Preparation method of high-purity antimony trichloride and high-purity antimony

Abstract

The invention provides a preparation method of high-purity antimony trichloride and high-purity antimony, and belongs to the technical field of chemical production processes. The method provided by the invention comprises the following steps: carrying out chlorination reaction on antimony particles in top-blown chlorine-containing gas, side-blown chlorine-containing gas and bottom-blown chlorine-containing gas to obtain antimony trichloride gas; the top-blown chlorine-containing gas, the side-blown chlorine-containing gas and the bottom-blown chlorine-containing gas are mixed gas of chlorine and shielding gas; condensing and crystallizing part of the antimony trichloride gas in sequence to obtain high-purity antimony trichloride; the rest antimony trichloride gas is subjected to a reduction reaction in bottom blowing hydrogen-containing gas, and high-purity antimony is obtained; the hydrogen-containing gas is mixed gas of hydrogen and protective gas. According to the method, the uniformity and efficiency of the chlorination reaction can be effectively controlled in a top-side bottom-blowing multi-point gas inlet mode, high-purity antimony trichloride and high-purity antimony are obtained, the antimony trichloride preparation process is greatly simplified, and the method is suitable for industrial production.

Description

Technical Field

[0001] The invention relates to the technical field of chemical production technology, and in particular to a method for preparing high-purity antimony trichloride and high-purity antimony. Background Art

[0002] High-purity antimony is mainly used to produce semiconductor compounds such as indium antimonide, gallium antimonide, and aluminum antimonide. Due to the similarity of their properties, arsenic, lead, and bismuth become impurities that are difficult to remove during the production of high-purity antimony, resulting in excessive levels of arsenic, lead, bismuth, and other impurities in antimony products prepared by traditional processes. At present, there are two main methods for preparing high-purity antimony: physical purification and chemical purification. Physical purification mainly uses the high vapor pressure of metallic antimony to separate it from other metals. The chemical method mainly removes impurity metals by adding impurity removers. However, the current physical purification has high requirements for raw materials and it is difficult to stably produce high-purity antimony; chemical purification has problems such as complex process, long flow, and high reagent consumption, which limits industrial production.

[0003] Antimony trichloride is an important chemical reagent. The common method is to crush the antimony ingot and place it in a reactor, introduce chlorine gas for chlorination reaction to generate antimony trichloride, remove antimony pentachloride by vacuum distillation, and then remove arsenic by heating, cool and crystallize, and crush to obtain the finished antimony trichloride. This method has a long process flow and complex process, which limits industrial production.

[0004] Therefore, there is an urgent need to provide a method for preparing high-purity antimony trichloride and high-purity antimony with a short process flow, low reagent usage, and suitable for industrial production. Summary of the invention

[0005] The object of the present invention is to provide a method for preparing high-purity antimony trichloride and high-purity antimony. The preparation method provided by the present invention has a short process flow, a small amount of reagents, and is suitable for industrial production.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a method for preparing high-purity antimony trichloride and high-purity antimony, comprising the following steps:

[0008] (1) subjecting antimony particles to a chlorination reaction in a top-blown chlorine-containing gas, a side-blown chlorine-containing gas, and a bottom-blown chlorine-containing gas to obtain antimony trichloride gas; wherein the top-blown chlorine-containing gas, the side-blown chlorine-containing gas, and the bottom-blown chlorine-containing gas are mixed gases of chlorine gas and protective gas;

[0009] (2) condensing and crystallizing the antimony trichloride gas obtained in step (1) to obtain high-purity antimony trichloride;

[0010] (3) subjecting the remaining portion of the antimony trichloride gas obtained in step (1) to a reduction reaction in a bottom-blown hydrogen-containing gas to obtain high-purity antimony; the hydrogen-containing gas is a mixed gas of hydrogen and protective gas.

[0011] Preferably, the purity of the antimony particles in step (1) is 99.9% to 99.91%.

