JP6990348B1 - How to recover and reuse nickel and phosphorus resources in electroless nickel plating waste liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for recovering and reusing nickel and phosphorus resources in electroless nickel plating waste liquid in the form of metallic nickel and iron phosphate. SOLUTION: The electroless nickel plating waste liquid is filtered by S1, a multi-stage security filter system, and S2, an electroless nickel plating waste liquid filtered by an anion unidirectional membrane electrodialysis system. To obtain a phosphorus concentrate, S3, electroless nickel plating waste liquid using a cation unidirectional membrane electrodialysis system, to obtain a nickel concentrate, S4, electro Treatment of phosphorus concentrate using Fenton technology, recovery and reuse of iron phosphate, S5, treatment of nickel concentrate using swirl flow electrolytic device, recovery and reuse of metallic nickel .. [Selection diagram] Fig. 1

Description

The present invention belongs to the technical field of industrial wastewater treatment and recycling, and specifically relates to a method for recovering and reusing nickel and phosphorus resources in an electroless nickel plating waste liquid.

Electroplating is a common process in the processing and manufacturing industry in China and is widely applied in fields such as mechanical, electronic and aerospace. Electroless nickel plating is an important field in the electroplating industry and is widely used worldwide due to its excellent corrosion resistance, wear resistance, solderability and uniform thickness of coating.
The electroless nickel plating industry is developing rapidly and at the same time raises the problem that a large amount of electroless nickel plating waste liquid needs to be treated. The electroless nickel plating waste liquid contains high concentrations of nickel and hypophosphite, and the content is several grams to several tens of grams per liter. Nickel, a heavy metal released into the body of water, has a clear toxic effect on aquatic organisms and can kill fish if the nickel ion concentration in the body of water exceeds 1.2 mg / L. Microorganisms in biochemical treatment methods cannot effectively utilize the hypophosphite in the effluent, and in most sewage treatment plants, such water treatment causes serious phosphorus excess discharge problems and large amounts of phosphorus. Is discharged into the water area and the pollution of the water quality becomes serious, and it is one of the eutrophication pollutants in the water area. According to Table 3 standards in China's Electroplated Contaminant Emission Standard (GB21900-2008), nickel permissible emission concentration is only 0.1 mg / L and total phosphorus permissible emission concentration is 0.5 m.
It is specified as g / L.
Nickel is a rare and expensive metal resource, and the price of nickel in the international market has been high in recent years. In 2020, the price of metallic nickel rose to 140,000 yuan / ton. At the same time, phosphorus resources are also one of the rare resources of China, and the Ministry of Land, Infrastructure, Transport and Tourism of China makes phosphorus resources one of the important minerals that cannot meet the needs of national economic development after 2010. In recent years, many scholars have been studying ways to extract increasingly valuable phosphorus resources from sludge generated in domestic sewage treatment plants. Arbitrary discharge of nickel and phosphorus in electroless nickel plating waste liquid without recycling inevitably wastes such rare and valuable resources.
Currently, the main treatment methods for electroless nickel plating waste liquid are chemical precipitation method, Fenton method, etc., and these methods require the addition of a large amount of sewage treatment chemicals, are costly, and at the same time, heavy metals in the waste liquid. , It is difficult to recover phosphorus resources, waste resources, generate a lot of sludge,
Secondary pollution is more likely to occur.

In consideration of the above problems, the present invention provides a method for recovering and reusing nickel and phosphorus resources in electroless nickel plating waste liquid, and specific technical solutions are as follows. The method of recovering and reusing nickel and phosphorus resources in electroless nickel plating waste liquid mainly includes the following steps:
S1, Waste liquid filtration The electroless nickel plating waste liquid is filtered by a multi-stage security filter system to remove particle impurities in the electroless nickel plating waste liquid.
S2, Separation and concentration of phosphorus in waste liquid Electroless nickel plating waste liquid filtered using a concentrated anion unidirectional membrane electrodialysis system is subjected to electrodialysis treatment, and hypophosphite in the electroless nickel plating waste liquid. Under the action of electric field force, the phosphite passes through the anion unidirectional membrane and enters the phosphorus concentrate pool, and phosphorus in the electroless nickel plating waste liquid is separated and concentrated to obtain a phosphorus concentrate.
S3, Separation of Nickel in Waste Liquid Using the concentrated cation unidirectional membrane electrodialysis system, the electroless nickel plating waste liquid treated in step S2 is subjected to electrodialysis treatment, and nickel ions in the electroless nickel plating waste liquid are performed. Under the action of electric field force, it passes through a cation unidirectional film and enters the nickel concentrate pool, and the nickel in the electroless nickel plating waste liquid is separated and concentrated to obtain a nickel concentrate.
S4, Post-treatment of Phosphorus Concentrate The phosphorus concentrate obtained in step S2 is treated using the electrophenon technology, and hypophosphoric acid in the phosphorus concentrate is treated under the action of OH produced by the electrofenton reaction. Salts and phosphite are oxidized to orthophosphate, which reacts with Fe ³⁺ in the electrofenton reaction system to form an iron phosphate crystal precipitate, resulting in iron phosphate crystals. Process the precipitate, collect it in iron phosphate and reuse it,
S5, Post-treatment of nickel concentrate The nickel concentrate obtained in step S3 is treated using a rotating electrolyzer, and the nickel ions in the nickel concentrate are reduced and deposited on the cathode to recover metallic nickel. And reuse it.

