JP5774290B2 - Treatment method of electroless nickel plating waste liquid - Google Patents

Description

  The present invention relates to a method for treating electroless nickel plating waste liquid, and more particularly, to a method for recycling and reusing electroless nickel plating waste liquid.

  An electroless nickel plating solution used for surface treatment of electronic parts and the like includes nickel sulfate as a nickel supply source and sodium hypophosphite as a reducing agent, and a complexing agent is added thereto. Sodium hypophosphite is oxidized during the plating process to become sodium phosphite. At the same time, nickel is deposited and consumed as a film. Therefore, nickel sulfate as a nickel supply source and hypophosphorous acid as a reducing agent are sometimes needed. Sodium plating and a pH adjuster are replenished to the plating solution.

  However, as the plating process is repeated, phosphite ions, sulfate ions, sodium ions, and metal ions eluted from the object to be plated accumulate in the plating solution. In particular, phosphite ions are by-products generated by oxidation of hypophosphite ions, so to speak, become waste products and concentrate in the liquid. For this reason, the quality of the plating film cannot be maintained by these secondary products, and the plating solution used to some extent becomes a waste solution.

  However, a large amount of nickel ions remain in this plating waste liquid at a high concentration. If this can be recovered and reused, it is possible to reduce the plating cost and the environmental load required for waste liquid treatment. Therefore, development of a method for reusing plating waste liquid is expected.

  Regarding a method for regenerating and reusing an electroless nickel plating waste liquid, for example, it is disclosed that an electroless nickel replenisher is prepared from the waste liquid using a nickel extract such as 2-hydroxy-5-nonylacetophenone oxime ( Patent Document 1). However, when this method is applied to an industrial scale continuous extraction device, a multistage extraction device, or the like, there is a problem that nickel cannot be efficiently recovered due to the slow extraction rate of nickel.

  In addition, an organic solvent containing a β-hydroxyoxime-based extractant and an acidic organic phosphorus compound is brought into contact with a nickel-containing aqueous solution, and nickel is extracted into the organic solvent, thereby efficiently extracting and recovering nickel from the nickel-containing aqueous solution. (Patent Document 2). However, this method has a problem in that the use and disposal of the organic solvent incurs a large cost and environmental load.

  In addition, a method is disclosed in which nickel ions are reacted with a chelate resin to form an adsorption precipitate, and later nickel is dissolved with an acid and recovered (Patent Document 3). However, in this method, a reaction coagulation water tank is used for the reaction, and a large water tank is necessary for the recovery of the precipitate. was there.

  Moreover, the method of making waste liquid alkaline by adding slaked lime etc., and also processing through microbial treatment is disclosed (patent document 4). However, this method has a problem that it takes 6 hours for microbial treatment and time and cost for filtration, and also requires treatment chemicals such as slaked lime which becomes waste that cannot be reused.

  Further, a method is disclosed in which a precipitation accelerator such as palladium is added to a plating waste solution to form a metallic nickel precipitate, which is filtered by a filter press and solidified (Patent Document 5). However, this method has a problem that the property of the deposited precipitate is good, but a large equipment cost and space are required for the solidification step of the precipitate such as a filter press.

  Moreover, the method of depositing nickel in a plating solution directly on the electrode surface by electrolysis with a copper electrode is disclosed (Patent Document 6). However, although this method is considered to have a large nickel recovery effect, there is a problem in that a large amount of power is required for nickel deposition, and the equipment becomes large and expensive.

  Further, a method is disclosed in which triazine thiol sodium is added to a plating solution, and magnetic separation and recovery are performed using the magnetic properties of the generated triazine thiol nickel (Patent Document 7). However, with this method, triazine thiol nickel is weak in magnetism, and it is necessary to apply a strong magnetic field, so the equipment becomes large, and post-treatment is necessary to reuse triazine thiol nickel. Therefore, there is a problem that the work becomes complicated.