[0012] Preferably, the purity of the protective gas in step (1) and step (3) is independently ≥ 99.999%.

[0013] Preferably, the flow rate of the top-blown chlorine-containing gas in step (1) is 0.05-0.1 m / s, and the volume ratio of chlorine gas to protective gas in the top-blown chlorine-containing gas is (25-39):(30-70).

[0014] Preferably, the flow rate of the side-blown chlorine-containing gas in step (1) is 0.08-0.15 m / s, and the volume ratio of chlorine gas to protective gas in the side-blown chlorine-containing gas is (0.8-1):(0.15-0.2).

[0015] Preferably, the flow rate of the bottom-blown chlorine-containing gas in step (1) is 0.1-0.3 m / s, and the volume ratio of chlorine gas to protective gas in the bottom-blown chlorine-containing gas is (2-5):(95-98).

[0016] Preferably, in step (1), the mass ratio of chlorine gas to antimony particles in the top-blown chlorine-containing gas, the side-blown chlorine-containing gas and the bottom-blown chlorine-containing gas is 1:(1.35-1.65).

[0017] Preferably, the temperature of the chlorination reaction in step (1) is 750-1000°C.

[0018] Preferably, in step (3), the mass ratio of antimony trichloride gas to hydrogen in the hydrogen-containing gas is 1:(1.35-1.65).

[0019] Preferably, the temperature of the reduction reaction in step (3) is 1000-1300°C.

[0020] The invention provides a preparation method of high-purity antimony trichloride and high-purity antimony, comprising the following steps: subjecting antimony particles to a chlorination reaction in a top-blown chlorine-containing gas, a side-blown chlorine-containing gas and a bottom-blown chlorine-containing gas to obtain an antimony trichloride gas; the top-blown chlorine-containing gas, the side-blown chlorine-containing gas and the bottom-blown chlorine-containing gas are mixed gases of chlorine and protective gas; a part of the antimony trichloride gas is sequentially condensed and crystallized to obtain high-purity antimony trichloride; and the remaining part of the antimony trichloride gas is subjected to a reduction reaction in a bottom-blown hydrogen-containing gas to obtain high-purity antimony; the hydrogen-containing gas is a mixed gas of hydrogen and protective gas. In the present invention, the principle of the chlorination reaction is: 2Sb+3Cl2→2SbCl3. In the present invention, a mixed gas of chlorine and protective gas reacts with antimony particles. The protective gas can prevent local overheating and protect the atmosphere, and at the same time avoid excessive accumulation of chlorine to cause side reactions, thereby improving the purity of antimony trichloride. The present invention promotes the circulation of hydrogen-containing gas by bottom blowing, and side blowing promotes full reaction of chlorine and antimony particles. Top blowing slowly replenishes chlorine to avoid disturbing gas distribution. The present invention can effectively control the uniformity and efficiency of the chlorination reaction by blowing multiple points of air on the top side, and improve the purity of the product antimony trichloride gas. Therefore, the obtained antimony trichloride gas is condensed and crystallized in turn to obtain high-purity antimony trichloride, which greatly simplifies the process of preparing antimony trichloride. In the present invention, the antimony trichloride gas is subjected to a reduction reaction in the bottom-blown hydrogen-containing gas: 2SbCl3+3H2→2Sb+6HCl. Since the purity of the prepared antimony trichloride is relatively high, it is subjected to a reduction reaction in the bottom-blown hydrogen-containing gas to obtain high-purity antimony. The results of the embodiments show that the purity of the high-purity antimony trichloride prepared by the present invention is ≥99.99999% (≥7N), and the purity of the high-purity antimony is ≥99.99999% (≥7N), and high-purity antimony trichloride and high-purity antimony element can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The present invention provides a process flow chart for preparing high-purity antimony trichloride and high-purity antimony. DETAILED DESCRIPTION

