Method for purifying and regenerating indium sulfate electrolytic waste liquid

Abstract

The invention discloses a purification and regeneration method of indium sulfate electrolytic waste liquid, and belongs to the technical field of resource reutilization, the method comprises the following steps: adjusting the pH value of the indium sulfate electrolytic waste liquid to 1-2 by using a sulfuric acid solution, when the pH value is 1-2, indium ions cannot be hydrolyzed, impurity ions (especially tin) can react with sulfur, the impurity ions are directionally removed, then extraction is performed, and the indium sulfate electrolytic waste liquid is obtained. According to the method, the solubility of impurity ions (especially zinc, cadmium, nickel and iron) in an extracting agent is larger than that of indium, selective impurity removal is conducted, finally, the pH is adjusted to be 0-2 again, indium ions are prevented from being hydrolyzed, activated carbon is added to adsorb organic matter, the regenerated indium sulfate electrolyte is obtained finally, and the impurity ions in the regenerated indium sulfate electrolyte are effectively removed. The regenerated indium sulfate electrolyte can be used for indium electrolysis.

Description

Technical Field

[0001] The present invention relates to the technical field of resource recycling, and particularly relates to a method for purifying and regenerating indium sulfate electrolytic waste liquid. Background Art

[0002] Indium, a rare and dispersed metal, is mainly applied to semiconductors, transparent conductive coatings, electronic devices, and organometallic compounds. The purity of indium metal directly affects the product performance. At present, in the production process of high-purity indium, indium sulfate electrolyte is used for electrolytic refining.

[0003] During the electrolysis process, with the extension of the electrolysis cycle, the dissolution of anode impurity metals (such as iron, copper, zinc, lead, etc.) in the electrolysis process leads to the enrichment of impurity ions. The presence of these impurities not only affects the electrolysis efficiency but also reduces the purity of the produced indium. Therefore, it is necessary to regularly purify or replace the indium sulfate electrolyte. However, the traditional methods for treating indium sulfate electrolyte often have problems such as low treatment efficiency, high energy consumption, and insufficient purity of the regenerated electrolyte. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method for purifying and regenerating indium sulfate electrolytic waste liquid, which can remove impurity ions in the indium sulfate electrolytic waste liquid.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A method for purifying and regenerating indium sulfate electrolytic waste liquid, comprising the following steps:

[0007] (1) Adjust the pH of the indium sulfate electrolytic waste liquid to 1 - 2 with sulfuric acid solution, introduce hydrogen sulfide gas, react, filter, and obtain a filtrate;

[0008] (2) Ultrasonically extract the filtrate with an extractant to obtain an extract;

[0009] (3) Adjust the pH of the extract to 0 - 2 with sulfuric acid solution, add activated carbon for adsorption, filter, and obtain a regenerated indium sulfate electrolyte.

[0010] The present invention adjusts the pH of the indium sulfate electrolytic waste liquid to 1 - 2 with sulfuric acid solution. At a pH of 1 - 2, indium ions will not hydrolyze, while impurity ions (especially tin) can react with sulfur to remove impurity ions directionally. Then, extraction is carried out. Utilizing the fact that the solubility of impurity ions (especially zinc, cadmium, nickel, iron) in the extractant is greater than that of indium, selective impurity removal is carried out. Finally, the pH is adjusted to 0 - 2 again to prevent indium ion hydrolysis, add activated carbon to adsorb organic substances, and finally obtain a regenerated indium sulfate electrolyte. The impurity ions in the regenerated indium sulfate electrolyte are effectively removed, and the regenerated indium sulfate electrolyte can be used for indium electrolysis.

[0011] As a preferred embodiment of the present invention, the feeding rate of the hydrogen sulfide gas is 0.2 - 0.3 L / min.

[0012] As a preferred embodiment of the present invention, the mass fraction of the sulfuric acid solution in step (1) is 80 - 98%.

[0013] As a preferred embodiment of the present invention, the molar concentration of the sulfuric acid solution in step (3) is 2 - 3 mol / L.

[0014] As a preferred embodiment of the present invention, the extractant comprises bis(2,4,4-trimethylpentyl)dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and sulfonated kerosene with a mass ratio of (15 - 35):(8 - 20):(45 - 77). In particular, when using the extractant composed of bis(2,4,4-trimethylpentyl)dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and sulfonated kerosene, under the synergistic effect of the three, impurity ions can be effectively removed.