  In addition, while providing a step of depositing nickel phosphite by adjusting the hydrogen ion concentration of the nickel-containing aqueous solution containing phosphorous acid, and a separation step of adsorbing the nickel phosphite deposited in this step to a magnetic field, A method in which the intensity of a magnetic field for adsorbing nickel phosphite is 3T or more is disclosed (Patent Document 8). However, this method has a problem in that it is expensive because nickel phosphite has weak magnetism and magnetic powder needs to be added in the separation step.

  Further, a method is disclosed in which nickel remaining in the aging solution of the electroless nickel plating solution is precipitated as nickel phosphite, and this nickel phosphite is reacted with sulfuric acid to be precipitated as nickel sulfate and recovered ( Patent Document 9). However, in this method, it takes too much time to crystallize nickel sulfate, the precipitated nickel sulfate crystals are fine and easy to redissolve, nickel sulfate is a strong acid, and filtration with a filter is difficult, phosphorous acid This method is difficult to carry out because there is a problem that it is difficult to recover high concentration nickel sulfate because it is likely to precipitate.

JP 2001-192846 A JP 2004-307983 A Japanese Patent Laid-Open No. 11-226596 JP-A-10-066998 JP-A-10-180266 JP-A-11-124679 JP 2009-120921 A JP 2009-120920 A Japanese Patent Laid-Open No. 10-183359

  Therefore, the present invention has a small amount of waste, a small environmental load, does not require a large-scale apparatus and space, and regenerates nickel sulfate and its containing from an electroless nickel plating waste liquid in a short time, at low cost and with a simple operation. It aims at providing the processing method of the electroless nickel plating waste liquid which can collect | recover and reuse a liquid.

  When the present inventors excite a high-temperature superconducting bulk body in its superconducting state to produce a magnet, it generates a strong magnetic field that is 20 times or more that of a conventional permanent magnet and approaches that of a large superconducting coil. It was found that this is possible (Japanese Patent No. 3598237). Furthermore, the present inventors have found that a paramagnetic substance having weak magnetism can be attracted using this “superconducting bulk magnet”, and have developed a magnetic separation apparatus to which this is applied (Japanese Patent Laid-Open No. 2003-2003). 334564). And even with alpha hematite (red rust component), which is considered to be weakly magnetized and not normally magnetically separated by a strong magnetic field, 90% or more can be separated from the dispersed water to a flow rate of 2 liters / minute. Got.

  On the other hand, as described above, there is already a technique for taking out nickel phosphite as a precipitate from the electroless nickel plating waste liquid and acid-treating it to crystallize it as nickel sulfate. In this prior art, nickel phosphite crystallized from the plating waste solution by pH adjustment is recovered, and this is redissolved with concentrated sulfuric acid and then cooled to precipitate nickel sulfate. However, the produced nickel sulfate lacks stability, such as being re-dissolved in the liquid during transfer and other treatments, and it takes a long time of several hours or more to modify all nickel phosphite to nickel sulfate. Therefore, it was practically impossible to construct a process capable of continuously processing this. In addition, since the crystallized nickel sulfate is produced in a fine and mixed form with nickel phosphite crystals, it has not been possible to separate it from solid nickel phosphite by conventional filtration filters. .

  In view of the above-described prior art, the present inventors have intensively studied a process for crystallizing nickel sulfate and a method for separating nickel sulfate from nickel phosphite by paying attention to the magnetic property of nickel sulfate. As a result, the present invention has been conceived.

That is, the processing method of electroless nickel plating waste water of the present invention, taken out as a precipitate phosphite nickel from an electroless nickel plating waste, crystallized as nickel sulfate the phosphite nickel is treated with sulfuric acid, phosphorous The nickel sulfate crystals are magnetically separated from nickel phosphite and recovered by utilizing the magnetic difference between nickel oxide and nickel sulfate .

