Method for efficiently removing arsenic from antimony fire refining mixed base

Abstract

The invention discloses an efficient arsenic removal method for antimony fire refining mixed alkali. The method comprises the steps that antimony oxide and white coal are mixed and smelted to obtain antimony melt, and then after deslagging and lead removal are conducted in sequence, crude antimony liquid is obtained; the method comprises the following steps: blowing oxygen-enriched air into crude antimony liquid for the first time, stirring the antimony liquid to oxidize arsenic and simultaneously adjusting the temperature of the crude antimony liquid, then adding alkaline residues generated in the arsenic removal process, blowing oxygen-enriched air again after the alkaline residues are completely molten, discharging residues, then adding sodium carbonate, adding caustic soda flakes after the sodium carbonate is completely molten, blowing oxygen-enriched air for the third time, and discharging residues after the sodium carbonate is completely molten. And discharging alkaline residues to obtain the product. According to the method, the proportion of the arsenic content in the mixed alkali to the antimony liquid is strictly controlled, rapid arsenic enrichment is conducted on the antimony liquid with the high arsenic grade through the sodium carbonate, then deep arsenic removal is conducted on the antimony liquid with the low arsenic grade through the caustic soda flakes, the total time length of arsenic removal of refined antimony is greatly shortened, the arsenic removal efficiency is improved, and the arsenic removal efficiency is improved. And the usage amount of the arsenic removal agent and the loss amount of antimony are effectively reduced.

Description

Technical Field

[0001] The invention relates to a method for removing arsenic from antimony by refining, in particular to a method for efficiently removing arsenic by using mixed alkali in antimony pyrometallurgy, and belongs to the technical field of nonferrous metal smelting and impurity removal. Background Art

[0002] In the refining process of antimony, arsenic in crude antimony must be removed to obtain qualified refined antimony. In the current national standard for refined antimony, the arsenic content of the commonly used 1# refined antimony is required to be less than 0.05%. Therefore, for most antimony oxide products, deep arsenic removal is required to obtain qualified refined antimony.

[0003] Among the existing technologies, the commonly used arsenic removal methods are the soda ash arsenic removal method and the flake caustic soda arsenic removal method. The soda ash arsenic removal method involves blowing in compressed air under high temperature conditions, adding soda ash, and reacting multiple times to generate scum to remove arsenic deeply. However, this method has low efficiency in single arsenic removal reaction. For antimony liquid with high arsenic content, multiple arsenic removals are required, which brings about problems such as high fuel consumption, high reagent consumption, high scum yield and large antimony loss in the overall process, making it difficult to meet market requirements.

[0004] The process of arsenic removal by flake caustic soda is basically the same as that of arsenic removal by soda ash, which also involves blowing in compressed air under high temperature conditions, adding flake caustic soda, and reacting multiple times to generate scum to remove arsenic. Although this method has a high efficiency in single arsenic removal reaction, its total amount of arsenic removal is low, and multiple reactions are still required to achieve deep arsenic removal. However, the alkali slag formed by this method is not only viscous and difficult to discharge, but also has a high antimony grade. After multiple reactions, antimony loss will be further aggravated, resulting in a significant reduction in the overall antimony refining yield.

[0005] Therefore, the current market is in urgent need of an efficient pyrometallurgical arsenic removal method to improve the arsenic removal efficiency, save arsenic removal agents, and significantly reduce the antimony loss in the slag. Summary of the invention

[0006] In view of the problems existing in the prior art, the first object of the present invention is to provide an efficient arsenic removal method for antimony pyrorefining mixed alkali. The method is based on the synergistic effect between the steps. By strictly controlling the ratio of the arsenic content in the mixed alkali and the antimony liquid, the antimony liquid with a higher arsenic grade is firstly rapidly enriched with soda ash, and then the antimony liquid with a lower arsenic grade is deeply dearsenified with caustic soda flakes. Then all the alkali slag is removed together. This not only greatly shortens the total time for dearsenicization of refined antimony and improves the efficiency of dearsenicization, but also effectively reduces the amount of arsenic removal agent used and the amount of antimony loss. According to tests, compared with the prior art, the method has an arsenic content in the obtained refined antimony of less than 0.05%, a dearsenicization time shortened by more than 40%, a reduction in the amount of arsenic removal agent used by up to 51%, a reduction in the amount of antimony loss by up to 69%, and the obtained alkali slag can be returned to the dearsenicization process for recycling. While achieving efficient dearsenicization, the technical purpose of energy saving and emission reduction is also achieved.

