A method for recycling waste metal powder based on 3D printing electrochemistry

Abstract

The present application belongs to the field of additive manufacturing, and particularly relates to a method for recycling and regenerating 3D printing waste metal powder based on electrochemistry. The method comprises the following steps: 1) screening the recycled waste powder to remove large-particle impurities; 2) preparing an electrochemical treatment solution, wherein the main components include 1-30 wt% ion conductive resin, 1-10 wt% chelating agent, 1-15 wt% acid, 1-15 wt% supporting electrolyte, and the balance of deionized water; 3) circulating the treatment solution into the cavity of an electrochemical treatment device, performing electrochemical oxidation first, then performing electrochemical reduction by reversing the positive and negative electrodes, and controlling the electrical parameters to perform electrochemical treatment; and 4) filtering and vacuum drying the treated powder to obtain regenerated powder. The present application is simple and efficient, low in cost, safe and environmentally friendly, has a waste powder recycling rate of >75%, a regenerated metal powder oxygen content of <0.1%, and a sphericity of >95%, and can meet the use requirements of 3D printing forming and reduce the cost of metal 3D printing.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of additive manufacturing, in particular to a method for recycling and regenerating 3D printing waste metal powder based on electrochemistry. BACKGROUND

[0002] At present, with the progress of science and technology and demand leading, the additive manufacturing technology (also known as 3D printing technology) has developed rapidly, especially the 3D printing products of metal, which have realized popular application in many fields. However, a large amount of metal powder needs to be consumed in the process of 3D printing, and the metal powder collected in the process is often discarded due to defects such as low sphericity (<85%) and high oxygen content (>0.2wt%) or other structural problems, and cannot be used. At present, more and more 3D printing waste metal powder is discarded, which not only causes waste of resources, but also causes great environmental pollution and fire safety problems. In view of the fact that the price of raw material powder for 3D printing metal is relatively high, and there is no effective method for recycling and regenerating the metal powder after 3D printing at present, it has become an urgent demand in this field to develop an effective 3D printing metal powder recycling and regenerating technology to realize the recycling and utilization of 3D printing waste powder, which not only can create great economic benefits, but also meets the double carbon target of low carbon emission reduction, and can bring significant social benefits. SUMMARY

[0003] In view of the problem that the recycled 3D printing metal powder cannot be regenerated and utilized, the purpose of the present application is to provide a method for recycling and regenerating 3D printing waste metal powder based on electrochemistry, to realize the regeneration of 3D printing metal powder, to make it be used for 3D printing production again, to improve the utilization rate of metal powder, and to reduce the cost.

[0004] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0005] A method for recycling and regenerating 3D printing waste metal powder based on electrochemistry, comprising the following steps:

[0006] (1) screening the recycled waste powder to remove large particle impurities;

[0007] (2) preparing an electrochemical treatment solution, the main components of which include: ion conductive resin 1-30wt%, chelating agent 1-10wt%, acid 1-15wt%, supporting electrolyte 1-15wt%, and deionized water in balance;

[0008] (3) circulating the electrochemical treatment solution into the cavity of the electrochemical treatment device, first performing electrochemical oxidation, then performing electrochemical reduction by reversing the positive and negative electrodes, and controlling the electrical parameters to perform electrochemical treatment;

[0009] (4) filtering and vacuum drying the treated powder to obtain regenerated powder.

[0010] The method for recycling and regenerating waste metal powder based on electrochemistry 3D printing, the waste metal powder for regenerating treatment is nickel-based superalloy, cobalt-based superalloy, titanium alloy, aluminum alloy, stainless steel, iron powder, copper alloy or tungsten alloy.

[0011] The method for recycling and regenerating waste metal powder based on electrochemistry 3D printing, the nickel-based superalloy is GH3536, GH4169 or GH4151, the cobalt-based superalloy is GH5188, GH159, GH605, K640 or DZ40M, the titanium alloy is TA8, TA9, TA10, TA17, TA18, TB5, TB8, TB9, TC4, TC1, TC2, TC3 or TC10, and the stainless steel is 304 or 316L.

[0012] The method for recycling and regenerating waste metal powder based on electrochemistry 3D printing, in step (1), the mesh number of the screen for removing large particle impurities is 100-300 mesh.