  Further, the magnetic pole of the magnetic field generator is arranged close to the pipe water tank, and the magnetic field generated from the magnetic pole is applied to the aqueous solution or slurry containing the nickel sulfate crystal flowing in the pipe water tank to thereby form the nickel sulfate crystal. It is adsorbed in the vicinity of the magnetic pole.

  The magnetic field generator may be a permanent magnet, a superconducting bulk magnet, an electromagnet, or a superconducting solenoid magnet.

  The magnetic field generator is arranged on both sides of the pipe water tank.

  In addition, the magnetic field generator may be arranged so that both poles are magnetized to have different polarities or the same polarities and are opposed to each other.

  And moving the piping water tank in a direction parallel or perpendicular to the central axis of the magnetic pole to a range where the magnetic field generated from the magnetic pole does not reach to recover the nickel sulfate crystals adsorbed in the vicinity of the magnetic pole. Features.

  According to the treatment method of the electroless nickel plating waste liquid of the present invention, the electroless nickel plating can be performed in a short time, at a low cost and with a simple operation, with little waste, a small environmental load, and does not require a large apparatus and space. Nickel sulfate and a regenerated liquid containing the nickel sulfate can be recovered from the waste liquid and reused.

It is a flowchart which shows the processing method of the electroless nickel plating waste liquid of this invention. It is a schematic diagram which shows one Embodiment of the magnetic separation apparatus used for the processing method of the electroless nickel plating waste liquid of this invention. It is a schematic diagram which shows another embodiment of the magnetic separation apparatus used for the processing method of the electroless nickel plating waste liquid of this invention. It is a schematic diagram which shows another embodiment of the magnetic separation apparatus used for the processing method of the electroless nickel plating waste liquid of this invention. It is a schematic diagram which shows the effect | action of the magnetic separation apparatus using the permanent magnet used for the processing method of the electroless nickel plating waste liquid of this invention. It is a schematic diagram which shows the effect | action of the magnetic separation apparatus using the superconducting bulk magnet used for the processing method of the electroless nickel plating waste liquid of this invention. It is a schematic diagram which shows the effect | action of the magnetic separation apparatus using the normal electromagnet used for the processing method of the electroless nickel plating waste liquid of this invention. It is a schematic diagram which shows the effect | action of the magnetic separation apparatus using the superconducting electromagnet used for the processing method of the electroless nickel plating waste liquid of this invention. It is a schematic diagram which shows one Embodiment regarding collection | recovery of the adsorbent in the magnetic separation apparatus used for the processing method of the electroless nickel plating waste liquid of this invention. It is a schematic diagram which shows another embodiment regarding collection | recovery of the adsorbent in the magnetic separation apparatus used for the processing method of the electroless nickel plating waste liquid of this invention.

  The method of treating the electroless nickel plating waste liquid of the present invention takes out nickel phosphite as a precipitate from the electroless nickel plating waste liquid, treats the nickel phosphite with sulfuric acid, and crystallizes it as nickel sulfate. The crystals are recovered by magnetic separation. The present invention utilizes the fact that nickel sulfate crystals have magnetism, and a general strong magnetic field generator can be used for magnetic separation, for example, a superconducting bulk magnet, a superconducting solenoid magnet, or an ordinary magnet. An electromagnet (hereinafter referred to as an electromagnet) using a conductive coil and a permanent magnet can be used.

  In the process, the nickel sulfate particles that are crystallized by modifying the nickel phosphite produced from the plating waste liquid are present in the liquid simultaneously with the precipitation of the nickel phosphite. Therefore, when nickel sulfate having stronger magnetism is crystallized, it can be separated by utilizing the difference in magnetism from nickel phosphite. Therefore, even during the modification step from nickel phosphite to nickel sulfate, that is, during the modification reaction, the nickel sulfate particles can be adsorbed and separated by a magnetic field, and a high concentration of nickel sulfate can be recovered. This is the greatest feature of the present invention. For this reason, the processing time concerning collection | recovery is short, high concentration nickel collection | recovery is possible, a processing facility can be reduced in size, handling of a strongly acidic chemical | medical agent is few, and it is excellent also in safety. The present invention is extremely epoch-making in that it completely solves these process problems, which have been virtually impossible to recycle nickel, and completes a nickel plating solution circulation process.

