collecting furnace through a pipeline, the pipeline is positioned on the side of the heating furnace and is provided with an air inlet, and the pipeline is positioned on the side of the collecting furnace and is provided with an air outlet; a high-purity quartz boat is arranged in the heating furnace; a heating cone and a heat preservation area are arranged in the collecting furnace, and a crucible is arranged below the heat preservation area; most of the cones of the heating cones are positioned on the same horizontal plane with the pipeline, and the cone tops of the cones are lower than the horizontal plane of the pipeline. The 6N-grade high-purity tellurium production equipment with the structure can effectively realize efficient purification of tellurium, simultaneously realize continuous feeding and continuous production, and realize industrial large-scale production. The invention has the advantages of small equipment investment, convenient control, realization of the purpose of continuous production, extension of the operation time of a single furnace and capacity improvement.)

1. A production device of 6N-grade high-purity tellurium is characterized by comprising a material melting furnace, a heating furnace and a collecting furnace; the melting furnace is positioned above the heating furnace and is connected with the heating furnace through a discharging pipe; the heating furnace is connected with the collecting furnace through a pipeline, the pipeline is positioned on the side of the heating furnace and is provided with an air inlet, and the pipeline is positioned on the side of the collecting furnace and is provided with an air outlet; a high-purity quartz boat is arranged in the heating furnace; a heating cone and a heat preservation area are arranged in the collecting furnace, and a crucible is arranged below the heat preservation area; most of the cones of the heating cones are positioned on the same horizontal plane with the pipeline, and the cone tops of the cones are lower than the horizontal plane of the pipeline.

2. The apparatus of claim 1, wherein said furnace is a horizontal tube furnace, and the chamber is a high purity quartz tube.

3. The 6N-grade high-purity tellurium production equipment as claimed in claim 1, wherein a heating resistance wire is arranged inside the heating cone, a heating resistance wire is arranged inside the heat preservation area, a heating resistance wire is arranged inside the melting furnace, and a heating resistance wire is arranged inside the heating furnace.

4. The apparatus of claim 1, wherein the heating cone and the holding section are made of hastelloy.

5. The 6N-grade high-purity tellurium production equipment according to any one of claims 1 to 4, wherein a discharge valve is arranged at the bottom of the melting furnace, and a discharge valve is arranged at the bottom of the heat preservation area.

6. A production process using the production apparatus for high purity tellurium of grade 6N as claimed in claims 1 to 5, characterized by comprising the steps of:

s1, crushing the 4N refined tellurium, and putting into a melting furnace;

s2, starting to heat the melting furnace to melt the refined tellurium into a solution;

s3, heating the heating furnace, and introducing hydrogen into the heating furnace through a pipeline;

s4, heating the temperature in the heating furnace to 600-900 ℃, controlling the hydrogen flow rate to 3-5L/min, and keeping the hydrogen flow rate stable;

s5, opening a discharge valve at the bottom of the melting furnace, and putting the melt into a high-purity quartz boat;

s6, heating the heating cone until the temperature of the rear end temperature measuring hole is kept at 380-430 ℃;

s7, stopping heating the heating furnace, taking out the high-purity quartz boat from the heating furnace after the temperature in the heating furnace is reduced to room temperature, replacing the high-purity quartz boat with a new one, and restarting production;

and S8, opening a discharge valve at the bottom of the heat preservation area, and discharging the product into the crucible for casting.

7. The process according to claim 6, wherein in S1, the 4N Te material is crushed into particles with a diameter less than 1 cm.

8. The production process of the production equipment of the 6N-grade high-purity tellurium according to the claims 6 and 7, characterized in that the temperature of the melting furnace is maintained at 470-500 ℃.

Technical Field

The invention relates to the field of production of high-purity tellurium, in particular to 6N-level high-purity tellurium production equipment and a production process for producing high-purity tellurium by using the equipment.

Background

The most obvious property of high-purity tellurium is that binary, ternary and quaternary alloys prepared by using the high-purity tellurium have good photoelectric property and thermoelectric conversion property, and can be used as alloy components of thermoelectric materials. Therefore, the material is commonly used for manufacturing solar cells, light emitting diodes and radiation detectors, and the CdTe, the HgCdTe, the PbTe, the BiTe and the like are main materials for producing solar cells, infrared detection materials, electro-optical modulators, radiation detection materials, refrigeration materials and the like. The electrical properties of the material are deteriorated due to even a very small amount of impurities. The purity of tellurium is an important factor that directly affects the properties of the material.

