A method for determining the arsenic and antimony content in wet zinc smelting leachate

Abstract

This invention discloses a method for determining the arsenic and antimony content in hydrometallurgical zinc leaching solutions. Step one involves collecting a certain amount of zinc leaching solution in a container, heating the solution in a water bath, and filtering to obtain a filtrate. Step two involves taking a portion of the filtrate and adding saturated tartaric acid, concentrated hydrochloric acid, and thiourea-ascorbic acid in sequence, followed by heating to obtain the test solution. Step three involves introducing the test solution into an atomic fluorescence spectrometer for measurement, and calculating the arsenic and antimony content in the hydrometallurgical zinc leaching solution using the standard curve method. The beneficial effects of this invention are: shortening the analysis process, improving measurement accuracy, providing a detection guarantee for the precise control of arsenic and antimony content in leaching solutions in the hydrometallurgical zinc smelting industry, avoiding the use of toxic organic reagents during the detection process, improving environmental protection, reducing the risk of poisoning for operators, and enabling the simultaneous determination of both arsenic and antimony, saving half of the labor costs.

Description

Technical Field

[0001] This invention relates to a method for determining the arsenic and antimony content in the leaching solution of wet zinc smelting. Background Technology

[0002] Currently, over 85% of the world's zinc is produced through hydrometallurgical processes. This mainly includes four processes: roasting, leaching, purification, and electrowinning. During the leaching process, while the main valuable metals are leached from the raw materials, impurities such as arsenic and antimony also enter the solution. When the impurity content exceeds a certain limit, it will adversely affect zinc electrowinning, leading to the generation of arsine and antimony during electrolysis, seriously endangering the occupational health of workers. It can also cause zinc back-dissolution, and in severe cases, lead to plate burning and explosions on the electrowinning tank surface, severely restricting the efficiency of zinc smelting and causing significant waste. To avoid these consequences, the impurities in the supernatant after leaching and filtration must be treated to within the allowable range for electrowinning. Accurately measuring the arsenic and antimony content in the leaching solution is an essential part of guiding the production process. According to process requirements, the lower the impurity content of the leaching solution, the better the process control and the better the quality of the precipitated zinc. When the arsenic, antimony, and germanium content is >0.1 mg / L, it can produce visible burnt plates and significantly increase power consumption.

[0003] Currently, most foreign zinc smelting enterprises use hydride generation atomic absorption spectrometry, arsenic spot method, and colorimetric method. These methods have long processes, high labor costs, significant matrix interference, and use toxic organic reagents, making them extremely environmentally unfriendly. Furthermore, their accuracy is questionable. The main steps for arsenic detection involve reducing arsenic to arsine in sulfuric acid solution with zinc. After removing the hydrogen sulfide with lead acetate cotton, the arsine is absorbed by mercuric bromide paper strips, resulting in yellowish-brown spots of varying degrees. The length of the spots is compared with standard color levels to determine the arsenic content. The main steps for antimony detection involve reducing Sb(V) to Sb(III) in 6 mol / L hydrochloric acid solution with tin dichloride, then oxidizing Sb(III) to nascent Sb(V) with sodium nitrite, followed by SbCl6. - It forms a blue-green complex with brilliant green cations in 1.5 mol / L hydrochloric acid solution, and the maximum absorption wavelength is 640 nm after extraction with toluene. Both methods are lengthy, suffer from significant matrix interference, and use large amounts of toxic organic reagents, making them extremely environmentally unfriendly. Furthermore, their accuracy is questionable. Therefore, a rapid, safe, and accurate detection method is urgently needed.

[0004] Atomic fluorescence spectrometry, with its low detection limit and quantitation limit extended to 0.02 mg / L, provides superior detection for the control of arsenic and antimony in wet zinc refining, and offers more reliable guidance and control for the process of removing impurities. It also has strong anti-interference capabilities, uses simple reagents, has a short process, and can simultaneously determine arsenic and antimony, saving half of the labor costs. Summary of the Invention

[0005] To address the aforementioned problems, the purpose of this invention is to provide a more effective new method for determining arsenic and antimony content, which is simple to operate, has a short operation process, minimal matrix interference, high detection accuracy, and is environmentally friendly.