  It is obvious that the magnetic field strength required in this magnetic separation process should be selected from the economically most advantageous method according to the required values of the processing amount, processing speed, etc. (these are referred to as processing scales for convenience). Will. When the scale of processing is small as in the test at the test tube level, it is economically effective even with a magnetic field of 1 Tesla or less of a permanent magnet, but in a small factory, a superconducting bulk magnet that is a compact and compact high magnetic field generator. However, when the processing time is short, an electromagnet using a normal conductive coil may be effective. In facilities with large treatment scales such as municipal wastewater treatment plants, the use of superconducting solenoid magnets may be sufficiently effective.

  The magnetically separated nickel sulfate and the aqueous solution or slurry containing the same can be returned to the electroless plating bath or electrolytic nickel plating bath for reuse. Therefore, it is possible to complete the recycling cycle of the electroless nickel plating waste liquid, which has not been practically possible until now. Part or much of the nickel phosphite stored in the reaction tank becomes nickel sulfate through this process and is returned to the plating tank through the filtrate recycling process. For this reason, the life of the plating solution can be extended.

  In addition, a superconducting bulk magnet, a small electromagnet, or a permanent magnet is used as a magnetic field generation source for the nickel recovery process, so that a large device and space are not required. Furthermore, since the production rate of nickel sulfate crystals is fast, it can be processed in a short time, and since there are few additives, there is little waste, the environmental load is small, the cost is low, and the simple operation of magnetic separation. Therefore, an extremely clean wastewater treatment becomes possible. However, when the amount of processing is large, a configuration using a large superconducting solenoid magnet may be economically effective. In addition, since it is possible to configure the superconducting solenoid magnet in a relatively small size, it is also included in the scope of the present invention to configure the superconducting solenoid magnet as a strong magnetic field generator.

  Hereinafter, specific description will be given with reference to the accompanying drawings.

  A large amount of nickel remains in the waste liquid generated by electroless nickel plating. First, this waste liquid is treated to form nickel phosphite, and further treated with sulfuric acid to crystallize nickel sulfate.

  This will be described with reference to FIG. The used waste liquid from the electroless nickel plating tank 11 is sent to the reaction tank 12. In the reaction vessel 12, the pH and temperature are adjusted, and nickel phosphite 13 is crystallized. The crystallized nickel phosphite 13 is sent to the filter press device 14 together with the solution, and is filtered and separated by the filter press device 14. Here, cake-like nickel phosphite 15 is obtained. The filtrate containing other solutes is sent to the filtrate reuse process and reused in the electroless nickel plating tank 11 after adjustment.

  The nickel phosphite 15 is sent to the sulfuric acid dissolution tank 16 and is dissolved in high-concentration sulfuric acid, so that the pH is adjusted to about 1 to 2 to become nickel sulfate 17 and a precipitate is generated. Nickel sulfate 17 is generated as fine crystals from a high-concentration sulfuric acid solution, and the size of the crystals varies depending on the stirring and flow of the solution. When placed in a beaker or other container and allowed to stand, the crystals of nickel sulfate 17 grow to the size of millimeters, but if flow such as agitation, convection, or transfer is applied, coarse crystal growth does not occur and is less than millimeters A fine crystal of crystallizes.

  Next, the crystallized nickel sulfate 17 is recovered by magnetic separation. Nickel phosphite has weak magnetism, but nickel sulfate 17 also has magnetism derived from nickel. However, since the magnetic strength as a substance is stronger than that of nickel phosphite 13, it is possible to magnetically separate these crystals more easily and efficiently using a strong magnetic field. Since the magnetic force generated in the magnetic particles by the magnetic field applied from the outside depends on the size of the particles, there is a difference in the phenomenon of adsorption of the crystallized nickel phosphite 13 on the magnetic poles. That is, coarse crystals are attracted by a weak magnetic field, and fine crystals are less likely to be attracted by a magnetic field.