[0013] The method for recycling and regenerating waste metal powder based on electrochemistry 3D printing, in the electrochemical treatment solution:

[0014] The ion conductive resin is one or a mixture of two or more of polyvinylidene fluoride resin, polysulfone, polyether ether ketone, polybenzothiazole, sulfonated polyethylene, sulfonated polypropylene, polyether sulfone, polyimide, perfluorosulfonic acid resin, perfluorocarboxylic acid resin, polybenzimidazole, and the shape of the ion conductive resin is granular, including spherical, flaky or irregularly shaped resin particles, and the particle size of the granular ion conductive resin is 1-1000 μm.

[0015] The chelating agent is one or a mixture of two or more of ethylenediamine, 2,2'-dipyridyl, 1,10-phenanthroline, oxalate, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, hydroxyethylethylenediaminetriacetic acid, aminotriacetic acid, hydroxyethylenediphosphonic acid, aminotri(methylene)phosphonic acid, ethylenediaminetetra(methylene)phosphonic acid, diethylenetriaminepenta(methylene)phosphonic acid, triethylenetetraaminehexa(methylene)phosphonic acid, and polyamino polyether tetra(methylene)phosphonic acid.

[0016] The acid is one or a mixture of two or more of hydrochloric acid, nitric acid, acetic acid, perchloric acid, methylsulfonic acid, aminosulfonic acid, sulfuric acid, formic acid, boric acid, phosphoric acid, orthosilicic acid and metaaluminic acid.

[0017] The supporting electrolyte is one or a mixture of two or more of soluble chlorides, sulfates, nitrates, carbonates, phosphates, acetates, perchlorates, orthosilicates and metaaluminates of sodium, potassium, lithium, magnesium, aluminum, calcium, zinc, iron, tin, barium, strontium, rubidium and cesium.

[0018] The electrochemical-based 3D printing waste metal powder recycling method, the electrochemical treatment device is composed of a cavity, a positive electrode, a negative electrode and a diaphragm, the positive and negative electrodes share the same electrochemical treatment liquid, and the diaphragm is coated on the negative electrode.

[0019] The positive electrode is a dimensionally stable electrode, specifically one of a boron-doped diamond thin film electrode, a titanium-based ruthenium-iridium electrode, a titanium-based iridium-tantalum electrode, a titanium-based ruthenium-indium-tin electrode, a titanium-based tin-antimony oxide electrode, a titanium-based sub-titanium oxide electrode and a titanium-based lead dioxide electrode.

[0020] The negative electrode material includes at least one of a metal material and a carbon material, wherein the metal material includes at least one of stainless steel, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, niobium, tantalum, zirconium, tungsten, cerium, aluminum, bismuth, rhenium, barium, osmium, tin, lead, gold, silver, platinum, palladium, iridium, rhodium, molybdenum and ruthenium, and the carbon material includes any one of graphite felt, carbon felt, graphite, glassy carbon, boron-doped diamond, activated carbon, graphene, carbon fiber, carbon nanotube and carbon sponge.

[0021] The electrode shape includes any one of a sheet shape, a rod shape, a wire shape, a particle shape, a sponge shape, a mesh shape and a porous structure, the constant temperature of the positive and negative electrode electrochemical treatment liquid is 10-90 DEG C, the inter-electrode distance of the positive and negative electrodes is 1-100 mm, and the area ratio of the positive and negative electrodes is 1:10-10:1.

[0022] The diaphragm is at least one of an ion exchange membrane and a porous membrane, the ion exchange membrane is one of a diaphragm made of polybenzothiazole, polybenzimidazole, sulfonated polyethylene, polyether sulfone, sulfonated polypropylene, polyimide, polysulfone, perfluorosulfonic acid resin, polyether ether ketone, perfluorocarboxylic acid resin and polyvinylidene fluoride, and the porous membrane is a porous fiber membrane, a non-woven fabric membrane or a fiber paper made of polyethylene, polypropylene, polyvinyl chloride, nylon, polyester, polyvinylidene fluoride, polytetrafluoroethylene and glass fiber.

[0023] The electrochemical-based 3D printing waste metal powder recycling method, the electrochemical treatment process uses a two-step process of electrochemical oxidation + electrochemical reduction, wherein the electrochemical oxidation process is any one of constant-current electrochemical oxidation, constant-voltage electrochemical oxidation and constant-current pulse electrochemical oxidation, and the electrochemical oxidation time is 60-600 min; the electrochemical reduction process is any one of constant-current electrochemical reduction, constant-voltage electrochemical reduction and constant-current pulse electrochemical reduction, and the electrochemical reduction time is 0-30 min.