[0006] The technical solution of this invention is: a method for determining the arsenic and antimony content in wet zinc smelting leaching solution, the method comprising the following steps:

[0007] S10. Collect a certain amount of zinc leaching solution in a container, heat the zinc leaching solution in a water bath, filter it, and obtain filtrate;

[0008] S20. Take a portion of the filtrate, add saturated tartaric acid, concentrated hydrochloric acid, and thiourea-ascorbic acid in sequence, heat, and obtain the test solution;

[0009] S30. Introduce the test solution into an atomic fluorescence spectrometer for determination, and calculate the arsenic and antimony content of the wet zinc smelting leaching solution according to the standard curve method.

[0010] Furthermore, the specific process of S10 is as follows:

[0011] S101. Collect zinc leaching solution using a 500 mL capped plastic or glass container;

[0012] S102. Transfer the collected zinc leaching solution into a water bath, control the temperature at 60℃, and keep it at that temperature for 10 minutes.

[0013] S103. Pass the zinc leaching solution through rapid filter paper and a funnel to filter the constant-temperature zinc leaching solution into a 100mL beaker to obtain the filtrate;

[0014] Furthermore, the specific process of S20 is as follows:

[0015] S201. Use a 10 mL pipette to transfer the filtrate into a 100 mL beaker;

[0016] S202. Add 10 mL of saturated tartaric acid to a beaker, mix well, then add 10 mL of concentrated hydrochloric acid and 10 mL of thiourea-ascorbic acid mixture, and rinse the inner wall of the beaker with water to prepare the mixture; the thiourea-ascorbic acid mixture is an aqueous solution of thiourea and ascorbic acid with a concentration of 50 g / L.

[0017] S203. Place the mixture in an electric furnace, control the temperature at 120℃, react for 10 minutes, and then let it stand and cool to room temperature;

[0018] S204. Transfer the cooled mixture to a 100mL volumetric flask, make up to volume, mix well, and obtain the test solution.

[0019] Furthermore, the specific process of S30 is as follows:

[0020] S301. Transfer 0.00 mL, 1.00 mL, 2.00 mL, 4.00 mL, 6.00 mL, 8.00 mL, and 10.00 mL of the arsenic-antimony mixed standard solution into a set of 100 mL beakers; the concentration of arsenic and antimony in the arsenic-antimony mixed standard solution is 200 ng / mL.

[0021] S302. Add 20 mL of 37% concentrated hydrochloric acid and water in a 1:1 ratio to the beaker in sequence, along with 10 mL of thiourea-ascorbic acid mixture. Control the temperature at 120℃ and react for 10 min. Then remove the beaker and cool it to room temperature.

[0022] S303. Transfer the solution to a set of 100mL volumetric flasks, dilute with water to the mark, mix well, and prepare a standard solution of arsenic and antimony.

[0023] S304. Introduce the standard solution into the atomic fluorescence spectrometer using argon gas, with dilute hydrochloric acid (37% concentrated hydrochloric acid:water volume ratio of 1:9) as the carrier, and a potassium borohydride-potassium hydroxide solution as the reducing agent, and measure its fluorescence intensity.

[0024] S305. Plot a standard curve with the concentration of arsenic and antimony as the x-axis and the measured fluorescence intensity as the y-axis;

[0025] S306. Introduce the test solution into the atomic fluorescence spectrometer using argon gas. Use dilute hydrochloric acid with a mass fraction of 37% concentrated hydrochloric acid:water volume ratio of 1:9 as the carrier gas. Prepare a potassium borohydride-potassium hydroxide solution and measure its fluorescence intensity. Calculate the concentrations of arsenic and antimony using a standard curve.

[0026] The potassium borohydride-potassium hydroxide solution is an aqueous solution with potassium borohydride and potassium hydroxide concentrations of 20 g / L and 5 g / L, respectively.

[0027] The beneficial effects of this invention are: it shortens the analysis process, improves measurement accuracy, provides a detection guarantee for the precise control of arsenic and antimony content in the leaching solution of the hydrometallurgical zinc industry, avoids the use of toxic organic reagents during the detection process, improves the level of environmental protection, reduces the risk of poisoning to operators, and can determine both arsenic and antimony at the same time, saving half of the labor cost. Attached Figure Description

[0028] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0029] The present invention will be further described in detail below through embodiments, but the scope of the present invention is not limited to these embodiments.