As one aspect of the present invention, in the filtration method of the multi-stage security filter system, the non-electrolytic nickel-plated waste liquid is introduced into the multi-stage security filter system, and the non-electrolytic nickel-plated waste liquid is contained in the non-electrolytic nickel-plated waste liquid by a plurality of sets of filtration tanks in the multi-stage security filter system. The particles are filtered and blocked in stages, the filtration opening diameter of the filtration tank gradually decreases from top to bottom, and after filtration, the particles obtained by filtration using a spray cleaning device at the top of the filtration tank. The surface of the non-electrolytic nickel plating waste liquid adhering to the filtered particles is separated and returned to the main body of the non-electrolytic nickel plating waste liquid. Separation according to size facilitates post-treatment, and at the same time uses a spray cleaning device to clean the electroless nickel-plated waste liquid adhering to the surface of the filtered particles, facilitating post-treatment of impurity particles. , Improves the recovery rate of nickel and phosphorus in non-electrolytic nickel plating waste liquid.

As one aspect of the present invention, the anion unidirectional membrane electrodialysis system is an anion unidirectional membrane for passing an electrolytic nickel-plated waste liquid, and a first anode electrode provided on both sides of the anion unidirectional membrane. A tank and a first cathode electrode tank are included, a phosphorus concentrate pool is provided between the first anode electrode tank and the anion unidirectional membrane, and the anion unidirectional membrane is hypophosphite and phosphite. If an electric field force is applied by utilizing the property of allowing salts to pass through, phosphorus in the electroless nickel plating waste liquid can be separated, and the separation cost is low and the efficiency is high.

As one aspect of the present invention, after operating the anion unidirectional membrane electrodialysis system for 5 to 7 days, the positions of the first anode electrode tank and the first cathode electrode tank are exchanged, and a phosphorus concentrate is simultaneously applied. The phosphorus concentrate pool between the first anode electrode tank and the anion unidirectional membrane was refilled and refilled.
By periodically changing the position of the electrode tank, both sides of the anion unidirectional film can be used, avoiding clogging due to long-term use of the anion unidirectional film, and cleaning the precipitate in the electrode tank when replacing the electrode tank. You can also do it.

As one aspect of the present invention, the cationic unidirectional membrane electrodialysis system is a cation unidirectional membrane through which a non-electrolytic nickel plating waste liquid is passed, and a second anode electrode tank provided on both sides of the cationic unidirectional membrane. , A second cathode electrode tank is included, a nickel concentrate pool is provided between the second cathode electrode tank and the cation unidirectional membrane, and the cation unidirectional membrane allows nickel ions to pass through. If an electric field force is applied, nickel in the electroless nickel plating waste liquid can be separated, and the separation cost is low and the efficiency is high.

As one aspect of the present invention, after operating the cationic unidirectional membrane electrodialysis system for 10 to 15 days, the positions of the second anode electrode tank and the second cathode electrode tank are exchanged, and at the same time, the nickel concentrate is prepared. Can be used on both sides of the cation unidirectional membrane by refilling the nickel concentrate pool between the second cathode electrode tank and the cation unidirectional membrane and periodically changing the position of the electrode tank. It is also possible to avoid clogging due to long-term use of the directional membrane and to clean the deposits in the electrode tank when replacing the electrode tank.

As one aspect of the present invention, the pH of the phosphorus concentrate obtained in step S2 is adjusted to 2.5 to 4 and the pH of the phosphorus concentrate is adjusted to 2.5 to 4 before the treatment of the electrofenton reaction system. If there,
The amount of OH produced by the electrofenton reaction system is large, and the oxidation efficiency of hypophosphite and phosphite in the phosphorus concentrate is high.

As one aspect of the present invention, the step of processing the iron phosphate crystal precipitate to obtain iron phosphate is described.
The iron phosphate crystal precipitate was washed with distilled water 3 to 5 times, and the washed iron phosphate crystal precipitate was washed 60 to 8 times.
Dry at 0 ° C. for 30-50 minutes and place the iron phosphate crystal precipitate in a sintering furnace to a purity of 99.9%.
The argon gas of No. 1 was used as a protective gas for the sintering furnace, the temperature in the sintering furnace was raised to 130 to 150 ° C at a heating rate of 5 ° C / min, held for 10 to 20 minutes, and then 10 ° C / The temperature in the sintering furnace is raised to 350 to 370 ° C at a heating rate of 30 to 370 ° C, and 20 to 3 under the condition of 350 to 370 ° C.
It involves heating for 0 minutes to obtain iron phosphate, the iron phosphate crystal precipitate contains water of crystallization, and in general, the treatment of the iron phosphate crystal precipitate contains two parts, dehydration and crystal conversion. Therefore, the processing step does not need to be divided into two steps under the condition that the heating rate and the high temperature processing time are controlled, and the efficiency is improved and the cost is saved.