[0022] The present invention provides a method for preparing high-purity antimony trichloride and high-purity antimony, comprising the following steps:

[0023] (1) subjecting antimony particles to a chlorination reaction in a top-blown chlorine-containing gas, a side-blown chlorine-containing gas, and a bottom-blown chlorine-containing gas to obtain antimony trichloride gas; wherein the top-blown chlorine-containing gas, the side-blown chlorine-containing gas, and the bottom-blown chlorine-containing gas are mixed gases of chlorine gas and protective gas;

[0024] (2) condensing and crystallizing the antimony trichloride gas obtained in step (1) to obtain high-purity antimony trichloride;

[0025] (3) subjecting the remaining portion of the antimony trichloride gas obtained in step (1) to a reduction reaction in a bottom-blown hydrogen-containing gas to obtain high-purity antimony; the hydrogen-containing gas is a mixed gas of hydrogen and protective gas.

[0026] The invention conducts chlorination reaction on antimony particles in top-blown chlorine-containing gas, side-blown chlorine-containing gas and bottom-blown chlorine-containing gas to obtain antimony trichloride gas.

[0027] In the present invention, the purity of the antimony particles is preferably 99.9% to 99.91%. The present invention has no special limitation on the source of the antimony particles, and any conventional commercially available antimony particles with a purity within the above range can be used. In an embodiment of the present invention, the antimony particles can be Shanxing brand No. 1 antimony ingots.

[0028] In the present invention, the particle size of the antimony particles is preferably 1 to 1.5 cm, more preferably 1 to 1.3 cm. The antimony particles of the above particle size used in the present invention are more conducive to a more complete reaction with chlorine.

[0029] In the present invention, the top-blown chlorine-containing gas, the side-blown chlorine-containing gas and the bottom-blown chlorine-containing gas are mixed gases of chlorine gas and protective gas.

[0030] In the present invention, the purity of the chlorine is preferably ≥ 99.999%. The present invention uses high-purity chlorine as a raw material for the chlorination reaction, which can reduce the impurity content of antimony trichloride.

[0031] In the present invention, the protective gas is preferably an inert gas or nitrogen, more preferably nitrogen. In the present invention, the purity of the protective gas is preferably ≥99.999%. The present invention uses a high-purity protective gas to prevent local overheating and protect the atmosphere, while avoiding excessive accumulation of chlorine gas to cause side reactions, thereby improving the purity of antimony trichloride.

[0032] In the present invention, the flow rate of the top-blown chlorine-containing gas is preferably 0.05-0.1 m / s, more preferably 0.06-0.08 m / s. The present invention can slowly replenish chlorine by top-blowing chlorine-containing gas to avoid disturbing gas distribution, thereby allowing antimony particles to react more fully with chlorine.

[0033] In the present invention, the volume ratio of chlorine to protective gas in the top-blown chlorine-containing gas is preferably (25-39): (30-70), and more preferably (30-39): (40-61). The main function of the top-blown chlorine-containing gas in the present invention is to slowly replenish chlorine to avoid disturbing gas distribution. The present invention controls the volume ratio of chlorine to protective gas in the chlorine-containing gas within the above range, which is more conducive to a more complete reaction between antimony particles and chlorine.

[0034] In the present invention, the flow rate of the side-blown chlorine-containing gas is preferably 0.08 to 0.15 m / s, more preferably 0.1 to 0.12 m / s. The present invention promotes a full reaction between chlorine and antimony particles by side-blowing.

[0035] In the present invention, the volume ratio of chlorine gas to protective gas in the side-blown chlorine-containing gas is preferably (0.8-1): (0.15-0.2), and more preferably (0.9-1): (0.17-0.2). The present invention controls the volume ratio of chlorine gas to protective gas in the chlorine-containing gas within the above range, and a higher chlorine content in the chlorine gas can promote a full reaction between chlorine gas and antimony particles.