[0024] In the constant-voltage electrochemical oxidation, the voltage is 1-100 V; in the constant-current electrochemical oxidation, the current density calculated according to the working area of the negative electrode is 10-500 mA / cm 2 ; and in the constant-current pulse electrochemical oxidation, the current density calculated according to the working area of the negative electrode is 10-1000 mA / cm2 , the frequency is 200-2000Hz, and the duty cycle is 20%-80%;

[0025] In the constant-voltage electrochemical reduction, the voltage is 1-100V; in the constant-current electrochemical reduction, the current density calculated according to the working area of the negative electrode is 1-50mA / cm 2 ; in the constant-current pulse electrochemical reduction, the current density calculated according to the working area of the negative electrode is 1-100mA / cm 2 ; the frequency is 200-2000Hz, and the duty cycle is 20%-80%.

[0026] The electrochemical treatment liquid of the 3D printing waste metal powder recycling and regenerating method based on electrochemistry is circulated by a circulating pump to flow through the surface of the metal powder in the cavity, and the flow rate is 0-30m 3 / h.

[0027] The metal powder after electrochemical treatment is subjected to vacuum drying treatment, the drying temperature is 50-400 DEG C, and the time is 0.5-10h.

[0028] The design idea of the present application is:

[0029] The polarization effect in an acid system by means of electrochemical technology is utilized, the friction and collision between the circulating resin particles and the surface of the metal powder are caused, the dissolution of the irregular edges and corners on the surface of the metal powder is accelerated, the stable dissolution of the metal ions in the solution is realized by means of the coordination effect of the chelating agent, and the surface oxide film of the metal powder is quickly dissolved by means of the instantaneous electrochemical reduction, so that the oxygen content on the surface of the metal powder is reduced. The present application has the advantages of simple process, high efficiency, low cost, safety, environmental protection, waste powder recycling rate >75%, oxygen content <0.1wt% in the regenerated metal powder, and spherical degree >95%, and can meet the use requirements of 3D printing forming and reduce the cost of metal 3D printing.

[0030] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0031] 1. The process of the present application is simple, easy to operate, and has obvious environmental protection characteristics.

[0032] 2. The present application has low investment cost, high recycling rate (>75%), and is suitable for industrial large-scale production.

[0033] 3. The regenerated metal powder of the present application has high spherical degree, low oxygen content and good stability.

[0034] 4. The present application has an important leading role in the recycling of metal resources, the upgrading of low-emission environmental protection process and the cost reduction of 3D printing products in the field of metal resources in China. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 The figure shows the principle of the method for recycling waste metal powder of 3D printing based on electrochemistry. Wherein, 1-anode; 2-electrochemical treatment solution; 3-metal powder; 4-cathode; 5-separator; 6-power supply; 7-circulating pump. DETAILED DESCRIPTION

[0036] In the specific implementation process, the process of the method for recycling waste metal powder of 3D printing based on electrochemistry is as follows: 1) the recycled waste powder is sieved to remove large particle impurities and then placed in the cavity of the electrochemical treatment device; 2) the electrochemical treatment solution is prepared, and the main components include: ion conductive resin 1-30wt% (preferably 2-25wt%), chelating agent 1-10wt% (preferably 2-8wt%), acid 1-15wt% (preferably 2-12wt%), supporting electrolyte 1-15wt% (preferably 2-13wt%), and deionized water in the remainder; 3) the electrochemical treatment solution is pumped into the cavity of the electrochemical treatment device by a circulating pump, and then electrochemical oxidation is performed, followed by electrochemical reduction by reversing the anode and cathode (anode 1 is used as a cathode, and cathode 4 is used as an anode), and the electrochemical treatment is performed by controlling the electrical parameters; 4) the treated powder is filtered and vacuum dried to obtain regenerated powder.

[0037] As shown in Figure 1 The method for recycling waste metal powder of 3D printing based on electrochemistry uses an electrochemical treatment device including an anode 1, an electrochemical treatment solution 2, metal powder 3, a cathode 4, a separator 5, a power supply 6, and a circulating pump 7, and the specific structure is as follows: the lower end of the cathode 4 coated with the separator 5 extends into the electrochemical treatment solution 2, the upper ends of the anode 1 and the cathode 4 are respectively connected to the positive and negative poles of the power supply 6 through wires, the inlet of the circulating pump 7 is connected to the lower part of the electrochemical treatment solution 2 through a pipeline, the outlet of the circulating pump 7 is connected to the upper part of the electrochemical treatment solution 2 through a pipeline, and the waste metal powder 3 in the electrochemical treatment solution 2 is recycled and regenerated during the electrochemical treatment process.