The preparation method of the high-purity tellurium mainly comprises a physical method and a chemical method. The chemical purification method separates tellurium from impurities through oxidation and reduction chemical reactions, has strong flexibility and large selectivity, and specifically comprises a soda powder roasting method, an alkaline high-pressure leaching method, a sulfation roasting method, an oxidation acid leaching method, a solvent extraction method, a liquid membrane method, a microbiological method, an electrolytic refining method and the like. The physical purification method is to remove impurities by means of evaporation, solidification, crystallization, diffusion and the like through a physical process, and a physical purification process consisting of multiple times of vacuum distillation and zone melting is mostly adopted to prepare high-purity tellurium. The effectiveness of the process depends on the effectiveness of the vacuum distillation purification of tellurium, i.e. the degree to which tellurium and impurities are separated during the vacuum distillation. In theory, tellurium is a low melting point and high vapor pressure element, and the vacuum distillation process can effectively separate most impurities to obtain high-purity tellurium in vapor deposition phase. However, practice has shown that the purification effect of tellurium by vacuum distillation is much lower than expected.

For example, the chinese invention patent publication No. CN103183322B provides a method for preparing high-purity tellurium, comprising: placing a tellurium raw material in a quartz boat; horizontally placing the quartz boat filled with the tellurium raw material into a zone melting material pipe, and sealing the zone melting material pipe; introducing reducing gas; moving the zone-melting heating pipe to the head of the tellurium raw material in the quartz boat; heating and melting the head of the tellurium raw material in the quartz boat to form a melting zone, and moving the zone-melting heating pipe at a specified speed when the specified width of the melting zone is reached so as to finish one zone-melting operation; after one zone-melting operation is finished, returning the zone-melting heating pipe to the head of the tellurium raw material in the quartz boat and repeating the zone-melting operation; stopping the zone-melting operation after the repeated times of zone-melting operation is finished, and cooling the tellurium raw material after the zone-melting operation; cutting off the head part and the tail part by specified lengths respectively to complete one cycle operation, taking the residual tellurium raw material after cutting off as the tellurium raw material processed by the next cycle operation, and repeating all the steps for eight preset cycle times. The method has the advantages that the impurity removal process is complicated, and the impurity removal effect is poor; meanwhile, the production cost is high, so that the method is not beneficial to large-scale production and continuous large-scale production cannot be carried out.

For example, chinese patent application publication No. CN111924811A discloses a method for preparing ultra-high purity tellurium, which comprises placing raw material tellurium in a container with a baffle inside, positioning the raw material tellurium at one side of the baffle, heating the raw material tellurium to be completely melted under the protection of protective gas, and controlling the liquid level of the tellurium melt at the side where the raw material tellurium is positioned to be above the through hole of the baffle, so that the impurity carbon powder and oxide contained in the raw material tellurium are intercepted at one side of the baffle, thereby ensuring that the impurity content of the tellurium melt flowing to the other side through the through hole is reduced, and condensing the part of the tellurium melt for preparing ultra-high purity tellurium. By adopting the technical scheme, the impurity removal efficiency is low, and meanwhile, the method cannot ensure continuous large-scale production.

For example, the institute of metallurgy science and engineering of the university of the China and south finds that the tellurium powder is treated in 73OK hydrogen for 30 minutes, the purity of the tellurium powder is increased from 99.95% to 99.9995%, and 5N-grade high-purity tellurium can be prepared. However, the method cannot be realized for 6N-grade high-purity tellurium, and the key point is that the separation of heavy metal impurities and element selenium with similar properties cannot be realized rapidly and simply in industry.

Disclosure of Invention

The invention solves the technical problems that in the prior art, equipment for producing high-purity tellurium has high cost and complex process, and cannot meet the requirement of industrial continuous production, provides high-purity tellurium production equipment and a production process which can realize continuous production, and has the advantages of low cost, high yield, high purity and continuous production.

The technical scheme adopted by the invention is as follows: a production device of 6N-grade high-purity tellurium is characterized by comprising a material melting furnace, a heating furnace and a collecting furnace; the melting furnace is positioned above the heating furnace and is connected with the heating furnace through a discharging pipe; the heating furnace is connected with the collecting furnace through a pipeline, the pipeline is positioned on the side of the heating furnace and is provided with an air inlet, and the pipeline is positioned on the side of the collecting furnace and is provided with an air outlet; a high-purity quartz boat is arranged in the heating furnace; a heating cone and a heat preservation area are arranged in the collecting furnace, and a crucible is arranged below the heat preservation area; most of the cones of the heating cones are positioned on the same horizontal plane with the pipeline, and the cone tops of the cones are lower than the horizontal plane of the pipeline.

