Method for measuring total carbon content in zinc hydrometallurgy electrolyte

Abstract

The invention discloses a method for measuring the total carbon content in a zinc hydrometallurgy electrolyte, which comprises the following steps of: 1, collecting a certain amount of zinc electrolyte by using a container, filtering to obtain filtrate, and taking a proper amount of filtrate to measure the acidity; step 2, transferring a proper amount of zinc electrolyte and adjusting the zinc electrolyte to be neutral to obtain a to-be-detected solution; step 3, freeze-drying the to-be-detected liquid to obtain a dry solid, and then transferring the dry solid into a sealed test sample preparation pulverizer to prepare a uniform and powdery to-be-detected sample; and 4, weighing a proper amount of the to-be-measured sample, introducing the to-be-measured sample into a high-frequency infrared carbon-sulfur instrument to measure the carbon content, and converting the carbon content of the zinc electrolyte according to the measurement result of the high-frequency infrared carbon-sulfur instrument. According to the method, the measurement accuracy can be improved, the method has many practical meanings in the aspects of stabilizing the quality of the zinc electrolyte, improving the production efficiency, reducing the electric energy loss, improving the quality of the zinc ingot and the like, and meanwhile, a new thought is provided for measuring low-content components in a high-body liquid sample.

Description

TECHNICAL FIELD

[0001] The application relates to a method for measuring the total carbon content in zinc electrolyte in a wet zinc leaching process. BACKGROUND

[0002] In the process of wet zinc leaching, the electrolyte required for the zinc electrolytic deposition process must be a relatively pure zinc sulfate solution to obtain high production efficiency. However, in actual production, the addition of various auxiliary materials such as gelatin and tartaric acid often causes a certain content of organic matter in the zinc electrolyte, which in turn affects the deposition efficiency of the finished zinc, reduces the current efficiency, and significantly increases the electrolysis energy consumption. In addition, the presence of organic matter in the electrolyte also easily causes a large amount of foam to be generated in the electrolytic tank during electrolysis, the zinc surface is reverse-solubilized and burned, and the deposited zinc sheet is loose and soft, which is not conducive to the subsequent stripping of the zinc sheet, causing waste of labor costs. Therefore, it is of great practical significance to measure the content of organic matter in the zinc sulfate electrolyte before zinc electrolytic deposition in order to improve the production efficiency and reduce the power consumption.

[0003] At present, the industry mainly uses total organic carbon (TOC) analyzers to measure the carbon content in the liquid sample to characterize the content of organic matter in the zinc electrolyte. Most of the organic matter in the sample can be oxidized and combusted at a high temperature of 680 DEG C to generate carbon dioxide, which is then absorbed and detected by the detection pool. However, there may still be a small number of organic matter that is not completely oxidized. In order to verify this point, a certain amount of high-molecular organic matter is added to the zinc electrolyte in the wet zinc leaching process, and the TOC analyzer is used for measurement. The measurement result is much lower than the total amount of the added organic matter, thereby suspecting that the organic matter cannot be completely oxidized and decomposed into carbon dioxide at a temperature of 680 DEG C, resulting in a low detection result. At the same time, during the detection process, the precipitation of part of the zinc sulfate and other salt crystals can wrap part of the sample, which is not completely combusted and oxidized and is also easy to cause the blockage of the combustion tube. In addition, the total organic carbon (TOC) analyzer lacks a corresponding sulfur absorption pool. The sulfur in the sample can enter the carbon detection pool together with the carbon dioxide, which can easily corrode the carbon detection pool and shorten the service life of the equipment. Therefore, it is urgent to develop a new and efficient analysis and detection method to improve the accuracy of the total carbon content detection of the zinc electrolyte.