As one aspect of the present invention, the phosphorus concentrate treated by the electrofenton technique is returned to step S2 to continue separation and concentration, and phosphorus in the phosphorus concentrate is recovered, and the number of returns is 1 to 3 times. The phosphorus concentration in the phosphorus concentrate is reduced to 9 by the electrofenton technology.
Reduced by 3% or more, the treated liquid contains a small amount of hypophosphite, phosphite, returned to step S2 to continue separation and concentration, further without affecting the entire process. Phosphorus can be recovered.

As one aspect of the present invention, the nickel concentrate treated by the rotary electrolysis is returned to step S3 to continue separation and concentration, and nickel in the nickel concentrate is recovered, and the number of returns is 1 to 5. The nickel concentration in the nickel concentrate is 90 due to the rotating electrolysis treatment.
The treated liquid contains nickel ions, which are reduced by% or more, and can be returned to step S3 for separation and concentration 1 to 5 times to further recover the nickel without affecting the entire process.

The present invention has the following beneficial effects. The method of recovering and reusing nickel and phosphorus resources in the electroless nickel plating waste liquid provided by the present invention is to multi-stage filter the electroless nickel plating waste liquid, separate and wash the impurity particles in the waste liquid, and filter the particles. Not only is the post-treatment easier, but the recovery rate of the waste liquid is also improved, and the waste liquid is treated stepwise using an anionic unidirectional membrane and a cation unidirectional membrane, and the electric field force and one of the unidirectional membranes are used. Phosphorus and nickel in the waste liquid are concentrated by directional passability, and the polarity of the electrode tank is periodically changed during the treatment process to extend the life of the ion unidirectional membrane, reduce the treatment cost, and reduce the treatment cost, metallic nickel and nickel acid. In the form of iron, it effectively recovers nickel-phosphorus resources in the waste liquid and reduces environmental pollution caused by the waste liquid. In a nutshell, the invention has advantages such as advanced method, complete process, high processing efficiency, low cost and so on.

It is a flowchart of the whole method of this invention. It is a structural drawing of the electrodialysis processing system of Example 1 of this invention. It is a structural schematic diagram of the electrodialysis treatment of Example 11 of this invention.

[Explanation of code]
1 Anion unidirectional membrane electrodialysis system 11 Anion unidirectional membrane 12 First anode electrode tank 13 First cathode electrode tank 14 Phosphorus concentrate pool 2 Cyanion unidirectional membrane electrodialysis system 21 Cyanion unidirectional membrane 22 2nd Electrode Electrode Tank 23 2nd Electrode Electrode Tank 24 Nickel Concentrate Pool 1a Bidirectional Film Assembly 11a Anion Exchange Film 12a Cryon Exchange Film 14a Phosphorus Concentrated Pool 24a Nickel Concentrated Pool 2a Electrode Electrode Tank 3a Cathode Electrode Tank

In order to facilitate the understanding of the technical solutions of the present invention, the present invention will be further interpreted and described below with reference to FIGS. 1 to 3 and specific examples, but the examples are the protection of the present invention. It does not limit the range.