The production process of high-purity tellurium comprises the following steps: s1, crushing the 4N refined tellurium, and putting into a melting furnace; s2, starting to heat the melting furnace to melt the refined tellurium into a solution; s3, heating the heating furnace, and introducing hydrogen into the heating furnace through a pipeline; s4, heating the temperature in the heating furnace to 600-900 ℃, controlling the hydrogen flow rate to 3-5L/min, and keeping the hydrogen flow rate stable; s5, opening a discharge valve at the bottom of the melting furnace, and putting the melt into a high-purity quartz boat; s6, heating the heating cone until the temperature of the rear end temperature measuring hole is kept at 380-430 ℃; s7, stopping heating the heating furnace, taking out the high-purity quartz boat from the heating furnace after the temperature in the heating furnace is reduced to room temperature, replacing the high-purity quartz boat with a new one, and restarting production; and S8, opening a discharge valve at the bottom of the heat preservation area, and discharging the product into the crucible for casting.

As a further improvement of the invention, the heating furnace is a horizontal tube type heating furnace, and the hearth of the heating furnace is a high-purity quartz tube.

As a further improvement of the invention, a heating resistance wire is arranged in the heating cone, a heating resistance wire is arranged in the heat preservation area, a heating resistance wire is arranged in the melting furnace, and a heating resistance wire is arranged in the heating furnace.

As a further improvement of the invention, the heating cone and the heat preservation area are made of Hastelloy.

As a further improvement of the invention, the bottom of the melting furnace is provided with a discharge valve, and the bottom of the heat preservation area is provided with a discharge valve.

As a further improvement of the invention, in the S1, the 4N tellurium raw material is crushed into particles with the diameter of less than 1 cm.

As a further improvement of the invention, the temperature of the melting furnace is maintained at 470-500 ℃.

The invention has the following beneficial effects: the high-purity tellurium production equipment with the structure can effectively realize efficient purification of tellurium, simultaneously realize continuous feeding and continuous production, and realize industrial large-scale production. The invention has the advantages of small equipment investment, convenient control, realization of the purpose of continuous production, extension of the operation time of a single furnace and capacity improvement.

Drawings

FIG. 1 is a schematic diagram of one embodiment of the present disclosure.

Shown in the figure: the device comprises a gas outlet valve 1, a heat preservation area 2, a heating resistance wire 3, a temperature measuring sleeve 4, a heating cone 5, a discharge valve 7, a pipeline 8, a crucible 9, a melting furnace 11, a discharge pipe 13, a heating furnace 14, a high-purity quartz boat 15 and an air inlet valve 17.

Detailed Description

The invention will be further described with reference to the accompanying drawings.

As shown in the figure, the production equipment of the 6N-grade high-purity tellurium comprises a material melting furnace 11, a heating furnace 14 and a collecting furnace; the melting furnace is positioned above the heating furnace and is connected with the heating furnace through a discharging pipe 13; the heating furnace is connected with the collecting furnace through a pipeline 8, the pipeline 8 is positioned at the side of the heating furnace, an air inlet valve 17 is arranged at an air inlet, and an air outlet valve 1 is arranged at the side of the collecting furnace; a high-purity quartz boat 15 is arranged in the heating furnace; a heating cone 5 and a heat preservation area 2 are arranged in the collecting furnace, and a crucible 9 is arranged below the heat preservation area; most of the cones of the heating cones are positioned on the same horizontal plane with the pipeline, and the cone tops of the cones are lower than the horizontal plane of the pipeline.

The heating furnace is a horizontal tube type heating furnace, the hearth of the heating furnace is a high-purity quartz tube 8, and a high-purity quartz boat 15 is arranged in the hearth. The material melting furnace 11 is connected with the horizontal tube type heating furnace through a discharging pipe 13, the material melting furnace 11 melts 4N fine tellurium into a melt, the melt tellurium is placed into a high-purity quartz boat 15 in the horizontal tube type heating furnace 14 through a discharging valve 12 at the bottom of the material melting furnace, the purpose of continuous feeding is achieved, the running time of a single furnace is prolonged, and the productivity is improved.