[0004] The vacuum freeze dryer and the high-frequency infrared carbon and sulfur analyzer can realize the conversion from a liquid sample to a solid sample while maintaining the original components of the material. The high-frequency infrared carbon and sulfur analyzer can quickly and effectively detect the total carbon content of the solid sample, and its combustion temperature can be as high as 1300 DEG C, which can oxidize and decompose most of the organic matter, making the analysis result more accurate and reliable. SUMMARY

[0005] To address the aforementioned problems, the purpose of this invention is to provide a more effective new method for determining total carbon content, characterized by low detection limits, minimal matrix interference, and high detection accuracy. This method also offers a new approach for determining low-content components in high-volume bodily liquid samples.

[0006] The technical solution of this invention is: a method for determining the total carbon content in a wet zinc smelting electrolyte, the method comprising the following steps: S10. Collect a certain amount of zinc electrolyte in a container, take an appropriate amount of zinc electrolyte and filter it dry to obtain filtrate, and take an appropriate amount of filtrate to determine the acidity. S20. Take an appropriate amount of zinc electrolyte, and according to the acidity measured in the filtrate, add an equal amount of sodium hydroxide to adjust the zinc electrolyte to neutral to obtain the test solution; S30. Transfer the test liquid to a freeze dryer, so that the water in the test liquid evaporates directly into water vapor under vacuum conditions to obtain a dry solid. Transfer the dry solid into a sealed test sample preparation pulverizer to make a uniform, powdered test sample. S40. Weigh an appropriate amount of the sample to be tested, introduce it into a high-frequency infrared carbon-sulfur analyzer to determine the carbon content, and calculate the carbon content of the zinc electrolyte based on the measurement results of the high-frequency infrared carbon-sulfur analyzer.

[0007] Furthermore, the specific process of S10 is as follows: S101. Collect zinc electrolyte using a 2500mL capped plastic or glass container; S102. Transfer an appropriate amount of zinc electrolyte and filter it through rapid filter paper and a funnel into a dry 100mL beaker to obtain the filtrate; S103. Use a 2 mL pipette to transfer the filtrate into a 250 mL conical beaker, add 30 mL of EDTA-Ca masking agent, blow with water, add 2 drops of methyl red-methylene blue mixed indicator, and titrate with 0.25 mol / L sodium hydroxide standard titration solution until the endpoint is gray-green.

[0008] The method for determining the total carbon content in the wet zinc smelting electrolyte is characterized by the following preparation method for the methyl red-methylene blue mixed indicator: weigh 0.2 g of methyl red and dissolve it in 100 mL of water, dissolve 0.1 g of methylene blue in 100 mL of anhydrous ethanol, and mix the two solutions in equal volumes.

[0009] The method for determining the total carbon content in the wet zinc smelting electrolyte is characterized by the following preparation method for the EDTA-Ca masking agent: Weigh 100g of Na2EDTA and dissolve it in 900mL of water, dissolve 100g of calcium chloride in 900mL of water, mix the two solutions in equal volumes, add 10 drops of methyl red-methylene blue mixed indicator, weigh 23.79g of hydroxide solid to neutralize until it turns gray, and then titrate with 0.5mol / L sodium hydroxide standard solution until it turns green.

[0010] Furthermore, the specific process of S20 is as follows: S201. Weigh a pre-dried 500mL graduated cylinder, measure 500mL of electrolyte using the graduated cylinder, and then continue weighing using the same balance. S202. Transfer the electrolyte from the graduated cylinder to a 1000mL beaker, add an equal amount of sodium hydroxide according to the measured acidity, and stir with a glass rod until completely dissolved to obtain a neutral test solution.

[0011] Furthermore, the specific process of S30 is as follows: S301. Transfer the neutral test solution to the pre-weighed tray of the freeze dryer, rinse the beaker three times, add the washing liquid to the tray, mix well, and freeze-dry the neutral test solution by adjusting the freeze dryer program; S302. Take out the freeze-dried tray and weigh it on a balance; S303. Transfer the solid in the tray to a mortar and pestle, place it in a sample preparation and pulverizing machine for 3 minutes to prepare a uniform, powdered sample for testing.