Example 1: As shown in FIG. 1, a method of recovering and reusing nickel and phosphorus resources in electroless nickel plating waste liquid mainly includes the following steps:
S1, Waste liquid filtration The non-electrolytic nickel plating waste liquid is filtered by the multi-stage security filter system to remove particle impurities in the non-electrolytic nickel plating waste liquid, and the filtration method of the multi-stage security filter system is as follows: Was introduced into the multi-stage security filter system, and the particles in the electroless nickel-plated waste liquid were gradually filtered and blocked by multiple sets of filtration tanks in the multi-stage security filter system, and the filtration opening diameter of the filtration tank was directed from top to bottom. After filtration, the surface of the particles obtained by filtration is cleaned using a spray cleaning device at the top of the filtration tank, and the electroless nickel plating waste liquid adhering to the filtered particles is separated and electroless nickel plating. Return to the waste liquid body,
S2, Separation of phosphorus in waste liquid Phosphorus in the electroless nickel plating waste liquid is subjected to electrodialysis treatment using the concentrated anion unidirectional membrane electrodialysis system 1. Under the action of electric field force, the salt and phosphite pass through the anion unidirectional film 11 and enter the phosphorus concentrate pool 14, and the phosphorus in the electroless nickel plating waste liquid is separated and concentrated to obtain a phosphorus concentrate. ,
As shown in FIG. 2, in the anion unidirectional membrane electrodialysis system 1, the anion unidirectional membrane 11 through which the electroless nickel plating waste liquid passes, and the first anode electrodes provided on both sides of the anion unidirectional membrane 11 are provided. A tank 12 and a first cathode electrode tank 13 are included, and a phosphorus concentrate pool 14 is provided between the first anode electrode tank 12 and the anion unidirectional membrane 11.
After operating the anion unidirectional membrane electrodialysis system 1 for 6 days, the positions of the first anode electrode tank 12 and the first cathode electrode tank 13 are exchanged, and at the same time, the phosphorus concentrate is mixed with the first anode electrode tank 12. The phosphorus concentrate pool 14 between the anion unidirectional membranes 11 is refilled.
S3, Separation of Nickel in Waste Liquid Using the concentrated cation unidirectional membrane electrodialysis system 2, the electroless nickel plating waste liquid treated in step S2 is subjected to electrodialysis treatment, and nickel ions in the electroless nickel plating waste liquid are generated. Under the action of electric field force, it passes through the cation unidirectional film 21 and enters the nickel concentrate pool 24, and the nickel in the electroless nickel plating waste liquid is separated and concentrated to obtain a nickel concentrate.
As shown in FIG. 2, the cation unidirectional membrane electrodialysis system 2 has a cation unidirectional membrane 21 through which a non-electrolytic nickel plating waste liquid is passed, and a second anode electrode tank provided on both sides of the cation unidirectional membrane 21. 22, including the second cathode electrode tank 23, a nickel concentrate pool 24 is provided between the second cathode electrode tank 23 and the cation unidirectional membrane 21.
After operating the cation unidirectional membrane electrodialysis system 2 for 13 days, the second anode electrode tank 22
And the position of the second cathode electrode tank 23 are exchanged, and at the same time, the nickel concentrate is refilled in the nickel concentrate pool 24 between the second cathode electrode tank 23 and the cation unidirectional film 21.
S4, Post-treatment of phosphorus concentrate The pH of the phosphorus concentrate obtained in step S2 was adjusted to 3, the phosphorus concentrate was treated by the electro-Fenton technique, and under the action of OH produced by the electro-Fenton reaction.
Hypophosphate and phosphite in the phosphorus concentrate are oxidized to orthophosphate, and the orthophosphate reacts with Fe ³⁺ in the electrofenton reaction system to form an iron phosphate crystal precipitate. The obtained iron phosphate crystal precipitate is processed, recovered as iron phosphate and reused, and the phosphorus concentrate treated by the electrophenton technique is returned to step S2 to continue separation and concentration, and further phosphorus. Phosphoric acid in the concentrate is recovered and returned twice.
The step of processing the iron phosphate crystal precipitate to obtain iron phosphate is as follows: the iron phosphate crystal precipitate is washed 4 times with distilled water, and the washed iron phosphate crystal precipitate is dried at 70 ° C. for 40 minutes. , Iron phosphate crystal precipitate is placed in a sintering furnace, argon gas with a purity of 99.9% is used as a protective gas for the sintering furnace, and the temperature in the sintering furnace is raised to 140 at a heating rate of 5 ° C./min. After raising the temperature to ° C and holding for 15 minutes, the temperature in the precipitating furnace was raised to 350 ° C at a heating rate of 10 ° C / min, and 3 under 350 ° C conditions.
Heat for 0 minutes to obtain iron phosphate,
S5, Post-treatment of nickel concentrate The nickel concentrate obtained in step S3 is treated using a rotating electrolysis device, and the nickel ions in the nickel concentrate are reduced and deposited on the cathode, and the obtained metal is obtained. Nickel is recovered and reused, and the nickel concentrate that has been subjected to the cyclic electrolytic treatment is returned to step S3 to continue separation and concentration, and the nickel in the nickel concentrate is recovered, and the number of returns is three. ..

Example 2: Approximately the same as Example 1 except for the following:
S1, Waste liquid filtration Electroless nickel plating Waste liquid is filtered in one stage to remove particle impurities in the electroless nickel plating waste liquid.

Example 3: Approximately the same as Example 1 except for the following:
After operating the anion unidirectional membrane electrodialysis system 1 for 5 days, the positions of the first anode electrode tank 12 and the first cathode electrode tank 13 are exchanged, and at the same time, the phosphorus concentrate is mixed with the first anode electrode tank 12. The phosphorus concentrate pool 14 between the anion unidirectional membranes 11 is refilled.

Example 4: Approximately the same as Example 1 except for the following:
After operating the anion unidirectional membrane electrodialysis system 1 for 7 days, the positions of the first anode electrode tank 12 and the first cathode electrode tank 13 are exchanged, and at the same time, the phosphorus concentrate is mixed with the first anode electrode tank 12. The phosphorus concentrate pool 14 between the anion unidirectional membranes 11 is refilled.