  For this reason, even with the same processing performance, coarse crystals can be separated and recovered with a relatively weak magnetic field generator such as a permanent magnet, and as the crystals become finer, an electromagnet, superconducting bulk magnet, or super A conductive solenoid magnet is required. Since the fine nickel sulfate 17 crystals float on the liquid surface of the treatment tank and crystallize, the separation and adsorption separation of fine crystals immediately after crystallization in a strong magnetic field shortens the process and increases the processing efficiency. It is important from the viewpoint of improving the system and downsizing the apparatus.

  As the magnetic field generation source, a magnetic field generation source such as a superconducting bulk magnet, an electromagnet, or a permanent magnet is used. The maximum value of the spatial magnetic field that can be normally used is about 1 Tesla for permanent magnets, about 2 Tesla for electromagnets, and about 5 Tesla for superconducting bulk magnets. A superconducting solenoid magnet can also be used as a magnetic field generation source, and the size of the spatial magnetic field that can be used in this case is larger than that of the other magnetic field generation sources, and is about 3 to 10 Tesla at maximum. Since the effectiveness of each magnetic field generation source varies depending on the processing amount and processing time required for the separation step, the magnetic field generation source to be employed is selected according to the scale of processing.

  The precipitate of nickel sulfate 17 and the sludge slurry containing this at a high concentration are magnetically separated by a magnetic separation device 18 using a magnetic field generation source. Here, the fine crystals of nickel sulfate 17 are adsorbed in a strong magnetic field prior to nickel phosphite remaining unreacted or nickel phosphite crystallized from the liquid. Therefore, if a strong magnetic field is used, the fine nickel sulfate 17 crystal immediately after crystallization can be separated by the difference in its magnetic properties, and the nickel sulfate 17 can be recovered in a short time.

  The magnetically separated nickel sulfate 19 is reused.

  The separated nickel sulfate 19 is again put into the reaction vessel 12, and the presence of high-concentration nickel ions promotes crystallization of the nickel phosphite 13, and the nickel phosphite 13 is precipitated. The produced nickel phosphite is sent to the filtrate recycling process via the filter press 14. Note that the nickel sulfate 19 may be reused by being directly charged into the electroless nickel plating tank 11 without being charged into the reaction tank 12.

  In the conventional method of producing nickel sulfate by allowing sulfuric acid to act on the nickel phosphite precipitate, it takes a very long time to complete the reaction. In contrast, in the present invention, nickel sulfate precipitates are magnetically separated, so that nickel sulfate can be crystallized and simultaneously separated. Moreover, although nickel phosphite may crystallize depending on conditions, nickel sulfate can be separated before the crystallization. Therefore, high quality nickel sulfate can be recovered in a short time.

  Moreover, in the conventional method of separating by a filter, if the nickel sulfate crystallized is fine, filtration becomes difficult and a long time is required for filtration. In addition, the crystallized fine nickel sulfate crystals are easy to redissolve. On the other hand, in the present invention, fine nickel sulfate crystals can be efficiently separated, and the recovery efficiency is high.

  Hereinafter, an example of the magnetic separation device 18 that can be used in the treatment method of the electroless nickel plating waste liquid of the present invention will be described.