[0038] In order to further understand the present application, the following examples are used to describe the present application, but the examples are only used to further illustrate the features and advantages of the present application, and are not used to limit the claims of the present application.

[0039] Example 1

[0040] An electrochemical treatment solution was prepared by uniformly mixing 6 wt% of a granular (size 200 μm) polybenzimidazole resin, 5 wt% of ethylenediamine, 2 wt% of H2SO4, 10 wt% of sodium sulfate, and the balance of deionized water. The nickel-based superalloy powder G3536 was placed in the cavity of an electrochemical treatment device after removing large-particle impurities through a 100-mesh screen. The anode was a boron-doped diamond thin film electrode, the cathode was a stainless steel plate, the separator was a polybenzimidazole resin separator coated on the cathode, the distance between the anode and the cathode was 1 mm, and the area ratio of the anode to the cathode was 1:10. The electrochemical treatment solution had a flow rate of 5 m 3 / h, and constant-current electrooxidation was performed at a current density of 100 mA / cm 2 , a constant temperature of 30°C, and an electrooxidation time of 300 min. Then, the positive and negative electrodes were reversed, and electroreduction was performed using constant-current electroreduction at a current density of 10 mA / cm 2 , a constant temperature of 30°C, and an electroreduction time of 50 min. The treated metal powder was then filtered and dried at 150°C for 2 h to obtain a regenerated metal powder. The specific indexes are shown in Table 1.

[0041] Example 2

[0042] An electrochemical treatment solution was prepared by uniformly mixing 3.5 wt% of aminotrimethylenephosphonic acid, 4 wt% of HNO3, 20 wt% of a granular (size 300 μm) sulfonated polyether ether ketone resin, 14 wt% of sodium sulfate, and the balance of deionized water. The cobalt-based superalloy powder GH5188 was placed in the cavity of an electrochemical treatment device after removing large-particle impurities through a 150-mesh screen. The anode was a titanium-based ruthenium-iridium electrode, the cathode was a graphite felt, the separator was a polybenzothiazole resin separator coated on the cathode, the distance between the anode and the cathode was 20 mm, and the area ratio of the anode to the cathode was 1:8. The electrochemical treatment solution had a flow rate of 15 m 3 / h, and constant-current electrooxidation was performed at a current density of 200 mA / cm 2 , a constant temperature of 40°C, and an electrooxidation time of 100 min. Then, the positive and negative electrodes were reversed, and electroreduction was performed using constant-voltage electroreduction at a voltage of 10 V, a constant temperature of 40°C, and an electroreduction time of 5 min. The treated metal powder was then filtered and dried at 250°C for 3 h to obtain a regenerated metal powder. The specific indexes are shown in Table 1.

[0043] Example 3

[0044] An electrochemical treatment solution was prepared by uniformly mixing 2,2'-dipyridyl 4 wt%, H3PO4 4.5 wt%, granular (size 800 μm) perfluorosulfonic acid resin 15 wt%, sodium nitrate 7 wt%, and deionized water in a remainder amount. Titanium alloy powder TC4, after removing large particle impurities through a 140-mesh screen, was placed in the cavity of an electrochemical treatment device; the positive electrode was a titanium-based iridium-tantalum electrode, the negative electrode was carbon felt, the separator was a polyimide resin separator coated on the negative electrode, the positive and negative electrode spacing was 30 mm, and the positive and negative electrode area ratio was 1:6; the electrochemical treatment solution flow rate was 25 m 3 / h, constant voltage electro-oxidation was used, the voltage was 20 V, the constant temperature was 50 °C, and the electro-oxidation time was 400 min. Then, by reversing the positive and negative electrodes, electro-reduction was performed, constant current pulse electro-reduction was used, the current density was 800 mA / cm 2 , the frequency was 1200 Hz, the duty cycle was 60%, the constant temperature was 50 °C, and the electro-reduction time was 3 min. The treated metal powder was then filtered and dried at 350 °C for 4 h to obtain a regenerated metal powder, and the specific indicators are shown in Table 1.