[0015] As a preferred embodiment of the present invention, the extractant comprises bis(2,4,4-trimethylpentyl)dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and sulfonated kerosene with a mass ratio of (20 - 25):(12 - 15):(63 - 65). Especially when using bis(2,4,4-trimethylpentyl)dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and sulfonated kerosene with a mass ratio of (20 - 25):(12 - 15):(63 - 65), impurity ions can be further removed.

[0016] As a preferred embodiment of the present invention, the volume ratio of the filtrate to the extractant is 1:(3 - 6).

[0017] As a preferred embodiment of the present invention, the ultrasonic power is 20 - 40 W.

[0018] As a preferred embodiment of the present invention, the addition amount of the activated carbon is 50 - 100 g / L.

[0019] As a preferred embodiment of the present invention, the main element contents of the indium sulfate electrolytic waste liquid are: In 80 - 100 g / L, Sn 0.1 - 0.25 g / L, Zn 0.08 - 1.5 g / L, Cd 0.06 - 1.27 g / L, Ni 0.05 - 0.12 g / L, Fe 0.05 - 0.19 g / L.

[0020] As a preferred embodiment of the present invention, the reaction time in step (1) is 30 - 60 min.

[0021] As a preferred embodiment of the present invention, the extraction time in step (2) is 30 to 60 minutes.

[0022] As a preferred embodiment of the present invention, the adsorption time in step (3) is 1 to 2 hours.

[0023] The beneficial effects of the present invention are as follows: The indium sulfate electrolytic waste liquid of the present invention is adjusted to a pH of 1 to 2 with sulfuric acid solution. At a pH of 1 to 2, indium ions will not hydrolyze, while impurity ions (especially tin) can react with sulfur to remove impurity ions directionally. Then, extraction is carried out. By using the fact that the solubility of impurity ions (especially zinc, cadmium, nickel, and iron) in the extractant is greater than that of indium, selective impurity removal is carried out. Finally, the pH is adjusted to 0 to 2 again to prevent indium ion hydrolysis, activated carbon is added to adsorb organic matter, and finally a regenerated indium sulfate electrolyte is obtained. The impurity ions in the regenerated indium sulfate electrolyte are effectively removed, and the regenerated indium sulfate electrolyte can be used for indium electrolysis. Detailed implementation manners

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.

[0025] In the present application, for the technical features described in an open-ended manner, a closed technical solution composed of the listed features is included, as well as an open technical solution including the listed features.

[0026] In the present application, regarding the numerical range, unless otherwise specified, the above numerical range is considered continuous and includes the minimum and maximum values of this range, as well as each value between such minimum and maximum values. Further, when the range refers to an integer, each integer between the minimum and maximum values of this range is included. In addition, when multiple ranges are provided to describe features or characteristics, these ranges can be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all sub-ranges subsumed therein.

[0027] In the present application, there is no particular limitation on the specific dispersion and stirring treatment methods.

[0028] Unless otherwise specified, the component raw materials or instruments used in each embodiment and comparative example of the present invention are all commercially available raw materials or instruments, and the component raw materials used in each parallel experiment are the same.

[0029] The following embodiments are provided to facilitate the understanding of the present invention. These embodiments are provided not to limit the scope of the claims.

[0030] Example 1

[0031] A method for purifying and regenerating indium sulfate electrolytic waste liquid, comprising the following steps:

[0032] (1) Put the indium sulfate electrolytic waste liquid into a three-necked flask, adjust the pH of the indium sulfate electrolytic waste liquid to 2 with 98wt% sulfuric acid solution, introduce hydrogen sulfide gas at a flow rate of 0.2L / min, react for 50min, stand for 1h, filter to obtain a filtrate;

[0033] The main element contents of the indium sulfate electrolytic waste liquid are: In 85g / L, Sn 0.15g / L, Zn 1.5g / L, Cd 1.27g / L, Ni 0.11g / L, Fe 0.15g / L.