  In the example shown in FIG. 2, the magnetic pole 25 of the magnetic field generator 21 is arranged close to the pipe water tank 23, and the magnetic field 22 indicated by the arrow generated from the magnetic field generator 21 is emitted from the magnetic pole 25 and applied to the pipe water tank 23. It has come to be. Then, when an aqueous solution or slurry containing nickel sulfate precipitate is injected into the piping water tank 23 in the direction of the arrow 24, an aqueous solution or slurry containing nickel sulfate crystals flows inside the piping water tank 23, and the nickel sulfate 19 crystals are formed. It is attracted to and separated from the magnetic pole 25 of the magnetic field generator 21. The aqueous solution after the separation of the nickel sulfate 19 crystal is discharged in the direction of the arrow 24 '. The aqueous solution or slurry in which the nickel sulfate 19 crystals are separated and the concentration of nickel sulfate is reduced is charged again into the filtrate recycling process or the reaction vessel 12. Part or much of the nickel phosphite stored in the reaction tank becomes nickel sulfate through this process and is returned to the plating tank through the filtrate recycling process. For this reason, the life of the plating solution can be extended and reused.

  In this example, a permanent magnet, an electromagnet, a superconducting bulk magnet, a superconducting solenoid magnet, or the like can be used as the magnetic field generator 21 according to its scale, and is not limited to any of these.

  The example shown in FIG. 3 is the same as the example shown in FIG. 2 except that the pipe 26 is filled with a magnetic material 26. As the magnetic body 26, a stainless steel film or a small stainless sphere is used. The magnetic body 26 is magnetized by the magnetic field generator 21, and the nickel sulfate 19 is adsorbed by the magnetic field gradient generated by the magnetized magnetic body 26. To be separated.

  In this example, a permanent magnet, an electromagnet, a superconducting bulk magnet, a superconducting solenoid magnet, or the like can be used as the magnetic field generator 21 according to its scale, and is not limited to any of these.

  The example shown in FIG. 4 is the same as the example shown in FIG. 2 except that a pair of magnetic field generators 27 and 28 are arranged on both sides of the piping water tank 23 instead of the magnetic field generator 21. Also in this example, the magnetic body 26 may be filled in the piping water tank 23 as in the example shown in FIG. Since the magnetic field space generated by the pair of magnetic poles is wider than that of a single pole, the magnetic separation performance is improved. In general, an improvement in processing flow rate can be expected. Also in this case, a magnetic material may be disposed between the magnetic poles as shown in FIG. 3, and an increase in magnetic separation performance and throughput can be expected. Further, the same effect can be obtained even if the magnetic field space is configured by opposingly arranging magnetic poles magnetized to the same pole. In this case, the repulsive magnetic field lines are widely distributed in a cusp shape. In this example, a permanent magnet, an electromagnet, a superconducting bulk magnet, a superconducting solenoid magnet, or the like can be used as the magnetic field generator 21 according to its scale, and is not limited to any of these.

  FIG. 5 shows an application example of the permanent magnet in the present invention. A permanent magnet 30 is fixed by a support 31 and a base 32, and a magnetic field generated from the permanent magnet 30 is applied to the pipe water tank 23. When an aqueous solution or slurry containing nickel sulfate precipitates is poured into the piping water tank 23 in the direction of the arrow 24, nickel sulfate particles 17 indicated by white circles are attracted to the magnetic poles, and the nickel sulfate 19 precipitates are separated. The aqueous solution containing nickel phosphite 13 particles indicated by black circles after most of the precipitate of nickel sulfate 19 is separated is discharged in the direction of arrow 24 '. In this example, the flowing direction of the aqueous solution or slurry is the vertical direction, but may be either the vertical direction or the horizontal direction.

  As shown in FIG. 4, the magnetic poles can be opposed to each other. Such a magnetic pole arrangement enables the expansion of the strong magnetic field space, improves the performance of magnetic separation, and is effective in improving the efficiency of the entire process.

  Further, the configuration shown in FIG. 3 in which a stainless steel filter or a magnetic body 26 such as a stainless sphere is inserted into the piping water tank 23 is effective. The adsorption performance is improved by the magnetic field of the magnetic body 26, and the process efficiency is improved. .