[0036] The present invention does not specifically limit the specific position of the side blowing, and it can be adjusted according to the chlorination device used, and can be adjusted between top blowing and bottom blowing.

[0037] In the present invention, the flow rate of the bottom-blown chlorine-containing gas is preferably 0.1-0.3 m / s, more preferably 0.2-0.3 m / s. The present invention promotes gas circulation through bottom blowing to increase the contact area between antimony particles and chlorine-containing gas.

[0038] In the present invention, the volume ratio of chlorine to protective gas in the bottom-blown chlorine-containing gas is preferably (2-5): (95-98), and more preferably (2-4): (96-98). In the present invention, the main function of bottom blowing is to promote gas circulation. The present invention controls the volume ratio of chlorine to protective gas in the chlorine-containing gas within the above range, which can meet the needs of chlorination reaction at a lower chlorine content and promote gas circulation.

[0039] In the present invention, the molar ratio of chlorine gas to antimony particles in the top-blown chlorine-containing gas, the side-blown chlorine-containing gas and the bottom-blown chlorine-containing gas is preferably 1:(1.35-1.65), and more preferably 1:(1.4-1.6). The present invention controls the molar ratio of chlorine gas to antimony particles within the above range, and can react more fully with antimony particles when chlorine-containing gas is introduced at multiple points of top, side and bottom blowing, thereby obtaining antimony trichloride with higher purity.

[0040] In the present invention, the temperature of the chlorination reaction is preferably 750-1000° C., more preferably 800-950° C. The present invention controls the temperature of the chlorination reaction within the above range to provide a suitable temperature for the chlorination reaction. The present invention has no special limitation on the time of the chlorination reaction, which can be adjusted according to the amount of antimony particles used, so that the antimony particles are completely converted into antimony trichloride.

[0041] The present invention has no special limitation on the device for the chlorination reaction, and any conventional chlorination furnace can be used.

[0042] After obtaining the antimony trichloride gas, the present invention sequentially condenses and crystallizes part of the antimony trichloride gas to obtain high-purity antimony trichloride.

[0043] The present invention has no special limitation on the amount of the antimony trichloride gas, and the amount of the antimony trichloride gas can be adjusted according to the amount of antimony trichloride required.

[0044] In the present invention, the condensation temperature is preferably 80-150° C., more preferably 90-110° C. The present invention controls the condensation temperature within the above range, efficiently condenses and reduces energy consumption, and can fully cool the antimony trichloride gas to liquid antimony trichloride mother liquor.

[0045] In the present invention, the gas flow rate of antimony trichloride gas during condensation is preferably 0.5 to 1 m 2 / m 3 / s, more preferably 0.6 to 1 m 2 / m 3 / s. The present invention controls the gas flow rate of antimony trichloride gas within the above range, which is more conducive to sufficient heat exchange with the condensing medium and sufficient condensation of antimony trichloride. The present invention does not specifically limit the specific type of the condensing medium, and any conventional condensing medium can be used. In an embodiment of the present invention, the condensing medium can be water or ethanol solution, and the flow rate of the condensing medium can be 0.5 to 1 m / s. 3 / h.

[0046] The present invention has no special limitation on the condensation device, and a conventional condenser may be used.

[0047] The present invention preferably recycles the non-condensable gas generated after the condensation. In the present invention, the components of the non-condensable gas include antimony trichloride gas that has not condensed into liquid, protective gas and unreacted chlorine gas, etc. The present invention can reduce production costs by recycling the non-condensable gas and using it again for chlorination reaction.

[0048] The present invention has no special limitation on the method for recycling the non-condensable gas, and any conventional method for recycling gas may be used.

[0049] In the present invention, the crystallization temperature is preferably -10 to 10°C, more preferably -10 to 0°C; the crystallization time is preferably 4 to 6 hours, more preferably 5 to 6 hours. The present invention can fully crystallize antimony trichloride in antimony trichloride mother liquor to obtain high-purity antimony trichloride by crystallizing at the above temperature.