[0034] (2) Add the filtrate to the extractant, vibrate and extract for 40min under 40W ultrasonic to obtain an extract;

[0035] The extractant includes bis(2,4,4-trimethylpentyl) dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and sulfonated kerosene with a mass ratio of 20:15:65.

[0036] The volume ratio of the filtrate to the extractant is 1:4.

[0037] (3) Adjust the pH of the extract to 2 with 2mol / L sulfuric acid solution, add activated carbon at an addition amount of 80g / L and adsorb for 2h, filter to obtain a regenerated indium sulfate electrolyte solution.

[0038] Example 2

[0039] A method for purifying and regenerating indium sulfate electrolytic waste liquid, comprising the following steps:

[0040] (1) Put the indium sulfate electrolytic waste liquid into a three-necked flask, adjust the pH of the indium sulfate electrolytic waste liquid to 2 with 98wt% sulfuric acid solution, introduce hydrogen sulfide gas at a flow rate of 0.2L / min, react for 50min, stand for 1h, filter to obtain a filtrate;

[0041] The main element contents of the indium sulfate electrolytic waste liquid are: In 85g / L, Sn 0.15g / L, Zn 1.5g / L, Cd 1.27g / L, Ni 0.11g / L, Fe 0.15g / L.

[0042] (2) Add the filtrate to the extractant, vibrate and extract for 40min under 40W ultrasonic to obtain an extract;

[0043] The extractant includes bis(2,4,4-trimethylpentyl)dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester, and sulfonated kerosene with a mass ratio of 25:12:63.

[0044] The volume ratio of the filtrate to the extractant is 1:4.

[0045] (3) Adjust the pH of the extract to 2 with a 2 mol / L sulfuric acid solution, add activated carbon at an addition amount of 80 g / L for adsorption for 2 h, and filter to obtain the regenerated indium sulfate electrolyte.

[0046] Example 3

[0047] A method for purifying and regenerating indium sulfate electrolytic waste liquid includes the following steps:

[0048] (1) Put the indium sulfate electrolytic waste liquid into a three-necked flask, adjust the pH of the indium sulfate electrolytic waste liquid to 2 with a 98 wt% sulfuric acid solution, introduce hydrogen sulfide gas at a flow rate of 0.2 L / min, react for 50 min, stand for 1 h, and filter to obtain a filtrate;

[0049] The main element contents of the indium sulfate electrolytic waste liquid are: In 85 g / L, Sn 0.15 g / L, Zn 1.5 g / L, Cd 1.27 g / L, Ni 0.11 g / L, Fe 0.15 g / L.

[0050] (2) Add the filtrate to the extractant, vibrate and extract for 40 min under 40 W ultrasonic, to obtain an extract;

[0051] The extractant includes bis(2,4,4-trimethylpentyl)dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester, and sulfonated kerosene with a mass ratio of 15:8:77.

[0052] The volume ratio of the filtrate to the extractant is 1:4.

[0053] (3) Adjust the pH of the extract to 2 with a 2 mol / L sulfuric acid solution, add activated carbon at an addition amount of 80 g / L for adsorption for 2 h, and filter to obtain the regenerated indium sulfate electrolyte.

[0054] Example 4

[0055] A method for purifying and regenerating indium sulfate electrolytic waste liquid includes the following steps:

[0056] (1) Put the indium sulfate electrolytic waste liquid into a three-necked flask, adjust the pH of the indium sulfate electrolytic waste liquid to 2 with a 98 wt% sulfuric acid solution, introduce hydrogen sulfide gas at a flow rate of 0.2 L / min, react for 50 min, stand for 1 h, and filter to obtain a filtrate;

[0057] The main element contents of the indium sulfate electrolytic waste liquid are as follows: In 85 g / L, Sn 0.15 g / L, Zn 1.5 g / L, Cd 1.27 g / L, Ni 0.11 g / L, Fe 0.15 g / L.

[0058] (2) Add the filtrate to the extractant, and vibrate and extract for 40 min under 40 W ultrasonic to obtain an extract.

[0059] The extractant includes bis(2,4,4-trimethylpentyl) dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and sulfonated kerosene with a mass ratio of 35:20:45.

[0060] The volume ratio of the filtrate to the extractant is 1:4.