[0012] Furthermore, the specific process of S40 is as follows: S401. Adjust the carbon channel of the high-frequency infrared carbon-sulfur analyzer and use a standard substance to confirm the instrument's state transition; S402. Weigh 0.1g of the sample to be tested and introduce it into a high-frequency infrared carbon-sulfur analyzer to determine the carbon content; S403. Based on the measurement data and weighing data from the high-frequency infrared carbon-sulfur analyzer, calculate the carbon content of the zinc electrolyte. The measurement results are calculated according to formulas (1) and (2): …………(1) …………(2) In the formula: m 3—The mass of the tray and the solid after freeze-drying, in grams; m 2—The mass of the empty tray before freeze-drying, in grams; m 1 — Total mass of graduated cylinder and neutral test solution, in g; m 0 — The mass of the empty graduated cylinder, in grams; ω —The result of the determination of total carbon in the sample, in % %. ω c —Determination of total carbon in zinc electrolyte, in % % V— Sampling volume of zinc electrolyte, in mL; ρ c —The result of the determination of total carbon in zinc electrolyte, in mg / L.

[0013] The beneficial effects of this invention are: 1. This invention develops a new method for determining the carbon content in wet zinc smelting electrolyte, which improves the accuracy of measurement and has many practical significance in stabilizing the quality of zinc electrolyte, improving production efficiency, reducing power consumption and improving the quality of zinc ingots. At the same time, it provides a new approach for determining low-content components in high-volume liquid samples. 2. The high-frequency infrared carbon-sulfur analyzer used in this invention can reach a temperature of 1300℃, which can completely burn and decompose organic matter, thus improving the accuracy of the measurement. 3. Because the zinc matrix and other metal impurities in the wet zinc smelting electrolyte are relatively high, they will form hydroxide precipitates with sodium hydroxide, which will affect the observation and judgment of the endpoint. Adding EDTA-Ca masking agent can facilitate the observation of the titration endpoint and make the acidity titration more accurate. 4. Because the electrolyte in wet zinc smelting contains a large amount of sulfuric acid matrix, it must be neutralized in step S20. If it is not neutralized, concentrated sulfuric acid will precipitate during the freeze-drying process, corroding the equipment and making subsequent tests impossible. If testing a new solution or other neutral high-matrix test solution, step S20 can be skipped. Attached Figure Description

[0014] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0015] 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.

[0016] like Figure 1 As shown, a method for determining the total carbon content in a wet zinc smelting electrolyte includes the following steps: S10. Collect a certain amount of zinc electrolyte in a container, take an appropriate amount of zinc electrolyte and filter it dry to obtain filtrate, and take an appropriate amount of filtrate to determine its acidity; the specific process is as follows: S101. Collect zinc electrolyte using a 500mL capped plastic or glass container; S102. Transfer the collected zinc electrolyte into a water bath, control the temperature at 60℃, and keep it at that temperature for 10 minutes. S103. Take an appropriate amount of zinc electrolyte and filter it through a rapid filter paper and funnel into a 100mL beaker to obtain the filtrate.

[0017] The method for determining the total carbon content in the wet zinc smelting electrolyte is characterized by the following preparation method for the methyl red-methylene blue mixed indicator: weigh 0.2 g of methyl red and dissolve it in 100 mL of water, dissolve 0.1 g of methylene blue in 100 mL of anhydrous ethanol, and mix the two solutions in equal volumes.

[0018] The method for determining the total carbon content in the wet zinc smelting electrolyte is characterized by the following preparation method for the EDTA-Ca masking agent: Weigh 100g of Na2EDTA and dissolve it in 900mL of water, dissolve 100g of calcium chloride in 900mL of water, mix the two solutions in equal volumes, add 10 drops of methyl red-methylene blue mixed indicator, weigh 23.79g of hydroxide solid to neutralize until it turns gray, and then titrate with 0.5mol / L sodium hydroxide standard solution until it turns green.

[0019] S20. Take an appropriate amount of zinc electrolyte, and adjust the zinc electrolyte to neutral by adding an equal amount of sodium hydroxide according to the acidity measured in the filtrate, to obtain the test solution; the specific process is as follows: S201. Weigh a pre-dried 500mL graduated cylinder, measure 500mL of electrolyte using the graduated cylinder, and then continue weighing using the same balance. S202. Transfer the electrolyte from the graduated cylinder to a 1000mL beaker, add an equal amount of sodium hydroxide according to the measured acidity, and stir with a glass rod until completely dissolved to obtain a neutral test solution.