Example 5: Approximately the same as Example 1 except for the following:
After running the cation unidirectional membrane electrodialysis system 2 for 10 days, the second anode electrode tank 22
And the position of the second cathode electrode tank 23 are exchanged, and at the same time, the nickel concentrate is refilled in the nickel concentrate pool 24 between the second cathode electrode tank 23 and the cation unidirectional film 21.

Example 6: Approximately the same as Example 1 except for the following:
After running the cation unidirectional membrane electrodialysis system 2 for 15 days, the second anode electrode tank 22
And the position of the second cathode electrode tank 23 are exchanged, and at the same time, the nickel concentrate is refilled in the nickel concentrate pool 24 between the second cathode electrode tank 23 and the cation unidirectional film 21.

Example 7: Approximately the same as Example 1 except for the following:
S4, Post-treatment of phosphorus concentrate The pH of the phosphorus concentrate obtained in step S2 is adjusted to 2.5, the phosphorus concentrate is treated by the electrofenton technique, and under the OH action produced by the electrofenton reaction, the phosphorus concentrate is treated. Hypophosphate and phosphite in the phosphorus concentrate are oxidized to orthophosphate, and the orthophosphate reacts with Fe ³⁺ in the electrofenton reaction system to form an iron phosphate crystal precipitate. Then, the obtained iron phosphate crystal precipitate was processed, recovered as iron phosphate and reused, and the phosphorus concentrate treated by the electrofenton technique was returned to step S2 to continue separation and concentration, and further. Phosphorus in the phosphorus concentrate is recovered and returned once.
The step of processing the iron phosphate crystal precipitate to obtain iron phosphate is as follows: the iron phosphate crystal precipitate is washed three times with distilled water, and the washed iron phosphate crystal precipitate is dried at 60 ° C. for 30 minutes. , Iron phosphate crystal precipitate is placed in a sintered furnace, argon gas with a purity of 99.9% is used as a protective gas for the sintered furnace, and the temperature in the sintered furnace is 130 at a heating rate of 5 ° C./min. After raising the temperature to ° C and holding for 10 minutes, the temperature in the precipitating furnace is raised to 360 ° C at a heating rate of 10 ° C / min, and 2 under 360 ° C conditions.
Heat for 5 minutes to obtain iron phosphate.

Example 8: Approximately the same as Example 1 except for the following:
S4, Post-treatment of phosphorus concentrate The pH of the phosphorus concentrate obtained in step S2 is adjusted to 4, the phosphorus concentrate is treated by the electrofenton technique, and the phosphorus concentrate is subjected to the OH action generated by the electrofenton reaction. Hypophosphate and phosphite in the liquid are oxidized to orthophosphate, and the orthophosphate reacts with Fe ³⁺ in the electrofenton reaction system to form an iron phosphate crystal precipitate. The obtained iron phosphate crystal precipitate is processed, recovered as iron phosphate and reused, and the phosphorus concentrate treated by the electrofenton technique is returned to step S2 to continue separation and concentration, and further phosphorus concentration. Phosphoric acid in the liquid is collected and returned 3 times.
The step of processing the iron phosphate crystal precipitate to obtain iron phosphate is as follows: the iron phosphate crystal precipitate is washed 5 times with distilled water, and the washed iron phosphate crystal precipitate is dried at 80 ° C. for 50 minutes. , Iron phosphate crystal precipitate is placed in a sintering furnace, argon gas with a purity of 99.9% is used as a protective gas for the sintering furnace, and the temperature in the sintering furnace is set to 150 at a heating rate of 5 ° C./min. The temperature was raised to 370 ° C., held for 20 minutes, and then the temperature in the precipitating furnace was raised to 370 ° C. at a heating rate of 10 ° C./min.
Heat for 0 minutes to obtain iron phosphate.

Example 9: Approximately the same as Example 1 except for the following:
S5, Post-treatment of nickel concentrate The nickel concentrate obtained in step S3 is treated using a rotating electrolysis device, and the nickel ions in the nickel concentrate are reduced and deposited on the cathode, and the obtained metal is obtained. Nickel is recovered and reused, and the nickel concentrate that has been subjected to the cyclic electrolytic treatment is returned to step S3 to continue separation and concentration, and the nickel in the nickel concentrate is recovered, and the number of returns is one. ..

Example 10: Approximately the same as Example 1 except for the following:
S5, Post-treatment of nickel concentrate The nickel concentrate obtained in step S3 is treated using a swirl-flow type electrolytic device, and the nickel ions in the nickel concentrate are reduced and deposited on the cathode, and the obtained metal is obtained. Nickel is recovered and reused, and the nickel concentrate that has been subjected to the cyclic electrolytic treatment is returned to step S3 to continue separation and concentration, and the nickel in the nickel concentrate is recovered, and the number of returns is 5 times. ..