[0045] Example 4

[0046] An electrochemical treatment solution was prepared by uniformly mixing hydroxyethyl ethylenediamine triacetic acid 2.5 wt%, HNO3 2.5 wt%, spherical (size 600 μm) sulfonated polyethylene resin 12 wt%, potassium chloride 8 wt%, and deionized water in a remainder amount. Titanium alloy powder TCA8, after removing large particle impurities through a 230-mesh screen, was placed in the cavity of an electrochemical treatment device; the positive electrode was a titanium-based lead dioxide electrode, the negative electrode was glassy carbon, the separator was a polyether ether ketone resin separator coated on the negative electrode, the positive and negative electrode spacing was 50 mm, and the positive and negative electrode area ratio was 1:9; the electrochemical treatment solution flow rate was 8 m 3 / h, constant current pulse electro-oxidation was used, the current density was 500 mA / cm 2 , the frequency was 1500 Hz, the duty cycle was 50%, the constant temperature was 60 °C, and the electro-oxidation time was 500 min. Then, by reversing the positive and negative electrodes, electro-reduction was performed, constant current pulse electro-reduction was used, the current density was 800 mA / cm 2 , the frequency was 1000 Hz, the duty cycle was 80%, the constant temperature was 60 °C, and the electro-reduction time was 16 min. The treated metal powder was then filtered and dried at 450 °C for 1 h to obtain a regenerated metal powder, and the specific indicators are shown in Table 1.

[0047] Example 5

[0048] An electrochemical treatment solution was prepared by uniformly mixing 1 wt% of ethylenediaminetetraacetic acid, 2.2 wt% of methyl sulfonic acid, 26 wt% of spherical (size 600 μm) sulfonated polyethylene resin, 9 wt% of potassium sulfate, and the balance of deionized water. The titanium alloy powder TCA8, after removing large-particle impurities through a 230-mesh screen, was placed in the cavity of an electrochemical treatment device; the positive electrode was a titanium-based ruthenium-iridium electrode, the negative electrode was graphite, a sulfonated polystyrene resin separator was coated on the negative electrode, the distance between the positive and negative electrodes was 60 mm, and the area ratio of the positive to negative electrodes was 10:1; the flow rate of the electrochemical treatment solution was 18 m 3 / h, constant-current electrooxidation was used, the current density was 500 mA / cm 2 , the constant temperature was 70°C, and the electrooxidation time was 400 min. Then, the positive and negative electrodes were reversed, and electroreduction was performed, constant-voltage electroreduction was used, the voltage was 20 V, the constant temperature was 70°C, and the electroreduction time was 9 min. The treated metal powder was then filtered and dried at 400°C for 4 h to obtain a regenerated metal powder, and the specific indexes are shown in Table 1.

[0049] Example 6

[0050] An electrochemical treatment solution was prepared by uniformly mixing 3 wt% of triethylenetetramine hexamethylenephosphonic acid, 3 wt% of sulfamic acid, 16 wt% of granular (size 800 μm) polyimide resin, 9 wt% of potassium nitrate, and the balance of deionized water. The stainless steel powder 316L, after removing large-particle impurities through a 260-mesh screen, was placed in the cavity of an electrochemical treatment device; the positive electrode was a titanium-based lead dioxide electrode, the negative electrode was a zinc electrode, a perfluorocarboxylic acid resin separator was coated on the negative electrode, the distance between the positive and negative electrodes was 70 mm, and the area ratio of the positive to negative electrodes was 8:1; the flow rate of the electrochemical treatment solution was 28 m 3 / h, constant-voltage electrooxidation was used, the voltage was 40 V, the constant temperature was 80°C, and the electrooxidation time was 600 min. Then, the positive and negative electrodes were reversed, and electroreduction was performed, constant-current electroreduction was used, the current density was 20 mA / cm 2 , the constant temperature was 80°C, and the electroreduction time was 4 min. The treated metal powder was then filtered and dried at 350°C for 1 h to obtain a regenerated metal powder, and the specific indexes are shown in Table 1.

