CN114480880B

CN114480880B - Method for preparing metallic antimony by directly reducing antimony oxide powder by microwave

Info

Publication number: CN114480880B
Application number: CN202210121830.4A
Authority: CN
Inventors: 刘晨辉; 刘健; 王永利; 朱雄劲; 马至宇; 李玲博
Original assignee: Yunnan Minzu University
Current assignee: Yunnan Minzu University
Priority date: 2022-02-09
Filing date: 2022-02-09
Publication date: 2023-03-21
Anticipated expiration: 2042-02-09
Also published as: CN114480880A; ZA202301186B

Abstract

The invention discloses a method for preparing metal antimony by directly reducing antimony oxide powder by microwaves, which relates to the technical field of antimony smelting and comprises the following steps: grinding antimony oxide powder, adding a reducing agent and a fluxing agent, placing the mixture in a microwave reduction system, heating from room temperature to the reduction temperature, preserving the heat for 20-40 min, and reducing to obtain crude antimony and smoke dust; carrying out secondary reduction on the antimony oxide powder smoke dust recovered in the processes of temperature rise, heat preservation and reduction; and after the reduction is finished, closing the microwave, naturally cooling, and taking out the crude antimony and the residual slag. Compared with the traditional smelting process, the smelting process disclosed by the invention has the advantages that the reduction temperature is reduced, the reduction efficiency is improved, the smelting cost is reduced, the purity of the crude antimony obtained by reduction is high, the process flow is short, the metal direct recovery rate is high, the process is clean and environment-friendly, and the process has a wide industrial application prospect.

Description

Method for preparing metallic antimony by directly reducing antimony oxide powder by microwave

The invention relates to the technical field of antimony smelting, in particular to a method for preparing metal antimony by directly reducing antimony oxide powder by microwaves.

Background

Antimony metal is an important strategic metal resource, and plays a significant role in alloy manufacturing, military industry, flame retardant manufacturing and glass manufacturing. At present, the smelting method of the metal antimony mainly comprises a fire method and a wet method, the industrial production mainly comprises the fire method, and mainly comprises a volatilization roasting (smelting) -reduction smelting process, an oxygen-enriched intensified molten pool smelting, a molten salt smelting, a non-volatilization roasting process and the like, and the volatilization roasting (smelting) -reduction smelting process is mainly used at present. The reduction smelting process mainly takes antimony oxide powder obtained by roasting as a raw material, and the antimony oxide powder is mixed with a reducing agent and a fluxing agent according to a certain proportion and then is put into a radiation furnace for reduction. Although the method is simple and convenient to operate, the method has the problems of high energy consumption, low smelting strength, low heat efficiency, high reduction temperature, large volatilization amount of antimony oxide powder and the like. Besides, under the high-temperature condition of the reverberatory furnace, lead and iron also enter the smelting process in the form of oxides to participate in circulation, discharge is reduced, production efficiency is reduced, and smelting cost is also improved.

Under the situation that the requirements for carbon emission and environmental protection are gradually improved, the traditional pyrometallurgical process and equipment are moving towards intelligence and high efficiency. In the field of smelting of metallic antimony, smelting methods for efficiently preparing the metallic antimony are provided, the methods comprehensively improve the heat efficiency and the reduction efficiency, and effectively relieve the environmental protection pressure of smelting operation to a certain extent. CN 112410581A discloses a method for producing metal antimony from antimony oxide powder: the antimony oxide powder, the reducing agent and the flux are mixed evenly, and are granulated to obtain pellets or briquettes, and the pellets or briquettes are sent into an electromagnetic induction device or a microwave device for reduction smelting to obtain crude antimony, furnace slag and antimony oxide smoke dust. The method has high heating efficiency, saves energy consumption, greatly improves the direct recovery rate of the antimony and has high recovery rate of the antimony; but the smelting temperature of the method is higher than 1000 ℃, and no further explanation is made on a microwave reduction device. CN 102108448A discloses a reduction smelting method of antimony oxychloride slag: the raw materials, the soda ash, the lime and the solid carbon are added into a reverberatory furnace after being mixed, and are reduced for 8 to 12 hours at the temperature of 1100 to 1200 ℃, and the chlorine is solidified in the form of sodium chloride and calcium chloride, so that the environmental pollution is reduced, but the reduction temperature is high, and the smelting time is long. CN 108823432A discloses a method for reducing antimony oxide by starch in low-temperature molten salt: antimony oxide and starch are mixed, granulated and dried, and then reduced in low-temperature molten salt, and the method has the advantages that the reduction temperature is reduced to 600-750 ℃, but the flow needs three stages, the requirement on raw materials is high, and the method is not applied on a large scale. CN 105603197A discloses a device for smelting antimony by directly reducing antimony slag and antimony soot and a process thereof: antimony soot and fly ash generated in the smelting process are blown into a reduction furnace through a spray gun, so that the reduction efficiency is improved, but the method has higher environmental pressure and smaller treatment capacity, and is difficult to cope with large-scale antimony smelting.