Example 11: A method for recovering and reusing nickel and phosphorus resources in electroless nickel plating waste liquid mainly includes the following steps:
S1, Waste liquid filtration The non-electrolytic nickel plating waste liquid is filtered by the multi-stage security filter system to remove particle impurities in the non-electrolytic nickel plating waste liquid, and the filtration method of the multi-stage security filter system is as follows: Was introduced into the multi-stage security filter system, and the particles in the electroless nickel-plated waste liquid were gradually filtered and blocked by multiple sets of filtration tanks in the multi-stage security filter system, and the filtration opening diameter of the filtration tank was directed from top to bottom. After filtration, the surface of the particles obtained by filtration is cleaned using a spray cleaning device at the top of the filtration tank, and the electroless nickel plating waste liquid adhering to the filtered particles is separated and electroless nickel plating. Return to the waste liquid body,
S2, phosphorus and nickel in the waste liquid are separated and concentrated synchronously. As shown in FIG. 3, the synchronous electrodialysis system is provided on both sides of the bidirectional membrane set 1a and the bidirectional membrane set 1a through which the electroless nickel plating waste liquid is passed. Anode electrode tank 2a, cathode electrode tank 3
Including a
The side of the bidirectional membrane assembly 1a near the anode electrode tank 2a is the anion exchange membrane 11a, and a phosphorus concentration pool 14a is provided between the anion exchange membrane 11a and the anode electrode tank 2a. Anion exchange membrane 11 under the action of sulphate and sulphate under the action of electric field force
It passes through a and enters the phosphorus concentrate 14a, and the phosphorus in the electroless nickel plating waste liquid is separated and concentrated to obtain a phosphorus concentrate.
The side of the bidirectional film assembly 1a close to the cathode electrode tank 3a is the cation exchange film 12a, and a nickel concentration pool 24a is provided between the cation exchange film 12a and the cathode electrode tank 3a, and nickel in the non-electrolytic nickel plating waste liquid is provided. Under the action of electric field force, ions pass through the cation exchange film 12a and enter the nickel concentration pool 14a, and the nickel in the non-electrolytic nickel plating waste liquid is separated and concentrated to obtain a nickel concentrate.
S3, Post-treatment of phosphorus concentrate The pH of the phosphorus concentrate obtained in step S2 is adjusted to 3, the phosphorus concentrate is treated by the electrofenton technique, and the phosphorus concentrate is subjected to the OH action generated by the electrofenton reaction. Hypophosphate and phosphite in the liquid are oxidized to orthophosphate, and the orthophosphate reacts with Fe ³⁺ in the electrofenton reaction system to form an iron phosphate crystal precipitate. The obtained iron phosphate crystal precipitate is processed, recovered as iron phosphate and reused, and the phosphorus concentrate treated with electrofenton technology is returned to step S2 to continue separation and concentration, and further phosphorus concentrate. The phosphorus inside is collected and returned twice.
The step of processing the iron phosphate crystal precipitate to obtain iron phosphate is as follows: the iron phosphate crystal precipitate is washed 4 times with distilled water, and the washed iron phosphate crystal precipitate is dried at 70 ° C. for 40 minutes. , Iron phosphate crystal precipitate is placed in a sintering furnace, argon gas with a purity of 99.9% is used as a protective gas for the sintering furnace, and the temperature in the sintering furnace is raised to 140 at a heating rate of 5 ° C./min. After raising the temperature to ° C and holding for 15 minutes, the temperature in the precipitating furnace was raised to 350 ° C at a heating rate of 10 ° C / min, and 3 under 350 ° C conditions.
Heat for 0 minutes to obtain iron phosphate.
S4, Post-treatment of nickel concentrate The nickel concentrate obtained in step S2 is treated using a swirl-flow type electrolytic device, and the nickel ions in the nickel concentrate are reduced and deposited on the cathode, and the obtained metal is obtained. Nickel is recovered and reused, and the nickel concentrate that has been subjected to the cyclic electrolytic treatment is returned to step S2 to continue separation and concentration, and the nickel in the nickel concentrate is recovered, and the number of returns is three. ..