[0051] Example 7

[0052] According to 2wt% triethylenediamine triacetic acid, 4wt% acetic acid, 30wt% granular (size 800μm) polysulfone resin, 9wt% magnesium chloride and deionized water balance, the electrochemical treatment solution is prepared by uniform mixing. The stainless steel powder 316L is put into the cavity of the electrochemical treatment device after removing large particle impurities through a 260 mesh screen; wherein the positive electrode is a boron-doped diamond film electrode, the negative electrode is a stainless steel plate, the separator is a polybenzimidazole resin separator, coated on the negative electrode, the positive and negative electrode spacing is 80mm, the positive and negative electrode area ratio is 9:1; the electrochemical treatment solution flow is 9m 3 / h, constant voltage electro-oxidation is adopted, the voltage is 80V, the constant temperature is 85℃, and the electro-oxidation time is 700min. Then the positive and negative electrodes are reversed, and electro-reduction is carried out, constant current electro-reduction is adopted, the current density is 10mA / cm 2 , the constant temperature is 85℃, and the electro-reduction time is 5min. Then the treated metal powder is filtered and dried at 210℃ for 4h to obtain the regenerated metal powder, and the specific indexes are shown in Table 1.

[0053] Table 1 Performance results of regenerated metal powder of examples

[0054]

[0055]

[0056] The results of the examples show that the method is simple, easy to operate, has high metal powder recovery rate, has obvious environmental protection characteristics, and is suitable for industrial large-scale production.

Claims

1. A method for recycling and regenerating waste metal powder from 3D printing based on electrochemistry, characterized in that, Includes the following steps: (1) Screen the recovered waste powder to remove large particles of impurities; (2) Prepare an electrochemical treatment solution, the main components of which include: 1-30 wt% ion-conducting resin, 1-10 wt% chelating agent, 1-15 wt% acid, 1-15 wt% supporting electrolyte, and the remainder deionized water. (3) The electrochemical treatment liquid is pumped into the cavity of the electrochemical treatment device for electrochemical oxidation first, and then the positive and negative electrodes are reversed for electro-reduction. The electrical parameters are controlled to carry out electrochemical treatment. (4) Filter the processed powder and vacuum dry it to obtain regenerated powder.

2. The method for recycling and regenerating waste metal powder from 3D printing based on electrochemistry as described in claim 1, characterized in that, The recycled waste metal powder is nickel-based superalloy, cobalt-based superalloy, titanium alloy, aluminum alloy, stainless steel, iron powder, copper alloy or tungsten alloy.

3. The method for recycling and regenerating waste metal powder from 3D printing based on electrochemistry as described in claim 2, characterized in that, Nickel-based superalloys are GH3536, GH4169, or GH4151; cobalt-based superalloys are GH5188, GH159, GH605, K640, or DZ40M; titanium alloys are TA8, TA9, TA10, TA17, TA18, TB5, TB8, TB9, TC4, TC1, TC2, TC3, or TC10; and stainless steel is 304 or 316L.

4. The method for recycling and regenerating waste metal powder from 3D printing based on electrochemistry as described in claim 1, characterized in that, In step (1), the mesh size of the sieve used to remove large particulate impurities is 100 to 300 mesh.

5. The method for recycling and regenerating waste metal powder from 3D printing based on electrochemistry as described in claim 3, characterized in that, In the electrochemical treatment solution: The ion-conducting resin is one or a mixture of two or more of the following: polyvinylidene fluoride resin, polysulfone, polyether ether ketone, polybenzothiazole, sulfonated polyethylene, sulfonated polypropylene, polyethersulfone, polyimide, perfluorosulfonic acid resin, perfluorocarboxylic acid resin, and polybenzimidazole. The ion-conducting resin is in the form of granules, including spherical, flake, or irregularly shaped resin particles. The particle size of the granular ion-conducting resin is between 1 μm and 1000 μm. The chelating agent is one or a mixture of two or more of the following: ethylenediamine, 2,2'-bipyridine, 1,10-phenanthroline, oxalate, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, hydroxyethylethylenediaminetriacetic acid, aminotriacetic acid, hydroxyethylidene diphosphonic acid, aminotrimethylenephosphonic acid, ethylenediaminetetramethylenephosphonic acid, diethylenetriaminepentamethylenephosphonic acid, triethylenetetraaminehexamethylenephosphonic acid, and polyaminopolyether tetramethylenephosphonic acid; The acid is one or a mixture of two or more of the following: hydrochloric acid, nitric acid, acetic acid, perchloric acid, methanesulfonic acid, aminosulfonic acid, sulfuric acid, formic acid, boric acid, phosphoric acid, orthosilicic acid, and aluminic acid. Supported electrolytes are one or more of the following: sodium, potassium, lithium, magnesium, aluminum, calcium, zinc, iron, tin, barium, strontium, rubidium, cesium soluble chlorides, sulfates, nitrates, carbonates, phosphates, acetates, perchlorates, orthosilicates, and aluminates.