Aiming at the current energy environmental protection requirements of low antimony smelting efficiency and energy conservation and emission reduction, a low-temperature and high-efficiency antimony smelting method is needed to be provided.

Disclosure of Invention

The invention provides a method for directly preparing metal antimony by efficiently reducing antimony oxide powder at low temperature by microwave, aiming at the problems of high energy consumption, low production efficiency, large smoke gas amount, high reduction temperature, large volatilization amount of antimony oxide powder and the like in the traditional antimony smelting process.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides a method for preparing metallic antimony by directly reducing antimony oxide powder by microwaves, which comprises the following steps: grinding antimony oxide powder, adding a reducing agent and a fluxing agent, placing the mixture in a microwave reaction system, inserting a thermocouple into the material, quickly heating the material from room temperature to a reduction temperature, preserving the temperature for 20-40 min to obtain crude antimony and smoke dust, wherein the smoke dust is antimony oxide powder smoke dust, and returning the crude antimony oxide powder smoke dust to the microwave reduction system for secondary reduction. Carrying out secondary reduction on the antimony oxide powder smoke dust recovered in the processes of rapid heating, heat preservation and reduction; and after the reduction is finished, closing the microwave, naturally cooling, and taking out the crude antimony and the residual slag.

The antimony oxide powder and the coke powder both have good dielectric properties, and the specific parameters are as follows: the dielectric constant of the antimony oxide powder is 8-15, and the dielectric loss is 0.1-0.3; the dielectric constant of the coke powder is 6-15, the dielectric loss is 0.2-0.3, which shows that the antimony oxide powder and the coke can be rapidly heated in a microwave field and the wave-absorbing performance is excellent. Before the antimony oxide reaches the melting point (655 ℃), the reducing agent such as coke powder is volatilized rapidly preferentially to create a good reducing atmosphere, and then the reduction of the antimony oxide is realized at a lower temperature (due to the high solid-gas reaction rate).

Further, the antimony oxide powder contains 70-80% of antimony, 20-25% of oxygen and 5% of total impurities by mass, and is ground to 50-200 meshes.

Further, the reducing agent is coke, anthracite, carbon powder or activated carbon; the fluxing agent is sodium carbonate, sodium chloride or calcium fluoride.

Further, the mass ratio of the antimony oxide powder to the reducing agent to the fluxing agent is 1: (0.1-0.3): (0.01-0.05).

Furthermore, the mixed material is placed in a ceramic or corundum crucible, the thickness of the material layer is 1-10 cm, and the mixed material is placed in a microwave reaction system.

Furthermore, the microwave power in the microwave reaction system is 0.1-20 kW, the power is continuously adjustable, the frequency is 2450Hz +/-50 Hz or 915Hz +/-50 Hz, and the heating rate is 50-120 ℃/min.

Further, the reduction temperature is 700-900 ℃, and the heat preservation time is 20-40 min.

The microwave reaction system comprises a microwave reduction reaction cavity, a microwave source, a waveguide, a high-temperature dust collecting pipeline, a dust collector, a crucible, a thermocouple, a heat insulation material and a numerical control system.