[0020] S30. The test liquid is transferred to a freeze dryer, whereby the water in the test liquid evaporates directly into water vapor under vacuum conditions to obtain a dried solid. The dried solid is then transferred to a sealed laboratory sample preparation pulverizer to prepare a uniform, powdered test sample. The specific process is as follows: S301. Transfer the neutral test solution to the pre-weighed tray of the freeze dryer, rinse the beaker three times, add the washing liquid to the tray, mix well, and freeze-dry the neutral test solution by adjusting the freeze dryer program; S302. Take out the freeze-dried tray and weigh it on a balance; S303. Transfer the solid in the tray to a mortar and pestle, place it in a sample preparation and pulverizing machine for 3 minutes to prepare a uniform, powdered sample for testing.

[0021] S40. Weigh an appropriate amount of the sample to be tested, introduce it into a high-frequency infrared carbon-sulfur analyzer to determine the carbon content, and calculate the carbon content of the zinc electrolyte based on the results of the high-frequency infrared carbon-sulfur analyzer; the specific process is as follows: S401. Adjust the carbon channel of the high-frequency infrared carbon-sulfur analyzer and use a standard substance to confirm the instrument's state transition; S402. Weigh 0.1g of the sample to be tested and introduce it into a high-frequency infrared carbon-sulfur analyzer to determine the carbon content; S403. Based on the measurement data and weighing data from the high-frequency infrared carbon-sulfur analyzer, calculate the carbon content of the zinc electrolyte. The measurement results are calculated according to formulas (1) and (2): …………(1) …………(2) In the formula: m 3—The mass of the tray and the solid after freeze-drying, in grams; m 2—The mass of the empty tray before freeze-drying, in grams; m 1 — Total mass of the graduated cylinder and zinc electrolyte, in grams; m 0 — The mass of the empty graduated cylinder, in grams; ω —The result of the determination of total carbon in the sample, in % %. ω c —Determination of total carbon in zinc electrolyte, in % % V — Sampling volume of zinc electrolyte, in mL; ρ c —The result of the determination of total carbon in zinc electrolyte, in mg / L.

[0022] Example 1 Collect the wet zinc smelting electrolyte using a 2500mL capped plastic or glass container. A suitable amount of the wet zinc smelting electrolyte is filtered through rapid filter paper and a funnel into a 100mL beaker to obtain the filtrate. Using a 2mL pipette, transfer the filtrate into a 250mL conical beaker, add 30mL of EDTA-Ca masking agent, blow with water, and add 2 drops of methyl red-methylene blue mixed indicator. Titrate with 0.25mol / L sodium hydroxide standard titration solution until a gray-green endpoint is reached. Measure 500mL of the zinc electrolyte using a pre-weighed graduated cylinder, weigh it, and then transfer... The solution was transferred to a 1000mL beaker, and an appropriate amount of sodium hydroxide was added according to the measured acidity to adjust the zinc electrolyte to neutral, resulting in a neutral filtrate. The neutral filtrate was then transferred to a pre-weighed freeze dryer tray, and the freeze dryer was started to solidify the neutral filtrate. After solidification, the solid sample was removed, weighed, and transferred to a sample preparation pulverizer to prepare a uniform, powdered test sample. An appropriate amount of the test sample was directly weighed and introduced into a high-frequency infrared carbon-sulfur analyzer to determine the carbon content of the test sample. In this embodiment, 10 liquid samples from different stages and time periods of the wet zinc smelting process were selected. The analysis results are shown in Table 1. Table 1. Precision data of the test samples determined by the high-frequency infrared carbon-sulfur analyzer.