[0050] The present invention conducts a reduction reaction on the remaining part of the antimony trichloride gas in a bottom-blown hydrogen-containing gas to obtain high-purity antimony.

[0051] In the present invention, the hydrogen-containing gas is a mixed gas of hydrogen and protective gas.

[0052] In the present invention, the purity of the hydrogen is preferably ≥99.999%. The present invention uses high-purity hydrogen to reduce the impurity content of high-purity antimony.

[0053] In the present invention, the protective gas is preferably an inert gas or nitrogen, more preferably nitrogen. In the present invention, the purity of the protective gas is preferably ≥ 99.999%. The present invention uses a high-purity protective gas, which can prevent local overheating and protect the atmosphere.

[0054] In the present invention, the molar ratio of the antimony trichloride gas to the hydrogen in the hydrogen-containing gas is preferably 1:(1.35-1.65), and more preferably 1:(1.4-1.6). The present invention controls the molar ratio of the antimony trichloride gas to the hydrogen in the hydrogen-containing gas within the above range, so that the antimony trichloride gas can be fully reduced to high-purity antimony.

[0055] In the present invention, the volume ratio of hydrogen to protective gas is preferably 1:(9-49), more preferably 1:(19-39). The present invention controls the volume ratio of hydrogen to protective gas within the above range, which can control the rate of the reduction reaction and enable antimony trichloride to be fully reduced to high-purity antimony.

[0056] In the present invention, the temperature of the reduction reaction is preferably 1000-1300° C., more preferably 1100-1200° C. The present invention has no particular limitation on the time of the reduction reaction, which can be adjusted according to the amount of antimony trichloride gas used to fully reduce the antimony to high purity.

[0057] The present invention preferably recycles the product gas generated by the reduction reaction. In the present invention, the components of the product gas preferably include hydrogen chloride, a product of the reduction reaction, a protective gas, and unreacted hydrogen, etc. The present invention can reduce production costs by recycling the product gas. The present invention does not specifically limit the method for recycling the product gas, and any conventional method for recycling tail gas can be used.

[0058] In an embodiment of the present invention, the method for recovering the product gas can be: condensing the product gas at -20 to 5°C to recover liquid hydrogen chloride, gasifying it to form hydrogen chloride gas which is introduced into a chlorination furnace; and returning the uncondensed hydrogen gas to a reduction furnace for reduction reaction.

[0059] The process flow chart for preparing high-purity antimony trichloride and high-purity antimony according to the present invention is preferably as follows Figure 1 As shown. Figure 1It can be seen that the present invention passes antimony particles with a purity of 99.9% into the chlorination furnace, and then blows a mixture of chlorine and nitrogen from the top side, and the obtained part of the antimony trichloride gas is passed into the condenser for condensation to obtain antimony trichloride mother liquor, and the antimony trichloride mother liquor is crystallized to obtain antimony trichloride greater than 7N; the present invention passes the remaining part of the antimony trichloride gas into the reduction furnace, and reacts with the mixture of nitrogen and hydrogen from the bottom to obtain high-purity antimony greater than 7N, and the generated product gas is condensed and recovered. The method provided by the present invention can effectively control the uniformity and efficiency of the chlorination reaction by blowing multiple points of air at the top side bottom, improve the purity of the product antimony trichloride, obtain high-purity antimony trichloride and high-purity antimony, and greatly simplify the process of preparing antimony trichloride; and the non-condensable gas and product gas of the present invention can be recycled and reused, reducing the amount of reagents and reducing production costs.

[0060] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] The raw materials used in the embodiments of the present invention are:

[0062] Antimony particles: particle size is 1-1.5cm, purity is 99.1%, model is Shanxing brand No. 1 antimony ingot;

[0063] The protective gas is nitrogen, with a purity of ≥99.999%;

[0064] The purity of chlorine and hydrogen is ≥99.999%.