And further, after the smoke dust obtained by microwave reduction is discharged from an air outlet of the microwave reaction system, recovering the smoke dust by using a high-temperature dust collecting system, and performing secondary reduction after collection.

Furthermore, the microwave reduction cavity is a rectangular resonant cavity and is connected with a microwave source through a rectangular waveguide.

The method has the advantages of low-temperature efficient direct reduction of antimony oxide, short process flow, little environmental pollution and simple operation; the antimony oxide and the coke powder quickly absorb microwave energy to quickly reach the reaction atmosphere of antimony reduction, the material heating efficiency is high, the reaction rate is high, the obtained product has good quality, the reaction temperature can be effectively reduced, the volatilization of antimony oxide powder in the whole reduction process is reduced, and the aim of microwave smelting is fulfilled. The microwave greatly improves the reduction efficiency and reduces the energy consumption in the smelting process. In the microwave heating process, the direct-insertion thermocouple can directly measure the real-time temperature of the material, and the temperature measurement is accurate. And for a small amount of volatilized antimony oxide powder, the antimony oxide powder can be collected by a flue gas treatment system and used for secondary smelting or direct use, so that the waste of the antimony oxide powder is avoided. The produced crude antimony can be directly separated from the reducing agent and the flux, and the antimony metal rate of the crude antimony is more than 97%.

Compared with the traditional reverberatory furnace for antimony smelting, the microwave heating source of the invention can reduce the whole reduction reaction temperature by 200-400 ℃, and the metal recovery rate reaches more than 90%.

Drawings

FIG. 1 is a flow chart of an embodiment of the method of the present invention.

FIG. 2 is a schematic diagram of a microwave reduction system adopted by the invention, which comprises a microwave reduction reaction cavity, a microwave source, a waveguide, a high-temperature dust collection system, a crucible, a heat insulation material and a numerical control system.

Detailed Description

Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but rather as a more detailed description of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In addition, for numerical ranges in the present disclosure, it is understood that each intervening value, to the upper and lower limit of that range, is also specifically disclosed. Every intervening value, to the extent any stated value or intervening value in a stated range, and any other stated or intervening value in a stated range, is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The description and examples are intended to be illustrative only.

As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.

The flow chart of the implementation of the process of the invention is shown in FIG. 1. The schematic diagram of the microwave reaction system adopted by the invention is shown in figure 2, wherein the microwave reaction system comprises a high-temperature dust collecting pipeline, a dust collector, materials, a crucible, a numerical control panel, a water cooler, a waveguide and a magnetron.

In the raw material antimony oxide powder used in the embodiment of the invention, the mass percentage of antimony is 70-80%, the mass percentage of oxygen is 20-25%, and the total impurity content is about 5%. The content of the fixed carbon of the reducing agent is 75-90%, the content of the volatile component is 7-17%, and the content of the ash is 3-6%.

Example 1

Firstly, grinding antimony oxide powder to 200 meshes, and then mixing the antimony oxide powder, the coke powder and sodium carbonate according to a mass ratio of 1:0.12:0.02 g of the mixture is uniformly mixed, 200g of the mixture is placed in a corundum crucible, the thickness of a material layer is 5cm, the corundum crucible is placed in a cavity of a microwave heating system, and a thermocouple is inserted into the material. And (3) starting a power supply, and regulating the output microwave power to be 2kW and the output frequency to be 2450MHz +/-50 Hz through a microwave controller of the microwave equipment. Real-time observation is carried out through a temperature display of the microwave reactor, the temperature rise rate is controlled to be 50 ℃/min, the temperature is rapidly raised to 700 ℃, the temperature is controlled to be 700 ℃, the temperature is kept for 30min, generated flue gas is recycled in real time by using high-temperature dust collection equipment in the temperature rise stage and the heat preservation process, and antimony oxide powder in the high-temperature dust collection is uniformly mixed together for secondary reduction. And after the reduction is finished, closing the microwave. And naturally cooling, and taking out crude antimony and slag, wherein the metal rate of the obtained crude antimony is 97.72%, and the metal recovery rate is 91.28%.