  FIG. 6 shows an application example of the superconducting bulk magnet in the present invention. A superconducting bulk magnet 40 that generates a magnetic field of up to 3 Tesla is fixed inside a magnetic pole 41 serving as a vacuum vessel, and is cooled by a refrigerator 43 driven by a compressor 42 to be in a superconducting state. Already excited, it applies a strong magnetic field to the piping tank 23. Then, when an aqueous solution or slurry containing nickel sulfate precipitates is injected into the piping water tank 23 in the direction of the arrow 24, the nickel sulfate 19 precipitates are separated by being attracted to the magnetic poles as in FIG. The strong magnetic field and steep magnetic field gradient of the superconducting bulk magnet work effectively, resulting in an efficient configuration with excellent magnetic separation performance.

  As shown in FIG. 4, the magnetic poles can be opposed to each other. Such a magnetic pole arrangement enables the expansion of the strong magnetic field space, improves the performance of magnetic separation, and is effective in improving the efficiency of the entire process. Further, the same separation effect can be obtained even if the magnetic poles are magnetized to the same polarity and arranged opposite to each other. Further, the configuration shown in FIG. 3 in which a stainless steel filter or a magnetic body 26 such as a stainless sphere is inserted into the piping water tank 23 is effective. The adsorption performance is improved by the magnetic field of the magnetic body 26, and the process efficiency is improved. . Due to the weak magnetism of the nickel phosphite 13, the nickel phosphite 13 is adsorbed by mixing with the nickel sulfate 19 when the flow rate is slow, so the flow rate and the shape and structure of the piping tank 23 are adjusted for separation. .

  FIG. 7 shows an application example of the electromagnet in the present invention. A magnetic pole 50 of an electromagnet that generates a magnetic field of up to 2 Tesla is magnetized by a coil 51 around it, and a magnetic field is applied to the piping tank 23. In many cases of the electromagnet, the magnetic pole 52 and the coil 53 are arranged so as to face each other, and a magnetic circuit is formed on the back surface thereof by the iron yoke 54. When an aqueous solution or slurry containing nickel sulfate precipitates is injected into the pipe water tank 23, the nickel sulfate 19 precipitates are separated by being sucked by the magnetic pole 50 and the magnetic pole 52.

  Further, the configuration shown in FIG. 3 in which a stainless steel filter or a magnetic body 26 such as a stainless sphere is inserted into the piping water tank 23 is effective. The adsorption performance is improved by the magnetic field of the magnetic body 26, and the process efficiency is improved. .

  FIG. 8 shows an application example of the superconducting solenoid magnet in the present invention. A superconducting solenoid magnet 60 that generates a magnetic field of up to 10 Tesla is constituted by a superconducting coil 61 in the vacuum vessel. The superconducting coil 61 is cooled by the refrigerator 62 and is in a superconducting state. The excited spatial magnetic field is applied to the piping water tank 23, and when an aqueous solution or slurry containing nickel sulfate precipitates flows in the pipe water tank 23, the nickel sulfate 19 precipitates are magnetically separated. Because of the configuration characterized by a strong magnetic field in space, it is effective to apply to facilities with a large processing scale.

  As shown in FIG. 4, the magnetic poles can be opposed to each other. Such a magnetic pole arrangement enables the expansion of the strong magnetic field space, improves the performance of magnetic separation, and is effective in improving the efficiency of the entire process.

  Further, the configuration shown in FIG. 3 in which a stainless steel filter or a magnetic body 26 such as a stainless sphere is inserted into the piping water tank 23 is effective. The adsorption performance is improved by the magnetic field of the magnetic body 26, and the process efficiency is improved. .