Experimental Example 1: Studying the effect of the multi-stage filtration security system on the recycling of nickel and phosphorus resources The electroless nickel plating waste liquid was treated by the methods of Example 1 and Example 2, respectively, and the results are as follows:
Example 1: Filtration of impurity particles in the electroless nickel plating waste liquid by a multi-stage security system is relatively complete, and in the subsequent electrodialysis treatment, the clogged area of the anion exchange membrane and the cation exchange membrane is small, and the exchange membrane is used. Has a long service life, can directly bury or process spray-cleaned impurity particles, and has low post-processing costs.
Example 2: Electrolytic nickel plating by one-stage filtration The filtration of impurity particles in the waste liquid is not complete, and the filtration tank is likely to be clogged. In the subsequent electrodialysis treatment, the anion exchange membrane and the cation exchange membrane are used. The clogged area is large, the service life of the exchange membrane is short, and the impurity particles obtained by filtration have non-electrodialytic nickel plating waste liquid attached to them, so they cannot be directly buried or processed, resulting in post-processing costs. high.
CONCLUSIONS: The multi-stage security filter system provided by Example 1 of the present invention can extend the useful life of the exchange membrane during electrodialysis treatment and reduce the treatment cost after filtering the impurity particles.
Experimental Example 2: Studying the effect of replacement of the electrode tank on the recycling of nickel and phosphorus resources The nickel and phosphorus resources in the electroless nickel plating waste liquid are recycled by the methods of Examples 1 and 3 to 6, and Comparative Group 1 The comparison group 1 is substantially the same as that of the first embodiment except for the following, and the first anode electrode tank, the first cathode electrode tank, and the second anode electrode tank in the comparison group 1 are used. The processing results are shown in Table 1 without swapping the positions of the second cathode electrode tank:
Table 1 Comparison table of the effect of replacing the electrode tank on the electroless nickel plating waste liquid treatment

Conclusion: By periodically replacing the cathode electrode tank and the anode electrode tank, the service life of the anion exchange membrane and the cation exchange membrane can be significantly extended and the processing cost can be reduced.
Experimental Example 3: Methods of Examples 1 and 7 to 10 for studying the influence of the number of returns of the post-treatment solution of the phosphorus concentrate and the post-treatment solution of the nickel concentrate on the method of recovering and reusing nickel and phosphorus resources. The nickel and phosphorus resources in the electroless nickel plating waste liquid are recycled and the comparison group 2 is set. The comparison group 2 is almost the same as the example 1 except for the following, and the phosphorus concentration in the comparison group 2 is obtained. The post-treatment liquid of the liquid and the post-treatment liquid of the nickel concentrate are directly discharged, and the treatment results are shown in Table 2.
Table 2 Comparison table of the effect of the return treatment of the post-treatment liquid on the electroless nickel plating waste liquid treatment

Conclusion: The more times the post-treatment liquid of phosphorus concentrate and the post-treatment liquid of nickel concentrate are returned, the lower the content of phosphorus and nickel in the effluent, but the higher the cost, and Table 2 As can be seen from the above, the method of Example 1 has high cost performance, the phosphorus and nickel contents in the effluent satisfy the discharge standard, and the treatment cost is relatively low.
Experimental Example 4: Electroless nickel plating waste liquid is treated by the methods of Examples 1 and 11 for studying the distinction between the stepwise separation and concentration of phosphorus and nickel in the waste liquid and the synchronous separation and concentration, and the results are as follows. :
In Example 1, phosphorus and nickel are separated and concentrated stepwise, and the anion unidirectional membrane electrodialysis system has a different electric field force strength from the cationic unidirectional membrane electrodialysis system, so that the treatment time is also different and the stage. The phosphorus and nickel in the electroless nickel plating waste liquid can be separated and concentrated to the maximum extent, but in Example 11, phosphorus and nickel are separated and concentrated synchronously, and in the anion unidirectional membrane electrodialysis system. , The strength of the electric field force is different from that of the cation unidirectional membrane electrodialysis system, and the processing time is also different. Alternatively, if the treatment time is long, the separation and concentration efficiency is lowered, so that the synchronous separation and concentration has high integration, but the separation and concentration efficiency is low, but the stepwise separation and concentration is two-step, but the separation efficiency is high.

Claims (7)