6. The method for recycling and regenerating waste metal powder from 3D printing based on electrochemistry as described in claim 1, characterized in that, The electrochemical treatment device consists of a cavity, a positive electrode, a negative electrode, and a diaphragm. The positive and negative electrodes share the same electrochemical treatment solution, and the diaphragm covers the negative electrode. The positive electrode is a size-stabilized electrode, specifically one of the following: boron-doped diamond thin film electrode, titanium-based ruthenium-iridium electrode, titanium-based iridium-tantalum electrode, titanium-based ruthenium-indium-tin electrode, titanium-based tin-antimony oxide electrode, titanium-based titanium suboxide electrode, and titanium-based lead dioxide electrode; The negative electrode material includes at least one of a metallic material and a carbon material, wherein: the metallic material includes at least one of stainless steel, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, niobium, tantalum, zirconium, tungsten, cerium, aluminum, bismuth, rhenium, barium, osmium, tin, lead, gold, silver, platinum, palladium, iridium, rhodium, molybdenum, and ruthenium; the carbon material includes any one of graphite felt, carbon felt, graphite, glassy carbon, boron-doped diamond, activated carbon, graphene, carbon fiber, carbon nanotubes, and carbon sponge; The electrode shape includes any one of sheet, rod, filament, granular, sponge, mesh and porous structure. The constant temperature of the positive and negative electrode electrochemical treatment solution is 10℃~90℃, the electrode spacing is 1mm~100mm, and the positive and negative electrode area ratio is 1:10~10:

1. The diaphragm is at least one of ion exchange membrane and porous membrane. The ion exchange membrane is made of polybenzothiazole, polybenzimidazole, sulfonated polyethylene, polyethersulfone, sulfonated polypropylene, polyimide, polysulfone, perfluorosulfonic acid resin, polyether ether ketone, perfluorocarboxylic acid resin, or polyvinylidene fluoride resin. The porous membrane is made of porous fiber membrane, nonwoven membrane, or fiber paper made of polyethylene, polypropylene, polyvinyl chloride, nylon, polyester, polyvinylidene fluoride, polytetrafluoroethylene, or glass fiber.

7. The method for recycling and regenerating waste metal powder from 3D printing based on electrochemistry as described in claim 1, characterized in that, The electrochemical treatment process used adopts a two-step process of electrochemical oxidation + electrochemical reduction. The electrochemical oxidation process can be any one of constant current electro-oxidation, constant voltage electro-oxidation, and constant current pulse electro-oxidation, with an electro-oxidation time of 60 to 600 min. The electrochemical reduction process can be any one of constant current electro-reduction, constant voltage electro-reduction, and constant current pulse electro-reduction, with an electro-reduction time of 0 to 30 min.

8. The method for recycling and regenerating waste metal powder from 3D printing based on electrochemistry as described in claim 7, characterized in that, During constant voltage electro-oxidation, the voltage ranges from 1 to 100V; during constant current electro-oxidation, the current density, calculated based on the negative electrode working area, ranges from 10 to 500 mA / cm². 2 During constant current pulsed electro-oxidation, the current density calculated based on the negative electrode working area is 10–1000 mA / cm². 2 The frequency is 200–2000 Hz, and the duty cycle is 20%–80%. During constant-voltage electroreduction, the voltage ranges from 1 to 100V; during constant-current electroreduction, the current density calculated based on the negative electrode working area ranges from 1 to 50 mA / cm². 2 During constant current pulsed electrical reduction, the current density calculated based on the negative electrode working area is 1–100 mA / cm². 2 The frequency is 200–2000 Hz, and the duty cycle is 20%–80%.

9. The method for recycling and regenerating waste metal powder from 3D printing based on electrochemistry as described in claim 1, characterized in that, The electrochemical treatment solution is circulated through the surface of the metal powder in the chamber using a circulating pump, with a flow rate of 0–30 m³ / h. 3 / h.

10. The method for recycling and regenerating waste metal powder from 3D printing based on electrochemistry as described in claim 1, characterized in that, The electrochemically treated metal powder is then vacuum dried at a temperature of 50℃ to 400℃ for 0.5h to 10h.

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