In order to ensure the purification effect of the whole device, a heating resistance wire is arranged inside the heating cone, a heating resistance wire is arranged inside the heat preservation area, a heating resistance wire is arranged inside the material melting furnace, and a heating resistance wire is arranged inside the heating furnace. The heating cone 5 is made of hastelloy, a heating resistance wire 6 is paved inside the heating cone, the effect of temperature compensation is achieved, tellurium steam is enabled to become a melt on the cone and flows into the heat preservation area 2 below the cone, low-melting-point impurities such as hydrogen selenide and the like are discharged from the gas outlet valve 1 along the gas flow, and therefore purification of tellurium is achieved.

The heat preservation area 2 is made of hastelloy, a discharge valve 7 is arranged at the bottom of the heat preservation area, and the discharge and casting of products are controlled through the valve.

The technical principle adopted by the invention is as follows: atmospheric distillation and hydrogen impurity removal are combined to produce 6N high-purity tellurium in one step. Atmospheric distillation is used as a conventional physical separation means, is widely applied in the field of petrochemical industry, and is suitable for separating substances with larger vapor pressure difference. If only normal pressure distillation is adopted, the separation of selenium and tellurium can not be realized because the vapor pressure of selenium and tellurium under normal pressure is close, and the purity of the product can not meet the requirement; at high temperature, hydrogen and selenium can form hydrogen selenide gas, and tellurium hardly reacts with hydrogen, so that selenium and tellurium can be separated by utilizing hydrogen impurity removal, but the method can not separate heavy metal impurities, only 5N high-purity tellurium can be prepared, and the subsequent production of 6N high-purity tellurium still needs distillation impurity removal. By utilizing the advantages of the method, the normal pressure distillation is combined with the hydrogen impurity removal, so that on one hand, the investment of a vacuum system is reduced, and the purchase cost of equipment is reduced, on the other hand, the hydrogen selenium removal is combined with the normal pressure distillation, so that the heat loss in the distillation process is saved, the production cost is reduced, meanwhile, the process can realize the large-scale production of 6N high-purity tellurium in a 4N refined tellurium short flow, and the production efficiency is greatly improved. Wherein the separation of heavy metal impurities is realized by a collecting furnace.

The production equipment of the high-purity tellurium comprises the following production processes:

s1, crushing the 4N refined tellurium, and putting into a melting furnace;

s2, starting to heat the melting furnace to melt the refined tellurium into a solution;

s3, heating the heating furnace, and introducing hydrogen into the heating furnace through a pipeline;

s4, heating the temperature in the heating furnace to 600-900 ℃, controlling the hydrogen flow rate to 3-5L/min, and keeping the hydrogen flow rate stable;

s5, opening a discharge valve at the bottom of the melting furnace, and putting the melt into a high-purity quartz boat;

s6, heating the heating cone until the temperature of the rear end temperature measuring hole is kept at 380-430 ℃;

s7, stopping heating the heating furnace, taking out the high-purity quartz boat from the heating furnace after the temperature in the heating furnace is reduced to room temperature, replacing the high-purity quartz boat with a new one, and restarting production;

and S8, opening a discharge valve at the bottom of the heat preservation area, and discharging the product into the crucible for casting.

In order to ensure that the whole device is matched with the heating cone to realize the functions, the pipeline between the heating furnace and the collecting furnace is specially designed, and the pipeline is parallel to the inner cavity body of the heating furnace and most of the cone bodies of the heating cone, so that the gas coming from the heating furnace is ensured to be fully contacted with the cone bodies of the heating cone. But simultaneously, the conical top of the heating cone is lower than the plane of the pipeline, so that the tellurium vapor is ensured to be changed into a solution on the cone body and flows into the heat preservation area through the conical top, and the tellurium solution at the conical top can not contact the vapor coming from the pipeline, thereby effectively ensuring the purity of the tellurium. Meanwhile, impurities in tellurium, such as low-melting-point impurities like hydrogen selenide and the like, can be driven by gas in the pipeline and discharged from the gas outlet valve 1 along the gas flow. In order to monitor the temperature of the whole device and improve the purification effect of the hoof, a temperature measuring sleeve 4 is additionally arranged near an air outlet valve of the pipeline, so that the detection is convenient to implement. The hydrogen is used as the gas flow for pushing the tellurium steam, and is also used as impurity removing gas to react with the selenium in the tellurium steam to generate hydrogen selenide, thereby ensuring that the tellurium can reach 6N-grade high-purity tellurium.