Example 2

Firstly, grinding antimony oxide powder to 200 meshes, and then mixing the antimony oxide powder, the coke powder and sodium carbonate according to a mass ratio of 1:0.13:0.03, uniformly mixing, placing 200g of the mixture into a corundum crucible, placing the corundum crucible into a cavity of a microwave heating system, and inserting a thermocouple into the material, wherein the thickness of a material layer is 5 cm. And (3) starting a power supply, and regulating the output microwave power to be 2kW and the output frequency to be 2450MHz +/-50 Hz through a microwave controller of the microwave equipment. Real-time observation is carried out through a temperature display of the microwave reactor, the temperature rise rate is controlled to be 50 ℃/min, the temperature is rapidly raised to 800 ℃, the temperature is controlled to be 800 ℃, the temperature is kept for 30min, generated flue gas is recycled in real time by using high-temperature dust collection equipment in the temperature rise stage and the heat preservation process, and antimony oxide powder in the high-temperature dust collection is uniformly mixed together for secondary reduction. And after the reduction is finished, closing the microwave. Naturally cooling, taking out crude antimony and furnace slag, wherein the metal rate of the obtained crude antimony is 98.83%, and the metal recovery rate is 94.49%

Example 3

Firstly, grinding antimony oxide powder to 200 meshes, and then mixing the antimony oxide powder, the coke powder and sodium carbonate according to a mass ratio of 1:0.18:0.04, uniformly mixing, placing 200g of the mixture into a corundum crucible, placing the corundum crucible into a cavity of a microwave heating system, and inserting a thermocouple into the material. And (3) starting a power supply, and regulating the output microwave power to be 2.5kW and the output frequency to be 2450MHz +/-50 Hz by a microwave controller of the microwave equipment. Real-time observation is carried out through a temperature display of the microwave reactor, the temperature rise rate is controlled to be 50 ℃/min, the temperature is rapidly raised to 900 ℃, the temperature is controlled to be 900 ℃, the temperature is kept for 30min, generated flue gas is recycled in real time by using high-temperature dust collection equipment in the temperature rise stage and the heat preservation process, and antimony oxide powder in the high-temperature dust collection is uniformly mixed together for secondary reduction. And after the reduction is finished, closing the microwave. Naturally cooling, taking out crude antimony and slag, wherein the metal rate of the obtained crude antimony is 99.12%, and the metal recovery rate is 96.42%

Example 4

Grinding antimony oxide powder to 180 meshes, and then mixing the antimony oxide powder, the coke powder and sodium carbonate according to a mass ratio of 1:0.20:0.045, putting 200g of the mixture into a corundum crucible, putting the corundum crucible into a cavity of a microwave heating system, and inserting a thermocouple into the material, wherein the thickness of a material layer is 6 cm. And (3) starting a power supply, and regulating the output microwave power to be 3kW and the output frequency to be 2450MHz +/-50 Hz by a microwave controller of the microwave equipment. Real-time observation is carried out through a temperature display of the microwave reactor, the temperature rise rate is controlled to be 70 ℃/min, the temperature is rapidly raised to 800 ℃, the temperature is controlled to be 800 ℃, the temperature is kept for 20min, generated flue gas is recycled in real time by using high-temperature dust collection equipment in the temperature rise stage and the heat preservation process, and antimony oxide powder in the high-temperature dust collection is uniformly mixed together for secondary reduction. And after the reduction is finished, closing the microwave. And naturally cooling, and taking out crude antimony and slag, wherein the metal rate of the obtained crude antimony is 98.23%, and the metal recovery rate is 92.53%.

Example 5

Grinding antimony oxide powder to 180 meshes, and then mixing the antimony oxide powder, the coke powder and sodium carbonate according to a mass ratio of 1:0.18:0.050 g of the mixture was uniformly mixed, 200g of the mixture was placed in a corundum crucible, the thickness of the material layer was 6cm, the corundum crucible was placed in a cavity of a microwave heating system, and a thermocouple was inserted into the material. And (3) starting a power supply, and regulating the output microwave power to be 3kW and the output frequency to be 2450MHz +/-50 Hz by a microwave controller of the microwave equipment. Real-time observation is carried out through a temperature display of the microwave reactor, the temperature rise rate is controlled to be 70 ℃/min, the temperature is rapidly raised to 800 ℃, the temperature is controlled to be 800 ℃, the temperature is kept for 40min, generated flue gas is recycled in real time by using high-temperature dust collection equipment in the temperature rise stage and the heat preservation process, and antimony oxide powder in the high-temperature dust collection is uniformly mixed together for secondary reduction. And after the reduction is finished, closing the microwave. And naturally cooling, and taking out crude antimony and slag, wherein the metal rate of the obtained crude antimony is 99.18%, and the metal recovery rate is 95.62%.