[0023] As shown in Table 1, the relative standard deviation (RSD) of the measurement is less than 2%, indicating that the homogeneity of the test sample after sample preparation is good. The data meets the precision requirements of GB / T 27417-2017 "Guideline for Conformity Assessment and Validation of Chemical Analysis Methods". Therefore, it can be seen that the high-frequency infrared carbon-sulfur analyzer has good reproducibility and high precision in measuring the liquid samples of zinc electrolysis processes such as frozen new liquid and circulating tank. Example 2

[0024] Collect the wet zinc smelting electrolyte using a 2500mL capped plastic or glass container. A suitable amount of the wet zinc smelting electrolyte is filtered through rapid filter paper and a funnel into a 100mL beaker to obtain the filtrate. Using a 2mL pipette, transfer the filtrate into a 250mL conical beaker, add 30mL of EDTA-Ca masking agent, flush with water, and add 2 drops of methyl red-methylene blue mixed indicator. Titrate with 0.25mol / L sodium hydroxide standard titration solution until a gray-green endpoint is reached. Using a pre-weighed graduated cylinder, measure a suitable amount of zinc electrolyte, weigh it, and transfer it to a beaker. Add an appropriate amount of hydroxide according to the determined acidity. Sodium hydroxide was used to adjust the zinc electrolyte to neutral, resulting in a neutral filtrate. An appropriate amount of carbon standard solution (500 mg / L) was added to a beaker based on the carbon content in the sample, and the mixture was stirred to obtain a homogenate. The homogenate was then transferred to a pre-weighed freeze dryer tray. The freeze dryer was started, and the homogenate was solidified. The solid sample was then weighed and transferred to a sample preparation pulverizer to prepare a uniform, powdered test sample. An appropriate amount of the test sample was weighed and introduced into a high-frequency infrared carbon-sulfur analyzer to determine the carbon content. Based on the high-frequency infrared carbon-sulfur analyzer data and the weighing data of the neutral liquid sample and the freeze-dried solid, the carbon content of the zinc electrolyte was calculated, and the recovery rate was also calculated.

[0025] The method for preparing the carbon standard solution (500 mg / L) described in this embodiment is as follows: After drying potassium hydrogen phthalate at 105℃~110℃ for 2 hours, weigh 1.06365 g and dissolve it in 100 mL of water. Transfer the above solution to a 1000 mL volumetric flask, dilute it with water to the mark, and shake well.

[0026] The liquid samples selected in this embodiment are the fresh liquid and the circulating tank of the hydrometallurgical zinc smelting process. 0.00 mL, 50 mL, and 100 mL of carbon standard solution (500 mg / L) were added sequentially to the fresh liquid, and 0.00 mL, 10 mL, and 20 mL of carbon standard solution (500 mg / L) were added sequentially to the circulating tank. The analytical results are shown in Tables 2 and 3. The spiked recovery rate was calculated according to formula (3): …………(3) In the formula: P— Spike recovery rate, in % ω 1 —The result of the determination of total carbon in the sample after adding carbon standard solution, in percentage (%). m 5—The mass of the tray and the solid after the test solution containing carbon standard solution is lyophilized, in grams; m 4—The mass of the empty tray before freeze-drying, in grams; —The average total carbon determination result in the test sample without the addition of carbon standard solution, in percentages (%). m 3—The mass of the tray and the solid after lyophilization of the test solution without the addition of carbon standard solution, in g; m 2 —The mass of the empty tray before freeze-drying, in grams; V 1 — Volume of carbon standard solution added, in mL; ρ —The mass concentration of the carbon standard solution, expressed in mg / L; 10 6 —Unit conversion: convert g to μg.

[0027] Table 2. Recovery data of fresh solution by freeze-drying and high-frequency infrared carbon-sulfur analyzer.

[0028] Table 3. Data on spiked recovery of circulating tank liquid samples determined by freeze-drying-high frequency infrared carbon-sulfur analyzer

[0029] Spike recovery rate is one way to evaluate the accuracy of a method. Generally, a range of 95% to 105% is required, but this can be relaxed to 90% to 110% for low-content components. The closer the spiked recovery rate is to 100%, the higher the accuracy of the method. As shown in Tables 2 and 3, the spiked recovery rate of the fresh solution ranges from 101.12% to 106.25%, and the spiked recovery rate of the circulating tank ranges from 97.64% to 102.29%, indicating accurate and reliable analysis.