[0007] To achieve the above technical objectives, the present invention provides an antimony pyrometallurgical refining mixed alkali efficient arsenic removal method, comprising:

[0008] Step S1, smelting antimony oxide and white coal to obtain antimony molten liquid, and then removing slag and lead in sequence to obtain crude antimony liquid;

[0009] Step S2, blowing oxygen-enriched air into the crude antimony liquid for the first time, stirring the antimony liquid to oxidize arsenic while adjusting the temperature of the crude antimony liquid;

[0010] Step S3, adding the alkaline slag produced in the arsenic removal process to the antimony liquid treated in step S2, and after the alkaline slag is completely melted, blowing in oxygen-enriched air again and performing slag discharge;

[0011] Step S4, first add soda ash to the antimony liquid treated in step S3, add caustic soda flakes after the soda ash is completely melted, then blow in oxygen-enriched air for the third time, and discharge the alkali residue to obtain;

[0012] The white coal accounts for 10-16% of the mass of antimony oxide; the amount of soda ash added is 1.8-5.2 times the total amount of arsenic in the antimony liquid after treatment in step S3; the amount of flake caustic soda added is 0.9-1.6 times the total amount of arsenic in the antimony liquid after treatment in step S3.

[0013] In the technical solution provided by the present invention, the addition amount and addition order of soda ash and caustic soda flakes need to be strictly controlled. In this solution, the role of soda ash is mainly to enrich arsenic in the antimony liquid while greatly reducing the grade of antimony in the alkali slag, and the role of caustic soda flakes is mainly to deeply remove arsenic from the antimony liquid. Therefore, when the arsenic grade in the antimony liquid is higher, the enrichment pressure of soda ash on arsenic is smaller, and the ratio of its addition amount to the total amount of arsenic is also lower. When the arsenic grade in the antimony liquid is higher, the deep arsenic removal pressure of caustic soda flakes is greater, and the ratio of its addition amount to the total amount of arsenic is also higher. In addition, since the alkali slag formed by caustic soda flakes has a high viscosity, if caustic soda flakes are added first, the dispersibility of soda ash will be greatly reduced, which will not only lead to an excessively high antimony grade in the alkali slag, but also make it difficult to enrich arsenic, and the technical purpose of the present invention cannot be achieved.

[0014] As a preferred solution, when the antimony oxide is bag antimony oxide, the mass proportion of white coal is 10-12%.

[0015] As a preferred solution, when the antimony oxide is surface-cooled antimony oxide, the proportion of white coal is 12-14%.

[0016] As a preferred solution, when the antimony oxide is fire cabinet antimony oxide, the proportion of white coal is 14-16%.

[0017] As a preferred solution, the additive in the lead removal process is a phosphate lead remover. Further preferably, the phosphate lead remover is monoammonium phosphate.

[0018] As a preferred solution, the lead content in the crude antimony liquid is ≤0.08%.

[0019] As a preferred solution, in step S3, the arsenic content in the antimony solution needs to be detected before adding the alkaline slag. When the arsenic content in the antimony solution is higher than 0.6%, alkaline slag with an arsenic grade of ≤5% is added.

[0020] As a preferred solution, the amount of alkali slag added is 4-6% of the mass of the antimony liquid.

[0021] As a preferred solution, in step S2, the temperature of the crude antimony solution is adjusted to 850-110°C.

[0022] As a preferred solution, the oxygen-enriched air is compressed air with a wind pressure of 0.15-0.20 MPa.

[0023] As a preferred solution, the time for the first blowing of oxygen-enriched air is 0.5 to 1 hour.

[0024] As a preferred solution, the time for re-bubbling oxygen-enriched air is 0.8 to 1.2 hours.

[0025] As a preferred solution, the time of the third blowing of oxygen-enriched air is proportional to the arsenic grade in the antimony liquid after the treatment in step S3.

[0026] As a preferred solution, the time for the third blowing of oxygen-enriched air is 0.5 to 1.5 hours.