[0065] Example 1

[0066] A method for preparing high-purity antimony trichloride and high-purity antimony, comprising the following steps:

[0067] (1) putting antimony particles into a chlorination furnace, and then top blowing chlorine-containing gas, side blowing chlorine-containing gas and bottom blowing chlorine-containing gas, controlling the temperature to 900° C. for chlorination reaction to obtain antimony trichloride gas;

[0068] The flow rate of the top-blown chlorine-containing gas is 0.07 m / s, and the volume ratio of chlorine to nitrogen in the top-blown chlorine-containing gas is 39:61;

[0069] The flow rate of the side-blowing (center-blowing) chlorine-containing gas is 0.1 m / s, and the volume ratio of chlorine gas to nitrogen in the side-blowing chlorine-containing gas is 1:0.17; the side-blowing position is located in the middle position in the height direction of the chlorination furnace;

[0070] The flow rate of the bottom-blown chlorine-containing gas is 0.15 m / s, and the volume ratio of chlorine to nitrogen in the bottom-blown chlorine-containing gas is 2:98;

[0071] The molar ratio of chlorine gas to antimony particles in the top-blown chlorine-containing gas, the side-blown chlorine-containing gas and the bottom-blown chlorine-containing gas is 1:1.3;

[0072] (2) The antimony trichloride gas obtained in step (1) was added at a gas flow rate of 0.75 m 2 / m 3 / s into the condenser, the temperature of the condenser is selected to be 110℃, the condensing medium of the condenser is circulating water, and the flow rate of the condensing medium is 0.75m 3 / h, to obtain antimony trichloride mother liquor; condensing the antimony trichloride mother liquor at -10 to 10°C for 5h to obtain high-purity antimony trichloride, and the non-condensable gas is led out through a pipeline and recovered;

[0073] (3) The remaining antimony trichloride gas obtained in step (1) is introduced into the top of the reduction furnace, and hydrogen-containing gas (flow rate is 0.15 m / s) is blown at the bottom. 3 / h), controlling the temperature to 1100°C for reduction reaction to obtain high-purity antimony, and condensing the product gas at -10°C to recover liquid hydrogen chloride and uncondensed hydrogen;

[0074] The volume ratio of hydrogen to nitrogen in the hydrogen-containing gas is 1:29

[0075] The molar ratio of the antimony trichloride gas to the hydrogen in the hydrogen-containing gas is 1:1.5.

[0076] Test Example 1

[0077] (1) The test results of the antimony particles, high-purity antimony trichloride, purity of high-purity antimony and yield of antimony trichloride used in Example 1 are shown in Table 1.

[0078] Table 1 Test results of raw materials and products of the examples

[0079] Material parameters (purity) Numerical range Test Results Antimony particles 99.9～99.5 99.1 High purity chlorinated products 99.9999％～99.99999999％ 99.9999999％ High purity antimony trichloride ≥8N ≥8N Yield of antimony trichloride 93～98％ 96.5％ High purity antimony 99.9999％～99.99999999％ 99.9999999％ Yield of high purity antimony 90～95％ 93％

[0080] (2) The test results of the high-purity antimony prepared in Example 1 are shown in Table 2. The test method is: ISO / TS15338:2020, the test instrument is: glow discharge mass spectrometer, the entrusting unit is: Hunan Yuxiling New Materials Co., Ltd., and the sample number is: Sb023705.

[0081] Table 2 Test results of high purity antimony prepared in Example 1

[0082]

[0083] (3) The efficiency of recovery and utilization of non-condensable gas and product gas in Example 1 is shown in Table 3.