[0030] like Figure 1As shown, a method for determining the arsenic and antimony content in a wet zinc smelting leaching solution includes the following steps:

[0031] S10. A certain amount of zinc leaching solution is collected using a container, and the zinc leaching solution is heated in a water bath and filtered to obtain filtrate; the specific process is as follows:

[0032] S101. Collect zinc leaching solution using a 500 mL capped plastic or glass container;

[0033] S102. Transfer the collected zinc leaching solution into a water bath, control the temperature at 60℃, and keep it at that temperature for 10 minutes.

[0034] S103. Pass the zinc leaching solution through rapid filter paper and a funnel to filter the constant-temperature zinc leaching solution into a 100mL beaker to obtain the filtrate;

[0035] S20. Take a portion of the filtrate, add saturated tartaric acid, concentrated hydrochloric acid, and thiourea-ascorbic acid in sequence, heat, and obtain the test solution; the specific process is as follows:

[0036] S201. Use a 10 mL pipette to transfer the filtrate into a 100 mL beaker;

[0037] S202. Add 10 mL of saturated tartaric acid to a beaker, mix well, then add 10 mL of concentrated hydrochloric acid and 10 mL of thiourea-ascorbic acid mixture, rinse the inner beaker wall with water to prepare the mixture; the thiourea-ascorbic acid mixture is an aqueous solution of thiourea and ascorbic acid with a mass fraction of 50 g / L.

[0038] S203. Place the mixture in an electric furnace, control the temperature at 120℃, react for 10 minutes, and then let it stand and cool to room temperature;

[0039] S204. Transfer the cooled mixture to a 100mL volumetric flask, make up to volume, mix well, and obtain the test solution;

[0040] S30. The test solution is introduced into an atomic fluorescence spectrometer for determination. The arsenic and antimony contents of the wet zinc smelting leaching solution are calculated according to the standard curve method. The specific process is as follows:

[0041] S301. Transfer 0.00 mL, 1.00 mL, 2.00 mL, 4.00 mL, 6.00 mL, 8.00 mL, and 10.00 mL of the arsenic-antimony mixed standard solution into a set of 100 mL beakers; the concentration of arsenic and antimony in the arsenic-antimony mixed standard solution is 200 ng / mL.

[0042] S302. Add 20 mL of 37% concentrated hydrochloric acid and water in a 1:1 ratio to the beaker in sequence, along with 10 mL of thiourea-ascorbic acid mixture. Control the temperature at 120℃ and react for 10 min. Then remove the beaker and cool it to room temperature.

[0043] S303. Transfer the solution to a set of 100mL volumetric flasks, dilute with water to the mark, mix well, and prepare a standard solution of arsenic and antimony.

[0044] S304. Introduce the standard solution into the atomic fluorescence spectrometer using argon gas, with dilute hydrochloric acid (37% concentrated hydrochloric acid:water volume ratio of 1:9) as the carrier, and a potassium borohydride-potassium hydroxide solution as the reducing agent, and measure its fluorescence intensity.

[0045] S305. Plot a standard curve with the concentration of arsenic and antimony as the x-axis and the measured fluorescence intensity as the y-axis;

[0046] S306. Introduce the test solution into the atomic fluorescence spectrometer using argon gas. Use dilute hydrochloric acid with a mass fraction of 37% concentrated hydrochloric acid:water volume ratio of 1:9 as the carrier gas. Prepare a potassium borohydride-potassium hydroxide solution and measure its fluorescence intensity. Calculate the concentrations of arsenic and antimony using a standard curve.

[0047] The potassium borohydride-potassium hydroxide solution is an aqueous solution with potassium borohydride and potassium hydroxide concentrations of 20 g / L and 5 g / L, respectively.