Step S1, the step of filtering the electroless nickel plating waste liquid by the waste liquid filtration multi-stage security filter system and removing the particle impurities in the electroless nickel plating waste liquid,
Step S2, Separation of Phosphorus in Waste Liquid Concentrated anion One-way membrane electrodialysis system (1) is used to perform electrodialysis treatment on the filtered non-electrolytic nickel-plated waste liquid, and the next step in the non-electrolytic nickel-plated waste liquid. Phosphorus and phosphite pass through the anion unidirectional membrane (11) under the action of electrodialysis and the phosphorus concentrate pool (14).
In the step of separating and concentrating phosphorus in the electroless nickel plating waste liquid to obtain a phosphorus concentrate,
Step S3, Separation of Nickel in Waste Liquid Using the concentrated cation unidirectional membrane electrodialysis system (2), electroless nickel plating waste liquid treated in step S2 is subjected to electrodialysis treatment to perform electroless nickel plating waste liquid. Under the action of electric field force, the nickel ions inside pass through the cation unidirectional film (21) and enter the nickel concentrate pool (24), and the nickel in the electroless nickel plating waste liquid is separated and concentrated to concentrate the nickel concentrate. And the steps to get
Step S4, Post-treatment of Phosphorus Concentrate The pH of the phosphorus concentrate obtained in Step S2 is adjusted to 2.5-4, the phosphorus concentrate is treated using electro-Fenton technology, and it is produced by the electro-Fenton reaction. OH
Under the action of, the hypophosphite and phosphite in the phosphorus concentrate are oxidized to orthophosphate, which reacts with the orthophosphate and Fe ³⁺ in the electrofenton reaction system to iron phosphate. A step of forming a crystal precipitate, processing the obtained iron phosphate crystal precipitate, recovering it into iron phosphate, and reusing it.
Step S5, Post-treatment of nickel concentrate The nickel concentrate obtained in step S3 is treated using a rotating electrolyzer, and the nickel ions in the nickel concentrate are reduced and deposited on the cathode to produce metallic nickel. Steps to collect and reuse,
A method for recovering and reusing nickel and phosphorus resources in an electroless nickel plating waste liquid, which comprises. In the filtration method of the multi-stage security filter system, the non-electrolytic nickel-plated waste liquid is introduced into the multi-stage security filter system, and the particles in the non-electrolytic nickel-plated waste liquid are gradually filtered and filtered by a plurality of sets of filtration tanks in the multi-stage security filter system. After blocking, the filtration opening diameter of the filtration tank gradually decreases from top to bottom, and after filtration, the surface of the particles obtained by filtration is cleaned and filtered using a spray cleaning device at the top of the filtration tank. Separate the non-electrolytic nickel plating waste liquid adhering to the particles and return it to the main body of the non-electrolytic nickel plating waste liquid.
The method for recovering and reusing nickel and phosphorus resources in the electroless nickel plating waste liquid according to claim 1. The anion unidirectional membrane electrodialysis system (1) is a first anion unidirectional membrane (11) for passing a non-electrolytic nickel plating waste liquid, and a first anion unidirectional membrane (11) provided on both sides of the anion unidirectional membrane (11). An anode electrode tank (12) and a first cathode electrode tank (13) are included, and a phosphorus concentrate pool (14) is provided between the first anode electrode tank (12) and the anion unidirectional film (11). After operating the anion unidirectional membrane electrodialysis system (1) for 5 to 7 days, the positions of the first anode electrode tank (12) and the first cathode electrode tank (13) are exchanged at the same time. The phosphorus concentrate is refilled in the phosphorus concentrate pool (14) between the first anode electrode tank (12) and the anion unidirectional membrane (11).
The method for recovering and reusing nickel and phosphorus resources in the electroless nickel plating waste liquid according to claim 1. The cation unidirectional membrane electrodialysis system (2) has a cation unidirectional membrane (21) through which a non-electrolytic nickel plating waste liquid is passed, and a second anode provided on both sides of the cation unidirectional membrane (21). A nickel concentrate pool (24) is provided between the second cathode electrode tank (23) and the cation unidirectional membrane (21), including an electrode tank (22) and a second cathode electrode tank (23). After operating the cation unidirectional membrane electrodialysis system (2) for 10 to 15 days, the positions of the second anode electrode tank (22) and the second cathode electrode tank (23) are exchanged, and at the same time, nickel is used. The concentrate is refilled in the nickel concentrate pool (24) between the second cathode electrode tank (23) and the cation unidirectional membrane (21).
The method for recovering and reusing nickel and phosphorus resources in the electroless nickel plating waste liquid according to claim 1. In the step of processing the iron phosphate crystal precipitate to obtain iron phosphate, the iron phosphate crystal precipitate is washed with distilled water 3 to 5 times, and the washed iron phosphate crystal precipitate is washed at 60 to 80 ° C. After drying for 30 to 50 minutes, the iron phosphate crystal precipitate is placed in a sintering furnace, and argon gas having a purity of 99.9% is used as a protective gas for the sintering furnace and baked at a heating rate of 5 ° C./min. After raising the temperature in the furnace to 130-150 ° C and holding it for 10-20 minutes, the temperature in the sintering furnace is raised to 350 at a heating rate of 10 ° C / min.
Includes heating to ~ 370 ° C. and heating under conditions of 350 to 370 ° C. for 20-30 minutes to obtain iron phosphate.
The method for recovering and reusing nickel and phosphorus resources in the electroless nickel plating waste liquid according to claim 1. The phosphorus concentrate treated by the electrofenton technique is returned to step S2 to continue separation and concentration, and phosphorus in the phosphorus concentrate is recovered, and the number of returns is 1 to 3 times.
The method for recovering and reusing nickel and phosphorus resources in the electroless nickel plating waste liquid according to claim 1. The nickel concentrate treated by the rotary electrolysis is returned to step S3 to continue separation and concentration, and nickel in the nickel concentrate is recovered, and the number of returns is 1 to 5 times.
The method for recovering and reusing nickel and phosphorus resources in the electroless nickel plating waste liquid according to claim 1.

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