  FIG. 9 shows an example of a configuration related to recovery of precipitation of magnetically separated nickel sulfate 19 that is characteristic of the present invention, using a superconducting bulk magnet as an example of a magnetic field generator. By moving the piping water tank 23 in the magnetic field space generated from the magnetic pole of the magnetic field generator 70 to a range where the magnetic field does not reach, that is, in a direction perpendicular to the central axis of the magnetic field of the magnetic field generator 70 The effect of magnetic field adsorption can be easily eliminated, and the crystal of nickel sulfate 19 adsorbed in the vicinity of the magnetic pole of the magnetic field generator 70 can be easily removed from the piping tank 23 using compressed air, water, organic solvent, etc. Can be discharged. In particular, the magnetic field space using a superconducting bulk magnet is characterized by a strong magnetic field with a high degree of freedom, and is excellent in magnetic separation performance and handling at the time of recovery.

  FIG. 10 shows another example of the configuration relating to the recovery of the precipitate of magnetically separated nickel sulfate 19 characteristic of the present invention, using a superconducting bulk magnet as an example of a magnetic field generator. By moving the piping tank 23 in the magnetic field generated by the magnetic field generator 70 to a range that does not reach the magnetic field in the direction parallel to the central axis of the magnetic field generation, that is, the central axis of the magnetic pole of the magnetic field generator 70 The effect of magnetic field adsorption can be eliminated, and the crystal of nickel sulfate 19 adsorbed in the vicinity of the magnetic pole of the magnetic field generator 70 can be easily discharged from the piping tank 23 to the outside using compressed air, water, organic solvent, etc. can do. In particular, the magnetic field space using a superconducting bulk magnet is characterized by a strong magnetic field with a high degree of freedom, and is excellent in magnetic separation performance and handling at the time of recovery.

  In addition, as a configuration of the magnetic separation device, for example, as disclosed in Japanese Patent Application Laid-Open No. 2009-120920, a pipe water tank is arranged on the upper part of the magnetic field generator so that the magnetic field is radiated in the vertical direction. It may be. Further, as disclosed in Japanese Patent Application Laid-Open No. 2009-119421, the adsorption separated from the pipe water tank by alternately changing the pair of water tank pipes inside and outside the magnetic field space and pushing the adsorbate with compressed air or the like. You may comprise so that an object may be taken out. Further, as disclosed in Japanese Patent No. 4129548, the adsorbate may be separated from the piping water tank by continuously rotating the disk.

21, 27, 28 Magnetic field generator
25, 41, 50, 52 magnetic pole
23 Piping tank
30 Permanent magnet
40 Superconducting bulk magnet
60 Superconducting solenoid magnet

Claims (6)

Nickel phosphite is removed from the electroless nickel plating waste solution as a precipitate, this nickel phosphite is treated with sulfuric acid to crystallize as nickel sulfate, and the difference in magnetism between nickel phosphite and nickel sulfate is utilized to make this sulfate. processing method of electroless nickel plating effluent and recovering magnetically separating the crystals of nickel from phosphorous acid nickel. The magnetic pole of the magnetic field generator is arranged close to the pipe water tank, and the magnetic field generated from the magnetic pole is applied to the aqueous solution or slurry containing the nickel sulfate crystal flowing inside the pipe water tank so that the nickel sulfate crystal is The method for treating an electroless nickel plating waste liquid according to claim 1, wherein the electroless nickel plating waste liquid is adsorbed in the vicinity of. The electroless nickel plating waste liquid treatment method according to claim 2, wherein any one of a permanent magnet, a superconducting bulk magnet, an electromagnet, and a superconducting solenoid magnet is used as the magnetic field generator. The method for treating an electroless nickel plating waste liquid according to claim 2 or 3, wherein the magnetic field generator is disposed on both sides of the piping water tank. 5. The method for treating an electroless nickel plating waste liquid according to claim 4, wherein both poles of the magnetic field generator are magnetized to have different polarities or the same polarities and are opposed to each other. Moving the piping water tank in a direction parallel to or perpendicular to the central axis of the magnetic pole to a range where the magnetic field generated from the magnetic pole does not reach, and collecting nickel sulfate crystals adsorbed in the vicinity of the magnetic pole, The processing method of the electroless nickel plating waste liquid of any one of Claims 2-5 to do.

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