[0027] As a preferred solution, the amount of soda ash added is inversely proportional to the arsenic grade in the antimony liquid after the treatment in step S3. When the arsenic grade in the antimony liquid is greater than 2%, the amount of soda ash added is 1.8 to 2.2 times the total amount of arsenic; when the arsenic grade in the antimony liquid is 1.3 to 2%, the amount of soda ash added is 2.2 to 2.7 times the total amount of arsenic in the antimony liquid; when the arsenic grade in the antimony liquid is 0.6 to 1.3%, the amount of soda ash added is 2.2 to 2.7 times the total amount of arsenic in the antimony liquid; when the arsenic grade in the antimony liquid is 0.3 to 0.6%, the amount of soda ash added is 2.7 to 4 times the total amount of arsenic in the antimony liquid; when the arsenic grade in the antimony liquid is less than 0.3%, the amount of soda ash added is 4 to 5.2 times the total amount of arsenic in the antimony liquid.

[0028] As a preferred solution, the amount of caustic soda flakes added is proportional to the arsenic grade in the antimony liquid after the treatment in step S3. When the arsenic grade in the antimony liquid is greater than 2%, the amount of caustic soda flakes added is 1.2 to 1.6 times the total arsenic in the antimony liquid; when the arsenic grade in the antimony liquid is 1 to 2%, the amount of caustic soda flakes added is 1.0 to 1.2 times the total arsenic in the antimony liquid; when the arsenic grade in the antimony liquid is less than 1%, the amount of caustic soda flakes added is 0.9 to 1.0 times the total arsenic in the antimony liquid.

[0029] Compared with the prior art, the beneficial technical effects of the technical solution of the present invention are:

[0030] The high-efficiency arsenic removal method provided by the present invention is based on the synergistic effect between the steps. By strictly controlling the ratio of the arsenic content in the mixed alkali and the antimony liquid, the antimony liquid with a higher arsenic grade is firstly quickly enriched with soda ash, and then the antimony liquid with a lower arsenic grade is deeply dearsenified with caustic soda flakes, and then all the alkali slag is removed together. This not only greatly shortens the total time for dearsenicization of refined antimony and improves the efficiency of dearsenicization, but also effectively reduces the amount of arsenic removal agent used and the amount of antimony loss. According to tests, compared with the prior art, the method has an arsenic content in the obtained refined antimony of less than 0.05%, a dearsenicization time shortened by more than 40%, a reduction in the amount of arsenic removal agent used by up to 51%, a reduction in the amount of antimony loss by up to 69%, and the obtained alkali slag can be returned to the dearsenicization process for recycling, thereby achieving efficient arsenic removal and the technical purpose of energy saving and emission reduction. DETAILED DESCRIPTION

[0031] The following examples are intended to illustrate the present invention rather than to further limit the present invention. The present invention can be implemented in any manner described in the summary of the invention.

[0032] Example 1

[0033] This embodiment provides a method for efficiently removing arsenic from antimony pyrometallurgical mixed alkali, which specifically includes:

[0034] The antimony oxide produced by the blast furnace is reduced and smelted by white coal, and about 75 tons of crude antimony is obtained after the slag is removed. The arsenic content of crude antimony is 1.81%. Monoammonium phosphate is added to remove lead, and the lead content is less than 0.072%. After the lead removal slag is removed, a blast pipe is added to the antimony liquid, and the wind pressure is controlled at 0.18MPa to stir the antimony liquid; the temperature is raised to about 950℃; 3.5 tons of alkaline slag with an arsenic grade of 3.2% and an antimony grade of 27.6% is added to the antimony liquid. After the alkaline slag is completely melted, the blast is performed for 1 hour, the furnace temperature is lowered to about 800℃, and the slag is removed. The slag produced this time weighs 2.68 tons, with an arsenic grade of 20.8%, an antimony grade of 3.6%, and an arsenic content of 1.22 in the antimony liquid. %; the temperature was raised to about 950℃ again, and 2.1t of soda ash was added; after the soda ash was completely melted, 1t of caustic soda flakes was added, and the temperature was cooled to about 800℃ after blasting for 40min, and the scum was removed. The scum produced this time weighed 4.36t, with an arsenic grade of 18.35%, an antimony grade of 11.6%, and 0.15% arsenic in the antimony liquid; the temperature was raised to about 950℃ again, 0.5t of soda ash was added, and after it was completely melted, 1t of caustic soda flakes was added, and the scum was removed after blasting for 30min. The scum produced this time weighed 2.2t, with an arsenic grade of 3.95%, an antimony grade of 20.3%, and 0.033% arsenic in the antimony liquid; the antimony liquid was released and cast into an ingot to obtain 1# refined antimony ingot. The total time for arsenic removal was 10.5h, 2.6t of soda ash and 2t of caustic soda flakes were consumed, 1.36t of arsenic was removed, 9.24t of alkali slag was produced, and 1.05t of antimony was lost in the slag.