[0084] Table 3 Efficiency of recovery of non-condensable gas and product gas in Example 1

[0085] Material parameters Numerical range Test Results Hydrogen chloride recovery rate 90～95％ 92％ Hydrogen recovery rate 85～90％ 88％ Gas recycling rate ≥85％ 87％

[0086] It can be seen from the above results that the method provided by the present invention can obtain high-purity antimony trichloride and high-purity antimony (≥7N). This is because the present invention can effectively control the uniformity and efficiency of the chlorination reaction and improve the purity of the product antimony trichloride gas by blowing multiple points of air at the top side bottom. Therefore, the obtained antimony trichloride gas is sequentially condensed and crystallized to obtain high-purity antimony trichloride, and the high-purity antimony trichloride is obtained by reducing it in the bottom-blown hydrogen-containing gas, which greatly simplifies the process of preparing antimony trichloride; and the non-condensable gas and the product gas of the present invention can be recycled and reused, which reduces the amount of reagents used and reduces the production cost, and is suitable for industrial production.

[0087] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing high-purity antimony trichloride and high-purity antimony, comprising the following steps: (1) subjecting antimony particles to a chlorination reaction in a top-blown chlorine-containing gas, a side-blown chlorine-containing gas, and a bottom-blown chlorine-containing gas to obtain antimony trichloride gas; wherein the top-blown chlorine-containing gas, the side-blown chlorine-containing gas, and the bottom-blown chlorine-containing gas are mixed gases of chlorine gas and protective gas; (2) condensing and crystallizing the antimony trichloride gas obtained in step (1) to obtain high-purity antimony trichloride; (3) subjecting the remaining portion of the antimony trichloride gas obtained in step (1) to a reduction reaction in a bottom-blown hydrogen-containing gas to obtain high-purity antimony; the hydrogen-containing gas is a mixed gas of hydrogen and protective gas.

2. The method for preparing high-purity antimony trichloride and high-purity antimony according to claim 1, characterized in that: The purity of the antimony particles in step (1) is 99.9% to 99.91%.

3. The method for preparing high-purity antimony trichloride and high-purity antimony according to claim 1, characterized in that: The purity of the protective gas in step (1) and step (3) is independently ≥ 99.999%.

4. The method for preparing high-purity antimony trichloride and high-purity antimony according to claim 1, characterized in that: The flow rate of the top-blown chlorine-containing gas in step (1) is 0.05-0.1 m / s, and the volume ratio of chlorine gas to protective gas in the top-blown chlorine-containing gas is (25-39):(30-70).

5. The method for preparing high-purity antimony trichloride and high-purity antimony according to claim 1, characterized in that: The flow rate of the side-blown chlorine-containing gas in the step (1) is 0.08-0.15 m / s, and the volume ratio of chlorine gas to protective gas in the side-blown chlorine-containing gas is (0.8-1):(0.15-0.2).

6. The method for preparing high-purity antimony trichloride and high-purity antimony according to claim 1, characterized in that: The flow rate of the bottom-blown chlorine-containing gas in the step (1) is 0.1-0.3 m / s, and the volume ratio of chlorine gas to protective gas in the bottom-blown chlorine-containing gas is (2-5):(95-98).

7. The method for preparing high-purity antimony trichloride and high-purity antimony according to claim 1, characterized in that: In the step (1), the amount ratio of chlorine gas to antimony particles in the top-blown chlorine-containing gas, the side-blown chlorine-containing gas and the bottom-blown chlorine-containing gas is 1:(1.35-1.65).

8. The method for preparing high-purity antimony trichloride and high-purity antimony according to claim 1, characterized in that: The temperature of the chlorination reaction in step (1) is 750-1000°C.

9. The method for preparing high-purity antimony trichloride and high-purity antimony according to claim 1, characterized in that: In the step (3), the molar ratio of the antimony trichloride gas to the hydrogen in the hydrogen-containing gas is 1:(1.35-1.65).

10. The method for preparing high-purity antimony trichloride and high-purity antimony according to claim 1, characterized in that: The temperature of the reduction reaction in step (3) is 1000-1300°C.

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