Example 6

Grinding antimony oxide powder to 80 meshes, and then mixing the antimony oxide powder, the coke powder and sodium carbonate according to a mass ratio of 1:0.10:0.03, uniformly mixing, placing 200g of the mixture into a corundum crucible, placing the corundum crucible into a cavity of a microwave heating system, and inserting a thermocouple into the material, wherein the thickness of a material layer is 3 cm. And (3) starting a power supply, and regulating the output microwave power to be 4kW and the output frequency to be 2450MHz +/-50 Hz through a microwave controller of the microwave equipment. Real-time observation is carried out through a temperature display of the microwave reactor, the temperature rise rate is controlled to be 90 ℃/min, the temperature is rapidly raised to 850 ℃, the temperature is controlled to be 850 ℃, heat preservation is carried out for 25min, generated flue gas is recycled in real time by using high-temperature dust collection equipment in the temperature rise stage and the heat preservation process, and antimony oxide powder in the high-temperature dust collection is uniformly mixed for secondary reduction. And after the reduction is finished, closing the microwave. And naturally cooling, and taking out the crude antimony and the slag, wherein the metal rate of the obtained crude antimony is 98.44%, and the metal recovery rate is 95.38%.

Example 7

Grinding antimony oxide powder to 120 meshes, and then mixing the antimony oxide powder, the coke powder and sodium carbonate according to a mass ratio of 1:0.15:0.05, uniformly mixing, placing 200g of the mixture into a corundum crucible, placing the corundum crucible into a cavity of a microwave heating system, and inserting a thermocouple into the material. And (3) starting a power supply, and regulating the output microwave power to be 5kW and the output frequency to be 2450MHz +/-50 Hz through a microwave controller of the microwave equipment. Real-time observation is carried out through a temperature display of the microwave reactor, the temperature rise rate is controlled to be 100 ℃/min, the temperature is rapidly raised to 850 ℃, the temperature is controlled to be 850 ℃, the temperature is kept for 30min, generated flue gas is recycled in real time by using high-temperature dust collection equipment in the temperature rise stage and the heat preservation process, and antimony oxide powder in the high-temperature dust collection is uniformly mixed together for secondary reduction. And after the reduction is finished, closing the microwave. And naturally cooling, and taking out crude antimony and slag, wherein the metal rate of the obtained crude antimony is 99.22%, and the metal recovery rate is 95.53%.

Example 8

Grinding antimony oxide powder to 150 meshes, and then mixing the antimony oxide powder, the coke powder and sodium carbonate according to a mass ratio of 1:0.15:0.05, uniformly mixing, placing 200g of the mixture into a corundum crucible, placing the corundum crucible into a cavity of a microwave heating system, and inserting a thermocouple into the material. And (3) starting a power supply, and regulating the output microwave power to be 6kW and the output frequency to be 2450MHz +/-50 Hz by a microwave controller of the microwave equipment. Real-time observation is carried out through a temperature display of the microwave reactor, the temperature rise rate is controlled to be 100 ℃/min, the temperature is rapidly raised to 900 ℃, the temperature is controlled to be 900 ℃, the temperature is kept for 35min, generated flue gas is recycled in real time by using high-temperature dust collection equipment in the temperature rise stage and the heat preservation process, and antimony oxide powder in the high-temperature dust collection is uniformly mixed together for secondary reduction. And after the reduction is finished, closing the microwave. And naturally cooling, and taking out crude antimony and slag, wherein the metal rate of the obtained crude antimony is 99.35%, and the metal recovery rate is 96.63%.