[0035] Example 2

[0036] This embodiment provides a method for efficiently removing arsenic from antimony by pyrometallurgical refining mixed alkali, which specifically includes:

[0037] The antimony oxide produced by the blast furnace is reduced and smelted by white coal, and about 75 tons of crude antimony are obtained after the slag is removed. The arsenic content of crude antimony is 2.32%. Monoammonium phosphate is added to remove lead, and the lead content is 0.051%. After the lead removal slag is removed, a blast pipe is added to the antimony liquid, and the wind pressure is controlled at 0.2MPa to stir the antimony liquid; the temperature is raised to about 950℃; 3.5 tons of alkaline slag with an arsenic grade of 3.42% and an antimony grade of 22.3% are added to the antimony liquid. After the alkaline slag is completely melted, the blast is performed for 1 hour, the furnace temperature is lowered to about 800℃, and the slag is removed. The slag produced this time weighs 2.72 tons, with an arsenic grade of 22.82%, an antimony grade of 2.82%, and an arsenic content of 1.65% in the antimony liquid. ; The temperature is raised to about 950℃ again, and 3.3t of soda ash is added; after the soda ash is completely melted, 1.1t of flake caustic soda is added, and the temperature is lowered to about 800℃ after blasting for 40min, and the scum is scraped out. The scum produced this time weighs 6.2t, with an arsenic grade of 18.42%, an antimony grade of 10.82%, and arsenic content in the antimony liquid is 0.13%; The temperature is raised to about 950℃ again, 0.4t of soda ash is added, and after it is completely melted, 1t of flake caustic soda is added, and the scum is scraped out after blasting for 30min. The scum produced this time weighs 2.1t, with an arsenic grade of 3.54%, an antimony grade of 19.8%, and arsenic content in the antimony liquid is 0.030%; The antimony liquid is released for casting to obtain 1# refined antimony ingot. The total time for arsenic removal was 11.5 hours, consuming 3.7 tons of soda ash and 2.1 tons of caustic soda flakes, removing 1.84 tons of arsenic, producing 11.02 tons of alkali slag, and the antimony loss in the slag was 1.16 tons.

[0038] Example 3

[0039] This embodiment provides a method for efficiently removing arsenic from antimony by pyrometallurgical refining mixed alkali, which specifically includes:

[0040] The antimony oxide produced by the blast furnace is reduced and smelted by white coal, and about 75 tons of crude antimony is obtained after the slag is removed. The arsenic content of the crude antimony is 3.48%. Monoammonium phosphate is added to remove the lead, and the lead content is 0.048%; after removing the lead slag, a blast pipe is added to the antimony liquid, and the wind pressure is controlled to 0.17MPa to stir the antimony liquid; the temperature is raised to about 950℃; 4 tons of alkaline slag containing 2.92% arsenic and 20.4% antimony are added to the antimony liquid, and after the alkaline slag is completely melted, blast for 1h, reduce the furnace temperature to about 800℃, and remove the slag. The slag produced this time weighs 3.1t, with an arsenic grade of 21.66%, an antimony grade of 3.22%, and an arsenic content of 2.7% in the antimony liquid; the temperature is raised to about 900℃ again, and 3.8t of soda ash is added; after the soda ash is completely melted, 1.4t of flake caustic soda is added, and the blast is continued for 40m in, the temperature is lowered to about 800℃, and the slag is scraped out. The slag produced this time weighs 7.2t, with an arsenic grade of 20.2%, an antimony grade of 10.2%, and an arsenic content of 0.8% in the antimony liquid; the temperature is raised to about 950℃ again, 1.6t of soda ash is added, and 1t of flake caustic soda is added after complete melting, and the slag is scraped out after blasting for 30min. The slag produced this time is 3.8t, with an arsenic grade of 13.25%, an antimony grade of 21.8%, and an arsenic content of 0.13% in the antimony liquid; the temperature is raised to about 950℃ again, 0.5t of soda ash is added, and 1t of flake caustic soda is added after complete melting, and the slag is scraped out after blasting for 30min. The slag produced this time weighs 2.2t, with an arsenic grade of 3.22%, an antimony grade of 24.6%, and an arsenic content of 0.038% in the antimony liquid; the antimony liquid is released and cast into an ingot to obtain a 1# refined antimony ingot. The total time for arsenic removal was 15 hours, consuming 5.9 tons of soda ash and 2.4 tons of caustic soda flakes, removing 2.7 tons of arsenic, producing 16.3 tons of alkali slag, and the antimony loss in the slag was 2.20 tons.