[0061] (3) Adjust the pH of the extract to 2 with a 2 mol / L sulfuric acid solution, add activated carbon at an addition amount of 80 g / L and adsorb for 2 h, then filter to obtain a regenerated indium sulfate electrolyte solution.

[0062] Example 5

[0063] A method for purifying and regenerating indium sulfate electrolytic waste liquid, comprising the following steps:

[0064] (1) Put the indium sulfate electrolytic waste liquid into a three-necked flask, adjust the pH of the indium sulfate electrolytic waste liquid to 1.5 with 98 wt% sulfuric acid solution, introduce hydrogen sulfide gas at a flow rate of 0.3 L / min, react for 50 min, let it stand for 1 h, and then filter to obtain a filtrate.

[0065] The main element contents of the indium sulfate electrolytic waste liquid are as follows: In 85 g / L, Sn 0.15 g / L, Zn 1.5 g / L, Cd 1.27 g / L, Ni 0.11 g / L, Fe 0.15 g / L.

[0066] (2) Add the filtrate to the extractant, and vibrate and extract for 40 min under 40 W ultrasonic to obtain an extract.

[0067] The extractant includes bis(2,4,4-trimethylpentyl) dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and sulfonated kerosene with a mass ratio of 20:15:65.

[0068] The volume ratio of the filtrate to the extractant is 1:4.

[0069] (3) Adjust the pH of the extract to 2 with a 2 mol / L sulfuric acid solution, add activated carbon at an addition amount of 80 g / L and adsorb for 2 h, then filter to obtain a regenerated indium sulfate electrolyte solution.

[0070] Comparative Example 1

[0071] A method for purifying and regenerating indium sulfate electrolytic waste liquid, comprising the following steps:

[0072] (1) Add the indium sulfate electrolytic waste liquid to the extractant, and vibrate and extract for 40 min under 40 W ultrasonic to obtain the extract;

[0073] The main element contents of the indium sulfate electrolytic waste liquid are: In 85 g / L, Sn 0.15 g / L, Zn 1.5 g / L, Cd 1.27 g / L, Ni 0.11 g / L, Fe 0.15 g / L.

[0074] The extractant includes bis(2,4,4-trimethylpentyl) dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and sulfonated kerosene with a mass ratio of 20:15:65.

[0075] The volume ratio of the indium sulfate electrolytic waste liquid to the extractant is 1:4.

[0076] (2) Adjust the pH of the extract to 2 with 2 mol / L sulfuric acid solution, add activated carbon for adsorption at an addition amount of 80 g / L for 2 h, and filter to obtain the regenerated indium sulfate electrolyte solution.

[0077] Comparative Example 2

[0078] A method for purifying and regenerating indium sulfate electrolytic waste liquid, comprising the following steps:

[0079] (1) Put the indium sulfate electrolytic waste liquid into a three-necked flask, adjust the pH of the indium sulfate electrolytic waste liquid to 2 with 98 wt% sulfuric acid solution, and filter to obtain the filtrate;

[0080] The main element contents of the indium sulfate electrolytic waste liquid are: In 85 g / L, Sn 0.15 g / L, Zn 1.5 g / L, Cd 1.27 g / L, Ni 0.11 g / L, Fe 0.15 g / L.

[0081] (2) Add the filtrate to the extractant, and vibrate and extract for 40 min under 40 W ultrasonic to obtain the extract;

[0082] The extractant includes bis(2,4,4-trimethylpentyl) dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and sulfonated kerosene with a mass ratio of 20:15:65.

[0083] The volume ratio of the filtrate to the extractant is 1:4.

[0084] (3) Adjust the pH of the extract to 2 with 2 mol / L sulfuric acid solution, add activated carbon for adsorption at an addition amount of 80 g / L for 2 h, and filter to obtain the regenerated indium sulfate electrolyte solution.

[0085] Comparative Example 3

[0086] A method for purifying and regenerating indium sulfate electrolytic waste liquid, comprising the following steps:

[0087] (1) Put the indium sulfate electrolytic waste liquid into a three-necked flask, adjust the pH of the indium sulfate electrolytic waste liquid to 3 with 98wt% sulfuric acid solution, introduce hydrogen sulfide gas at a flow rate of 0.2L / min, react for 50min, stand for 1h, filter to obtain a filtrate;

[0088] The main element contents of the indium sulfate electrolytic waste liquid are: In 85g / L, Sn 0.15g / L, Zn 1.5g / L, Cd 1.27g / L, Ni 0.11g / L, Fe 0.15g / L.