Finally, an example of the production method of high purity tellurium in accordance with the present invention is given.

Example 1

Crushing 4N refined tellurium into small blocks of 1cm, and putting the small blocks into a material melting furnace 11; step two, the melting furnace 11 starts to heat up to 480 ℃, and the refined tellurium is melted into a melt; step three, starting to introduce hydrogen into the horizontal tube type heating furnace 14, controlling the hydrogen flow rate at 3L/min, and heating to 700 ℃; step four, when the hydrogen flow rate is stabilized at 3L/min, the temperature in the pipe is maintained at 700 ℃; step five, opening a discharge valve 12 at the bottom of the melting furnace 11, and putting the melt into a high-purity quartz boat 15; step six, heating the heating cone 6 to a temperature of the rear end temperature measuring hole which is stable at 400 ℃; and seventhly, stopping production, taking out the high-purity quartz boat 15 from the horizontal heating furnace after the temperature in the horizontal heating furnace 14 is reduced to the room temperature, and replacing the high-purity quartz boat with a new one to restart the production.

Example 2

Crushing 4N refined tellurium into small blocks of 1cm, and putting the small blocks into a material melting furnace 11; step two, the melting furnace 11 starts to heat up to 480 ℃, and the refined tellurium is melted into a melt; step three, starting to introduce hydrogen into the horizontal tube type heating furnace 14, controlling the hydrogen flow rate at 4L/min, and heating to 750 ℃; step four, when the hydrogen flow rate is stabilized at 4L/min, the temperature in the pipe is maintained at 750 ℃; step five, opening a discharge valve 12 at the bottom of the melting furnace 11, and putting the melt into a high-purity quartz boat 15; step six, heating the heating cone 6 to a temperature of the rear-end temperature measuring hole which is stable at 410 ℃; and seventhly, stopping production, taking out the high-purity quartz boat 15 from the horizontal heating furnace after the temperature in the horizontal heating furnace 14 is reduced to the room temperature, and replacing the high-purity quartz boat with a new one to restart the production.

Example 3

Crushing 4N refined tellurium into small blocks of 1cm, and putting the small blocks into a material melting furnace 11; step two, the melting furnace 11 starts to heat up to 500 ℃, and the refined tellurium is melted into a melt; step three, starting to introduce hydrogen into the horizontal tube type heating furnace 14, controlling the hydrogen flow rate at 5L/min, and heating to 900 ℃; step four, when the hydrogen flow rate is stabilized at 5L/min, the temperature in the pipe is maintained at 900 ℃; step five, opening a discharge valve 12 at the bottom of the melting furnace 11, and putting the melt into a high-purity quartz boat 15; step six, heating the heating cone 6 to a temperature of the rear-end temperature measuring hole which is stable at 420 ℃; and seventhly, stopping production, taking out the high-purity quartz boat 15 from the horizontal heating furnace after the temperature in the horizontal heating furnace 14 is reduced to the room temperature, and replacing the high-purity quartz boat with a new one to restart the production.

Finally, the results of the tests of the products of examples 1 to 3 are given, and the chemical compositions after analysis by GDMS are shown in the following table (unit: ppm).

	Example 1	Example 2	Example 3
				Te	99.9999+％	99.9999+％	99.9999+％
Mg	＜0.001	0.005	0.01
				Al	0.008	0.02	0.02
Ca	＜0.01	0.01	＜0.01
				Fe	＜0.005	0.03	0.01
Ni	0.02	0.03	0.01
				Cu	0.004	0.02	0.03
Zn	＜0.005	0.03	0.03
				Se	＜0.01	0.04	＜0.01
Ag	＜0.005	＜0.005	＜0.005
				Cd	＜0.01	0.04	＜0.01
Pb	＜0.005	0.03	0.05

According to the detection, the purification effect of Te is good, the taste of high-purity tellurium can be achieved, impurities in Te can be well removed, more importantly, the equipment is low in investment, the whole continuous feeding production of high-purity tellurium can be realized, and the production efficiency and the cost are greatly improved.

It should be understood by those skilled in the art that the protection scheme of the present invention is not limited to the above-mentioned embodiments, and various permutations, combinations and modifications can be made on the above-mentioned embodiments without departing from the spirit of the present invention, and the modifications are within the scope of the present invention.