[0030] Comparative Example 1 The total organic carbon (TOC) analyzer can be used to detect total organic carbon concentration (TOC), inorganic carbon concentration (IC), total carbon concentration (TC), and non-purgeable organic carbon concentration (NPOC). Following the instrument's operating procedure, zinc electrolyte was introduced into the instrument to analyze the total carbon concentration. A spiking recovery experiment was conducted using a 1000 mg / L carbon standard solution. The analytical results are shown in Table 4. The spiking recovery rate of this method was calculated using equation (4): ………… (4) In the formula: P— Spike recovery rate, in % ρ 1 —The total carbon concentration in the zinc electrolyte after adding the carbon standard solution, expressed in mg / L; — The average mass concentration of total carbon in the zinc electrolyte, in mg / L; V 1 — The volume of zinc electrolyte taken is in mL; V 2 — Volume of carbon standard solution added, in mL; ρ ρ ρ ρ ρ 2 — The mass concentration of the carbon standard solution, in mg / L.

[0031] Table 4 Total Organic Carbon Analyzer Measurement Data

[0032]

[0033]

[0034]

[0035] As shown in Table 4, the data consistency is poor, with the relative standard deviation (RSD) exceeding 34.75%, which is significantly higher than the 7.5% requirement of GB / T 27417-2017 "Guideline for Conformity Assessment and Validation of Chemical Analysis Methods". This indicates that the method is not suitable for determining high-matrix liquid samples. Through spike recovery experiments, the recoveries for a liquid sample + standard volume ratio (20 + 2) ranged from 57.01% to 152.76%, and the recoveries for a liquid sample + standard volume ratio (10 + 2) ranged from 38.26% to 97.28%, far from the standard requirement of 90% to 110%. This further proves that the total organic carbon analyzer is unsuitable for determining the total carbon content in hydrometallurgical zinc electrolytes.

[0036] 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.

[0037] 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 total carbon content in a wet zinc smelting electrolyte, characterized in that, The method includes the following steps: S10. Collect a certain amount of zinc electrolyte in a container, take an appropriate amount of zinc electrolyte and filter it dry to obtain filtrate, and take an appropriate amount of filtrate to determine the acidity. S20. Take an appropriate amount of zinc electrolyte, and according to the acidity measured in the filtrate, add an equal amount of sodium hydroxide to adjust the zinc electrolyte to neutral to obtain the test solution; S30. Transfer the test liquid to a freeze dryer, so that the water in the test liquid evaporates directly into water vapor under vacuum conditions to obtain a dry solid. Transfer the dry solid into a sealed test sample preparation pulverizer to make a uniform, powdered test sample. S40. Weigh an appropriate amount of the sample to be tested, introduce it into a high-frequency infrared carbon-sulfur analyzer to determine the carbon content, and calculate the carbon content of the zinc electrolyte based on the measurement results of the high-frequency infrared carbon-sulfur analyzer.

2. A method for determining the total carbon content in a wet zinc smelting electrolyte, characterized in that, If the test is performed on a fresh solution or other neutral high-matrix solution, the method includes the following steps: S10. Collect a certain amount of zinc electrolyte in a container, take an appropriate amount of zinc electrolyte and filter it dry to obtain filtrate, and take an appropriate amount of filtrate to determine the acidity. S30. Transfer the test liquid to a freeze dryer, so that the water in the test liquid evaporates directly into water vapor under vacuum conditions to obtain a dry solid. Transfer the dry solid into a sealed test sample preparation pulverizer to make a uniform, powdered test sample. S40. Weigh an appropriate amount of the sample to be tested, introduce it into a high-frequency infrared carbon-sulfur analyzer to determine the carbon content, and calculate the carbon content of the zinc electrolyte based on the measurement results of the high-frequency infrared carbon-sulfur analyzer.