Example 9

The differences from example 2 are: the reducing agent is activated carbon. The crude antimony had a metal yield of 98.92% and a metal recovery of 95.3%.

Example 10

The differences from example 2 are: the reducing agent is anthracite. The metal yield of the obtained crude antimony was 97.23%, and the metal recovery rate was 92.1%.

Example 11

The differences from example 2 are: the fluxing agent used was sodium chloride. The metal rate of the obtained crude antimony is 98.34%, and the metal recovery rate is 94.57%.

Example 12

The differences from example 2 are: the fluxing agent used was calcium fluoride. The metal rate of the obtained crude antimony is 99.31%, and the metal recovery rate is 94.78%.

Example 13

The differences from example 2 are: the microwave frequency used was 915M MHz. + -. 50Hz. The crude antimony had a metal yield of 98.93% and a metal recovery of 95.38%.

Comparative example 1

The same procedure as in example 2 was followed, except that the reduction temperature was 600 ℃ and the holding time was 1 hour. The crude antimony of the reduction product can not be obtained, and only antimony particles are obtained.

Comparative example 2

The method is the same as the method in the embodiment 2, except that only antimony oxide and carbon powder are used in the material proportioning, sodium chloride or sodium carbonate and other fluxing agents are not added, the obtained antimony is granular, the crude antimony metal rate is 84.35%, and the metal recovery rate is 82.21%.

Comparative example 3

The same procedure as in example 2 was followed, except that the material was placed in a muffle furnace for reduction melting. The reduction temperature is 1100 ℃, and the heat preservation time is 1h. The volatilization rate is 25.36 percent, the crude antimony metal rate is 97.32 percent, and the metal recovery rate is 82.35 percent.

As is clear from comparative examples 1, 2 and 3, the temperature of the whole reduction system is limited to 700 to 900 ℃ and preferably 800 to 900 ℃ and the metal reduction rate is 90% or more.

Comparing examples 3, 4, 5 and 6, it can be seen that the heat preservation time of the whole reduction system is limited within 20-40 min, which is beneficial to shortening the reduction time and reducing the volatilization rate of antimony oxide.

It is understood from comparative examples 5, 6, 7 and 8 that the particle size of antimony oxide powder is controlled to be within 200 mesh, which is advantageous for improving the metal reduction rate. The material thickness of the reduction system is controlled to be 1-10 cm.

As can be seen from comparative examples 1, 6 and 7, the mass ratio of antimony oxide powder, reducing agent and flux in the whole reduction system was defined as 1: (0.1-0.3): (0.01-0.05), the metal recovery rate is more than 90%.

As can be seen from comparative examples 1, 11, 12 and 13, the reducing agent of the whole reduction system can be carbon powder, activated carbon or anthracite; the fluxing agent may be sodium carbonate, sodium chloride or calcium fluoride.

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.

Claims

1. A method for preparing metallic antimony by directly reducing antimony oxide powder by microwaves is characterized by comprising the following steps:

grinding antimony oxide powder to 180 meshes, and then mixing the antimony oxide powder, the coke powder and sodium carbonate according to a mass ratio of 1:0.20:0.045, uniformly mixing, putting 200g of the mixture into a corundum crucible, setting the material layer with the thickness of 6cm, putting the corundum crucible into a cavity of a microwave heating system, inserting a thermocouple into the material, starting a power supply, regulating the output microwave power to be 3kW and the output frequency to be 2450MHz +/-50 Hz by a microwave controller of microwave equipment, observing the mixture in real time by a temperature display of a microwave reactor, controlling the heating rate to be 70 ℃/min, rapidly heating to 800 ℃, controlling the temperature to be 800 ℃ and keeping the temperature for 20min, carrying out real-time recovery on generated flue gas by high-temperature equipment in the heating stage and the heat preservation process, uniformly mixing antimony oxide powder in the high-temperature dust collection to carry out secondary reduction, closing the microwave dust collection after the reduction is finished, naturally cooling, taking out crude antimony and furnace slag, wherein the metal rate of the obtained crude antimony is 98.23%, and the metal recovery rate is 92.53%.