[0048] Example 1

[0049] Collect the wet zinc leaching solution using a 500mL covered plastic or glass container. Transfer the collected solution to a water bath and maintain the temperature at 60℃ for 10 minutes. Filter the solution through rapid filter paper and a funnel to obtain the filtrate. Use a 10mL pipette to transfer the filtrate to a 100mL beaker. Add 10mL of saturated tartaric acid and 10mL of... Concentrated hydrochloric acid and 10 mL of thiourea-ascorbic acid (50 g / L-50 g / L) were added, and the inner wall of the beaker was rinsed with water to prepare a mixture. The mixture was placed in an electric furnace at 120°C and reacted for 10 minutes. After cooling to room temperature, the cooled mixture was transferred to a 100 mL volumetric flask, diluted to volume, and mixed thoroughly to obtain the test solution. The test solution was then introduced into an atomic fluorescence spectrometer for determination. The arsenic and antimony content of the wet zinc smelting leachate was calculated using the standard curve method. To ensure the validity of the detection, a liquid sample with relatively high arsenic and antimony content was collected during the wet zinc smelting process, and a standard sample with a composition similar to the leachate was prepared. The analysis results are as follows:

[0050]

[0051]

[0052] Example 2

[0053] Collect the wet zinc leaching solution using a 500mL covered plastic or glass container. Transfer the collected solution to a water bath and maintain the temperature at 60℃ for 10 minutes. Filter the solution through rapid filter paper and a funnel to obtain the filtrate. Use a 10mL pipette to transfer the filtrate to a 100mL beaker. Add 10mL of saturated tartaric acid and 10mL of... Concentrated hydrochloric acid and 10 mL of thiourea-ascorbic acid (50 g / L-50 g / L) were added, and the inner wall of the beaker was rinsed with water to prepare a mixture. The mixture was placed in an electric furnace at 115°C and reacted for 10 minutes. After cooling to room temperature, the cooled mixture was transferred to a 100 mL volumetric flask, diluted to volume, and mixed thoroughly to obtain the test solution. The test solution was then introduced into an atomic fluorescence spectrometer for determination. The arsenic and antimony content of the wet zinc smelting leaching solution was calculated using the standard curve method. To ensure the validity of the detection, a liquid sample with relatively high arsenic and antimony content was collected during the wet zinc smelting process, and a standard sample with a composition similar to the leaching solution was prepared. The analysis results are as follows:

[0054] Sample Name Sample number Sb (mg / L) As (mg / L) leachate 230525-08:00 1.06 0.64 leachate 230523-08:00 1.57 2.03 leachate 230523-16:00 1.28 2.64 leachate 230524-08:00 0.75 1.40 leachate 230524-16:00 2.35 2.35 leachate 230522-08:00 0.77 1.26 0.100 mg / L standard / 0.098 0.099

[0055] Comparative Example 1

[0056] Collect the wet zinc leaching solution using a 500mL capped plastic or glass container. Transfer the collected wet zinc leaching solution into a water bath and maintain the temperature at 60℃ for 10 minutes. Filter the wet zinc leaching solution through rapid filter paper and a funnel, and then filter the constant-temperature solution into a 100mL beaker to obtain the filtrate. Use a 10mL pipette to transfer the filtrate into a 100mL beaker. Add 10mL of concentrated hydrochloric acid and 10mL of thiourea-ascorbic acid (50g / L-50g / L) to the beaker in sequence. Rinse the inner wall of the beaker with water to prepare a mixture. Place the mixture in an electric furnace and maintain the temperature at 120℃. After reacting for 10 minutes, allow it to cool to room temperature. Transfer the cooled mixture to a 100mL volumetric flask, make up to volume, and mix well to obtain the test solution. Introduce the test solution into an atomic fluorescence spectrometer for determination. Calculate the arsenic and antimony content of the wet zinc leaching solution according to the standard curve method. To ensure the validity of the test, a comparative sample of the leaching solution with relatively high arsenic and antimony content was collected during the hydrometallurgical zinc smelting process, and a standard sample with a composition similar to that of the leaching solution was prepared. The analytical results are as follows:

[0057] Sample Name Sample number Sb (mg / L) As (mg / L) leachate 230525-08:00 0.60 0.38 leachate 230523-08:00 0.89 1.24 leachate 230523-16:00 0.87 1.85 leachate 230524-08:00 0.58 1.12 leachate 230524-16:00 1.64 1.82 leachate 230522-08:00 0.60 0.38 0.100 mg / L standard / 0.069 0.075

[0058] The embodiments of the present invention have been described in detail above, but the content described is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the patent coverage of the present invention.