3. The method for determining the total carbon content in the wet zinc smelting electrolyte according to claim 1 or 2, characterized in that, The specific process of S10 is as follows: S101. Collect zinc electrolyte using a 2500mL capped plastic or glass container; S102. Transfer an appropriate amount of zinc electrolyte and filter it through rapid filter paper and a funnel into a dry 100mL beaker to obtain the filtrate; S103. Use a 2 mL pipette to transfer the filtrate into a 250 mL conical beaker, add 30 mL of EDTA-Ca masking agent, blow with water, add 2 drops of methyl red-methylene blue mixed indicator, and titrate with 0.25 mol / L sodium hydroxide standard titration solution until the endpoint is gray-green.

4. The method for determining the total carbon content in the wet zinc smelting electrolyte according to claim 3, characterized in that, The preparation method of the methyl red-methylene blue mixed indicator is as follows: Weigh 0.2g of methyl red and dissolve it in 100mL of water, and dissolve 0.1g of methylene blue in 100mL of anhydrous ethanol. Mix the two solutions in equal volumes.

5. The method for determining the total carbon content in the wet zinc smelting electrolyte according to claim 3, characterized in that, The preparation method of the EDTA-Ca masking agent is as follows: Weigh 100g Na2EDTA and dissolve it in 900mL of water, dissolve 100g calcium chloride in 900mL of water, mix the two solutions in equal volumes, add 10 drops of methyl red-methylene blue mixed indicator, weigh 23.79g of hydroxide solid to neutralize until it turns gray, and then titrate it with 0.5mol / L sodium hydroxide standard solution until it turns green.

6. The method for determining the total carbon content in the wet zinc smelting electrolyte according to claim 1, characterized in that, The specific process of S20 is as follows: S201. Weigh a pre-dried 500mL graduated cylinder, measure 500mL of electrolyte using the graduated cylinder, and then continue weighing using the same balance. S202. Transfer the electrolyte from the graduated cylinder to a 1000mL beaker, add an equal amount of sodium hydroxide according to the measured acidity, and stir with a glass rod until completely dissolved to obtain a neutral test solution.

7. The method for determining the total carbon content in the wet zinc smelting electrolyte according to claim 1 or 2, characterized in that, The specific process of S30 is as follows: S301. Transfer the neutral test solution to the pre-weighed tray of the freeze dryer, rinse the beaker three times, add the washing liquid to the tray, mix well, and freeze-dry the neutral test solution by adjusting the freeze dryer program; S302. Take out the freeze-dried tray and weigh it on a balance; S303. Transfer the solid in the tray to a mortar and pestle, place it in a sample preparation and pulverizing machine for 3 minutes to prepare a uniform, powdered sample for testing.

8. The method for determining the total carbon content in the wet zinc smelting electrolyte according to claim 1 or 2, characterized in that, The specific process of S40 is as follows: S401. Adjust the carbon channel of the high-frequency infrared carbon-sulfur analyzer and use a standard substance to confirm the instrument status; S402. Weigh 0.1g of the sample to be tested and introduce it into a high-frequency infrared carbon-sulfur analyzer to determine the carbon content; S403. Calculate the carbon content of the zinc electrolyte based on the measurement and weighing data from the high-frequency infrared carbon-sulfur analyzer.

9. The method for determining the total carbon content in the wet zinc smelting electrolyte according to claim 1, 2, or 6, characterized in that, The measurement results are calculated according to formulas (1) and (2): …………(1) …………(2) In the formula: m 3—The mass of the tray and the solid after freeze-drying, in grams; m 2—The mass of the empty tray before freeze-drying, in grams; m 1 — Total mass of graduated cylinder and neutral test solution, in g; m 0 — The mass of the empty graduated cylinder, in grams; ω —The result of the determination of total carbon in the sample, in % %. ω c —Determination of total carbon in zinc electrolyte, in % % V — Sampling volume of zinc electrolyte, in mL; ρ c —The result of the determination of total carbon in zinc electrolyte, in mg / L.

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