[0089] (2) Add the filtrate to an extractant, vibrate and extract for 40min under 40W ultrasonic to obtain an extract;

[0090] The extractant includes bis(2,4,4-trimethylpentyl) dithiophosphinic acid, 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and sulfonated kerosene with a mass ratio of 20:15:65.

[0091] The volume ratio of the filtrate to the extractant is 1:4.

[0092] (3) Adjust the pH of the extract to 2 with 2mol / L sulfuric acid solution, add activated carbon at an addition amount of 80g / L and adsorb for 2h, filter to obtain a regenerated indium sulfate electrolyte solution.

[0093] Comparative Example 4

[0094] A method for purifying and regenerating indium sulfate electrolytic waste liquid, comprising the following steps:

[0095] (1) Put the indium sulfate electrolytic waste liquid into a three-necked flask, adjust the pH of the indium sulfate electrolytic waste liquid to 2 with 98wt% sulfuric acid solution, introduce hydrogen sulfide gas at a flow rate of 0.2L / min, react for 50min, stand for 1h, filter to obtain a filtrate;

[0096] The main element contents of the indium sulfate electrolytic waste liquid are: In 85g / L, Sn 0.15g / L, Zn 1.5g / L, Cd 1.27g / L, Ni 0.11g / L, Fe 0.15g / L.

[0097] (2) Add the filtrate to an extractant, vibrate and extract for 40min under 40W ultrasonic to obtain an extract;

[0098] The extractant includes 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and sulfonated kerosene with a mass ratio of 35:65.

[0099] The volume ratio of the filtrate to the extractant is 1:4.

[0100] (3) Adjust the pH of the extract to 2 with a 2 mol / L sulfuric acid solution, add activated carbon at an addition amount of 80 g / L for adsorption for 2 h, and filter to obtain a regenerated indium sulfate electrolyte solution.

[0101] Comparative Example 5

[0102] A method for purifying and regenerating indium sulfate electrolytic waste liquid, comprising the following steps:

[0103] (1) Put the indium sulfate electrolytic waste liquid into a three-necked flask, adjust the pH of the indium sulfate electrolytic waste liquid to 2 with a 98 wt% sulfuric acid solution, introduce hydrogen sulfide gas at a flow rate of 0.2 L / min, react for 50 min, stand for 1 h, and filter to obtain a filtrate;

[0104] The main element contents of the indium sulfate electrolytic waste liquid are: In 85 g / L, Sn 0.15 g / L, Zn 1.5 g / L, Cd 1.27 g / L, Ni 0.11 g / L, Fe 0.15 g / L.

[0105] (2) Add the filtrate to the extractant, and vibrate and extract for 40 min under 40 W ultrasonic waves to obtain an extract;

[0106] The extractant includes bis(2,4,4-trimethylpentyl) dithiophosphinic acid and sulfonated kerosene with a mass ratio of 35:65.

[0107] The volume ratio of the filtrate to the extractant is 1:4.

[0108] (3) Adjust the pH of the extract to 2 with a 2 mol / L sulfuric acid solution, add activated carbon at an addition amount of 80 g / L for adsorption for 2 h, and filter to obtain a regenerated indium sulfate electrolyte solution.

[0109] Comparative Example 6

[0110] A method for purifying and regenerating indium sulfate electrolytic waste liquid, comprising the following steps:

[0111] (1) Put the indium sulfate electrolytic waste liquid into a three-necked flask, adjust the pH of the indium sulfate electrolytic waste liquid to 2 with a 98 wt% sulfuric acid solution, introduce hydrogen sulfide gas at a flow rate of 0.2 L / min, react for 50 min, stand for 1 h, and filter to obtain a filtrate;

[0112] The main element contents of the indium sulfate electrolytic waste liquid are: In 85 g / L, Sn 0.15 g / L, Zn 1.5 g / L, Cd 1.27 g / L, Ni 0.11 g / L, Fe 0.15 g / L.