[0059] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for determining the arsenic and antimony content in a wet zinc smelting leachate, characterized in that, The method includes the following steps: S10. Collect a certain amount of zinc leaching solution in a container, heat the zinc leaching solution in a water bath, filter it, and obtain filtrate; S20. Take a portion of the filtrate, add saturated tartaric acid, concentrated hydrochloric acid, and thiourea-ascorbic acid in sequence, heat, and obtain the test solution; S30. Introduce the test solution into an atomic fluorescence spectrometer for determination, and calculate the arsenic and antimony content of the wet zinc smelting leaching solution according to the standard curve method; The specific process of S10 is as follows: S101. Collect zinc leaching solution using a 500 mL capped plastic or glass container; S102. Transfer the collected zinc leaching solution into a water bath, control the temperature at 60℃, and maintain the temperature for 10 minutes; S103. Pass the zinc leaching solution through rapid filter paper and a funnel to filter the constant-temperature zinc leaching solution into a 100mL beaker to obtain the filtrate; The specific process of S20 is as follows: S201. Use a 10 mL pipette to transfer the filtrate into a 100 mL beaker; S202. Add 10 mL of saturated tartaric acid to a beaker, mix well, then add 10 mL of concentrated hydrochloric acid and 10 mL of thiourea-ascorbic acid mixture, rinse the inner wall of the beaker with water to prepare the mixture. S203. Place the mixture in an electric furnace, control the temperature at 120℃, react for 10 minutes, and then let it stand and cool to room temperature; S204. Transfer the cooled mixture to a 100mL volumetric flask, make up to volume, mix well, and obtain the test solution; The specific process of S30 is as follows: S301. Transfer 0.00 mL, 1.00 mL, 2.00 mL, 4.00 mL, 6.00 mL, 8.00 mL, and 10.00 mL of the arsenic-antimony mixed standard solution into a set of 100 mL beakers, respectively; S302. Add 20 mL of 37% concentrated hydrochloric acid and water in a 1:1 ratio to the beaker in sequence, along with 10 mL of thiourea-ascorbic acid mixture. Control the temperature at 120℃ and react for 10 min. Then remove the beaker and cool it to room temperature. S303. Transfer the solution to a set of 100mL volumetric flasks, dilute with water to the mark, mix well, and prepare a standard solution of arsenic and antimony. S304. The standard solution was introduced into the atomic fluorescence spectrometer with argon gas. Dilute hydrochloric acid with a mass fraction of 37% concentrated hydrochloric acid:water volume ratio of 1:9 was used as the carrier, and potassium borohydride-potassium hydroxide solution was prepared as the reducing agent. The fluorescence intensity was then measured. S305. Plot a standard curve with the concentration of arsenic and antimony as the x-axis and the measured fluorescence intensity as the y-axis; S306. Introduce the test solution into the atomic fluorescence spectrometer using argon gas. Use dilute hydrochloric acid with a mass fraction of 37% concentrated hydrochloric acid:water volume ratio of 1:9 as the carrier gas. Prepare a potassium borohydride-potassium hydroxide solution and measure its fluorescence intensity. Calculate the concentrations of arsenic and antimony using a standard curve.

2. The method for determining the arsenic and antimony content in the wet zinc smelting leachate according to claim 1, characterized in that, The thiourea-ascorbic acid mixture is an aqueous solution of thiourea and ascorbic acid, both at a concentration of 50 g / L.

3. The method for determining the arsenic and antimony content in the wet zinc smelting leachate according to claim 1, characterized in that, The concentrations of arsenic and antimony in the arsenic-antimony mixed standard solutions were all 200 ng / mL.

4. The method for determining the arsenic and antimony content in the wet zinc smelting leachate according to claim 1, characterized in that, The potassium borohydride-potassium hydroxide solution is an aqueous solution with potassium borohydride and potassium hydroxide concentrations of 20 g / L and 5 g / L, respectively.

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