[0041] Comparative Example 1

[0042] The antimony oxide produced by the blast furnace is reduced and smelted by white coal, and after the slag is removed, about 75 tons of crude antimony is obtained, and the arsenic content of the crude antimony is 2.42%. Monoammonium phosphate is added to remove lead, and the lead content is 0.062%; after removing the lead slag, a blast pipe is added to the antimony liquid, and the wind pressure is controlled to 0.18MPa to stir the antimony liquid; the temperature is raised to about 850℃; 2 tons of flake caustic soda is added to the antimony liquid, and the slag is removed after blasting for 2 hours. The slag produced this time weighs 2.9 tons, and the arsenic grade is 21.32%, the antimony grade is 20.3%, and the arsenic content in the antimony liquid is 1.6%; the temperature is raised to about 850℃ again, 2 tons of flake caustic soda is added, and the slag is removed after blasting for 2 hours. The slag produced this time weighs 2.8 tons, and the arsenic grade is 18.46 %, antimony grade was 23.4%, and arsenic in antimony liquid was 0.91%; 2t of flake caustic soda was added again, and the scum was scraped out after 2h of blowing. The scum produced this time was 3t, with arsenic grade of 14.6%, antimony grade of 26.77%, and arsenic in antimony liquid was 0.32%; 2t of flake caustic soda was added again, and the scum was scraped out after 2h of blowing. The scum produced this time was 3.2t, with arsenic grade of 5.2%, antimony grade of 28.42%, and arsenic in antimony liquid was 0.09%; 1t of flake caustic soda was added again, and the scum was scraped out after 1h of blowing. The scum produced this time weighed 1.6t, with arsenic grade of 3.22%, antimony grade of 28.56%, and arsenic in antimony liquid was 0.032%; the antimony liquid was discharged and cast into ingot to obtain 1# refined antimony ingot. The total time for arsenic removal was 20 hours, 0 tons of soda ash and 9 tons of flake caustic soda were consumed, 1.79 tons of arsenic were removed, 13.5 tons of alkali slag was produced, and the antimony loss in the slag was 3.41 tons.

[0043] It can be seen from Examples 1 to 3 that as the arsenic content in the antimony liquid increases, the amount of soda ash added gradually decreases, while the amount of soda ash flakes added gradually increases, the ratio of the total amount of arsenic removed to the amount of antimony loss is above 1.2, and the ratio of the total amount of alkali to the total amount of arsenic removed is below 3.4; in this method, the role of soda ash is mainly to enrich the arsenic in the antimony liquid while greatly reducing the grade of antimony in the alkali slag, while the role of soda ash flakes is mainly to deeply remove arsenic from the antimony liquid. Therefore, when the arsenic grade in the antimony liquid is higher, the enrichment pressure of soda ash on arsenic is smaller, and the ratio of its addition amount to the total amount of arsenic is also lower. When the arsenic grade in the antimony liquid is higher, the soda ash has a lower enrichment pressure on arsenic, and the ratio of its addition amount to the total amount of arsenic is also lower. The greater the deep arsenic removal pressure of caustic soda flakes, the higher the ratio of its addition amount to the total arsenic amount; in Comparative Example 1, only caustic soda flakes were used for deep arsenic removal, the ratio of the total arsenic removal amount to the antimony loss amount was 0.52, and the ratio of the total alkali amount to the total arsenic removal amount was 5.033, which shows that when a single alkali is used for antimony pyrorefining, compared with the method provided by the present invention, during the arsenic removal process, the antimony loss amount is greatly increased, the total alkali amount is greatly increased, and the total arsenic removal time is also greatly increased. Therefore, the method provided by the present invention achieves the technical purpose of saving arsenic removal agents, reducing the antimony loss in the slag and shortening the refining time while achieving efficient arsenic removal.