[0113] (2) Add the filtrate to the extractant and vibrate and extract for 40 min under 40 W ultrasonic to obtain the extract.

[0114] The extractant includes tributyl phosphate and sulfonated kerosene with a mass ratio of 35:65.

[0115] The volume ratio of the filtrate to the extractant is 1:4.

[0116] (3) Adjust the pH of the extract to 2 with 2 mol / L sulfuric acid solution, add activated carbon at an addition amount of 80 g / L and adsorb for 2 h, then filter to obtain the regenerated indium sulfate electrolyte.

[0117] Test example

[0118] Use the ICP-OES method to test the concentrations of various elements in the regenerated indium sulfate electrolyte and calculate the indium recovery rate.

[0119] Table 1

[0120]

[0121]

[0122] As can be seen from Table 1, in the present invention, the pH of the indium sulfate electrolytic waste liquid is adjusted to 1-2 with sulfuric acid solution. At a pH of 1-2, indium ions will not hydrolyze, while impurity ions (especially tin) can react with sulfur to remove impurity ions directionally. Then extraction is carried out. By using the fact that the solubility of impurity ions (especially zinc, cadmium, nickel, and iron) in the extractant is greater than that of indium, selective impurity removal is carried out. Finally, the pH is adjusted to 0-2 again to prevent indium ion hydrolysis, activated carbon is added to adsorb organic substances, and finally the regenerated indium sulfate electrolyte is obtained. The impurity ions in the regenerated indium sulfate electrolyte are effectively removed, and the regenerated indium sulfate electrolyte can be used for indium electrolysis.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for purifying and regenerating indium sulfate electrolysis wastewater, characterized in that: The following steps are involved: (1) adjusting the pH of the indium sulfate electrolysis waste liquid to 1-2 with a sulfuric acid solution, introducing hydrogen sulfide gas, reacting, filtering, and obtaining a filtrate; (2) subjecting the filtrate to ultrasonic extraction using an extractant to obtain an extract; (3) The pH of the extract is adjusted to 0-2 with a sulfuric acid solution, activated carbon is added for adsorption, and the extract is filtered to obtain a regenerated indium sulfate electrolyte.

2. The method for purifying and regenerating indium sulfate electrolytic waste liquid according to claim 1, characterized in that: The amount of hydrogen sulfide gas introduced is 0.2-0.3 L / min.

3. The method for purifying and regenerating indium sulfate electrolytic waste liquid according to claim 1, characterized in that: The mass fraction of the sulfuric acid solution in step (1) is 80-98%.

4. The method for purifying and regenerating indium sulfate electrolytic waste liquid according to claim 1, characterized in that: The molar concentration of the sulfuric acid solution in step (3) is 2-3 mol / L.

5. The method for purifying and regenerating indium sulfate electrolytic waste liquid according to claim 1, characterized in that: The extractant comprises di(2,4,4-trimethylpentyl)dithiophosphinic acid, ethylhexyl mono-2-ethylhexyl phosphate and sulfonated kerosene in a mass ratio of (15-35):(8-20):(45-77).

6. The method for purifying and regenerating indium sulfate electrolytic waste liquid according to claim 1, characterized in that: The extractant comprises di(2,4,4-trimethylpentyl)dithiophosphinic acid, ethylhexyl mono-2-ethylhexyl phosphate and sulfonated kerosene in a mass ratio of (20-25):(12-15):(63-65).

7. The method for purifying and regenerating indium sulfate electrolytic waste liquid according to claim 1, characterized in that: The volume ratio of the filtrate to the extractant is 1:(3-6).

8. The method for purifying and regenerating indium sulfate electrolytic waste liquid according to claim 1, characterized in that: The ultrasonic power is 20-40W.

9. The method for purifying and regenerating indium sulfate electrolytic waste liquid according to claim 1, characterized in that: The added amount of the activated carbon is 50-100 g / L.

10. The method for purifying and regenerating indium sulfate electrolytic waste liquid according to claim 1, characterized in that: The main element contents of the indium sulfate electrolytic waste liquid are: In 80-100 g / L, Sn 0.1-0.25 g / L, Zn 0.08-1.5 g / L, Cd 0.06-1.27 g / L, Ni 0.05-0.12 g / L, and Fe 0.05-0.19 g / L.

Images