Claims

1. A method for efficiently removing arsenic by using mixed alkali for antimony pyrorefining, characterized in that: include: Step S1, smelting antimony oxide and white coal to obtain antimony molten liquid, and then removing slag and lead in sequence to obtain crude antimony liquid; Step S2, blowing oxygen-enriched air into the crude antimony liquid for the first time, stirring the antimony liquid to oxidize arsenic while adjusting the temperature of the crude antimony liquid; Step S3, adding the alkaline slag produced in the arsenic removal process to the antimony liquid treated in step S2, and after the alkaline slag is completely melted, blowing in oxygen-enriched air again and performing slag discharge; Step S4, first add soda ash to the antimony liquid treated in step S3, add caustic soda flakes after the soda ash is completely melted, then blow in oxygen-enriched air for the third time, and discharge the alkali residue to obtain; The white coal accounts for 10-16% of the mass of antimony oxide; the amount of soda ash added is 1.8-5.2 times the total amount of arsenic in the antimony liquid after treatment in step S3; the amount of flake caustic soda added is 0.9-1.6 times the total amount of arsenic in the antimony liquid after treatment in step S3.

2. The method for efficiently removing arsenic by mixed alkali from antimony pyrorefining according to claim 1, characterized in that: When the antimony oxide is bag antimony oxide, the mass proportion of white coal is 10-12%; when the antimony oxide is surface-cooled antimony oxide, the mass proportion of white coal is 12-14%; when the antimony oxide is fire cabinet antimony oxide, the mass proportion of white coal is 14-16%.

3. The method for efficiently removing arsenic by mixed alkali from antimony pyrorefining according to claim 1, characterized in that: The additive in the lead removal process is a phosphate lead removal agent; the lead content in the crude antimony liquid is ≤0.08%.

4. The method for efficiently removing arsenic by mixed alkali from antimony pyrorefining according to claim 1, characterized in that: In step S3, the arsenic content in the antimony liquid needs to be detected before adding the alkaline slag. When the arsenic content in the antimony liquid is higher than 0.6%, alkaline slag with an arsenic grade of ≤5% is added; the amount of the alkaline slag added is 4-6% of the mass of the antimony liquid.

5. The method for efficiently removing arsenic by mixed alkali from antimony pyrorefining according to claim 1, characterized in that: In the step S2, the temperature of the crude antimony liquid is adjusted to 850-110° C.; the oxygen-enriched air is compressed air with a wind pressure of 0.15-0.20 MPa.

6. The method for efficiently removing arsenic by mixed alkali from antimony pyrorefining according to claim 5, characterized in that: The time for the first blowing of oxygen-enriched air is 0.5-1 h; the time for the second blowing of oxygen-enriched air is 0.8-1.2 h.

7. The method for efficiently removing arsenic by mixed alkali from antimony pyrorefining according to claim 1, characterized in that: The time for the third blowing of oxygen-enriched air is proportional to the arsenic grade in the antimony liquid after treatment in step S3; the time for the third blowing of oxygen-enriched air is 0.5-1.5h.

8. The method for efficiently removing arsenic by mixed alkali from antimony pyrorefining according to claim 1, characterized in that: The amount of soda ash added is inversely proportional to the arsenic grade in the antimony liquid after the treatment in step S3. When the arsenic grade in the antimony liquid is greater than 2%, the amount of soda ash added is 1.8 to 2.2 times the total amount of arsenic; when the arsenic grade in the antimony liquid is 1.3 to 2%, the amount of soda ash added is 2.2 to 2.7 times the total amount of arsenic in the antimony liquid; when the arsenic grade in the antimony liquid is 0.6 to 1.3%, the amount of soda ash added is 2.2 to 2.7 times the total amount of arsenic in the antimony liquid; when the arsenic grade in the antimony liquid is 0.3 to 0.6%, the amount of soda ash added is 2.7 to 4 times the total amount of arsenic in the antimony liquid; when the arsenic grade in the antimony liquid is less than 0.3%, the amount of soda ash added is 4 to 5.2 times the total amount of arsenic in the antimony liquid.

9. The method for efficiently removing arsenic by mixed alkali from antimony pyrorefining according to claim 1, characterized in that: The amount of caustic soda added is proportional to the arsenic grade in the antimony liquid after the treatment in step S3. When the arsenic grade in the antimony liquid is greater than 2%, the amount of caustic soda added is 1.2 to 1.6 times the total amount of arsenic in the antimony liquid; when the arsenic grade in the antimony liquid is 1 to 2%, the amount of caustic soda added is 1.0 to 1.2 times the total amount of arsenic in the antimony liquid; when the arsenic grade in the antimony liquid is less than 1%, the amount of caustic soda added is 0.9 to 1.0 times the total amount of arsenic in the antimony liquid.