Method for recycling nickel electroplating waste liquid

Abstract

The invention discloses a method for recycling nickel electroplating waste liquid, which is characterized in that COD (Chemical Oxygen Demand) and Fe < 2 + > in the waste electroplating liquid are removed by adopting an electrooxidation-H2O2 oxidation combined process; h2O2 is added into the electrooxidation pond, and the mass ratio of the added H2O2 to COD in the electroplating waste liquid is 2.1-2.5. Effective plating solution components such as nickel chloride, nickel sulfate and boric acid in the treated waste plating solution can be recycled, and recycling of the waste plating solution is achieved.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, specifically relating to a method for the resource recycling of nickel electroplating waste liquid. Background Technology

[0002] Nickel electroplating is a method of depositing a layer of nickel onto the surface of ferrous or non-ferrous metal parts through electrochemical action. It can be used as a surface coating, but is primarily used as a base coat for chromium plating to prevent corrosion and increase wear resistance, gloss, and aesthetics. It is widely used in the manufacturing industries of machinery, instruments, meters, medical devices, and household appliances. The workpiece is used as the cathode, and a pure nickel plate as the anode, which is then immersed in an electrolyte solution prepared with nickel sulfate, nickel chloride, and boric acid for electroplating.

[0003] Watt's plating solution is a commonly used electroplating solution, whose main components include nickel sulfate, nickel chloride, boric acid, and a small amount of additives. During the electroplating process, the inorganic components such as nickel sulfate, nickel chloride, and boric acid in the solution remain unchanged; however, the additives are organic substances and undergo chemical reactions such as oxidation and decomposition during the electroplating process. In addition, the iron on the steel plate surface also undergoes a trace oxidation reaction during electroplating to form Fe. 2+ Dissolves in electroplating solution, Fe 2+ Excessive concentration can affect the electroplating effect. Therefore, the composition of the electroplating solution changes after a period of use, thus affecting the electroplating effect. Regular replacement of the electroplating solution is necessary, resulting in waste plating solution.

[0004] The effective components in the waste plating solution, such as nickel chloride, nickel sulfate, and boric acid, remain unchanged; only the additives have changed, with a small increase in ferrous ions. If the organic matter and ferrous ions can be removed, and a small amount of organic additives are added, the waste plating solution can be recycled. To ensure the purity of the electroplating solution, no new substances should be introduced during the removal of organic matter and ferrous ions.

[0005] Chinese patent document with application number 201210368797.1 discloses an online circulating treatment system for zero discharge of nickel-containing electroplating wastewater, which includes: a pretreatment system, a filtration and permeation system and an evaporation and concentration system; the pretreatment system includes a raw water tank (1), a booster pump (2), an MBR membrane treatment device (3), a bag filter (4), an oil removal filter (5), and a security filter (6); the filtration and permeation system includes: an ultrafiltration device (7), a first high-pressure pump (8), a first-stage reverse osmosis unit (9), a first-stage intermediate water tank (10), a second high-pressure pump (11), a second-stage reverse osmosis unit (12), and a high-concentration nickel water collection tank (13); the evaporation and concentration system includes a solar water heater (14), an electric heater (15), a hot water storage tank (16), a circulating pump (17), a ring ladder multi-effect evaporation tower (18), and an ultra-high concentration nickel water collection tank (19). The equipment is well-integrated and highly automated, achieving a nickel recovery rate of up to 99.98% and a water reuse rate of up to 100%. It produces no secondary pollution and can thoroughly achieve zero discharge of nickel plating wastewater, which is of great significance to the sustainable development of the electroplating industry.

[0006] Chinese patent application number 201310345579.0 discloses an apparatus and method for recovering nickel from nickel-containing wastewater using a microbial electrolysis cell. The apparatus includes a microbial electrolysis cell, a data acquisition system, and a recording unit. The microbial electrolysis cell is a dual-chamber microbial electrolysis cell. The cell uses a conductive inert material as the anode electrode and a conductive inert material as the cathode electrode, connected by a titanium wire, a potentiostat, and a resistor. The data acquisition system is connected in parallel with the resistor, and the recording unit is connected to the data acquisition system. This invention provides a feasibility analysis and specific operating method for recovering nickel from nickel-containing wastewater using a microbial electrolysis cell, realizing the recovery of nickel from nickel-containing wastewater using a microbial electrolysis cell. Compared with traditional electrolytic methods for recovering nickel from water, this method significantly reduces energy consumption, reduces the use of chemical reagents, lowers costs, and avoids environmental pollution.

[0007] Chinese patent document with application number 201410301526.3 discloses a method for treating nickel-containing wastewater in the electroplating industry. The method for treating nickel-containing wastewater includes the following steps: (1) adding an oxidant to the nickel-containing wastewater under acidic conditions to carry out an oxidation reaction; (2) adding an alkali to the nickel-containing wastewater after the oxidation reaction in step (1) to make the nickel-containing wastewater alkaline, then allowing it to settle and collect the supernatant; (3) adding a precipitant and a flocculant to the supernatant in step (2) in sequence for co-precipitation, and the resulting final supernatant is the treated wastewater that can be discharged. The treatment method of the present invention is simple to operate, has stable effect, and the reagents used will not cause secondary pollution to the environment; the treatment method of the present invention utilizes the co-precipitation effect of flocculant and precipitate on the basis of secondary precipitation, which can ensure that the total nickel concentration of the treated nickel-containing wastewater can meet the discharge standards.

[0008] Chinese patent document application number 201410473920.5 discloses a nickel-containing wastewater treatment device, including a nickel-containing wastewater storage and input device, a nickel-containing wastewater pH adjustment tank, a pump system, an electrolysis device, and a control device, as well as a wastewater recycling treatment device. This invention also discloses the corresponding treatment method for the nickel-containing wastewater treatment device. In this invention, chemical nickel waste liquid and nickel-containing wastewater concentrate are added to the nickel-containing wastewater pH adjustment tank and mixed to adjust the pH value to 6-7. The pH-adjusted wastewater is then passed into an electrolysis tank and electrolyzed at 65-75℃ to recover elemental nickel. The nickel discharge concentration in the wastewater after electrolysis is below 0.02 g / L, and the recovery rate is above 97%. After electrolysis, the wastewater is further treated by reverse osmosis resin exchange, and the treated wastewater can be directly discharged or recycled.

[0009] Chinese patent document application number 201510136498.9 discloses a method and system for treating nickel-containing wastewater, which can ensure the stability of effluent quality. The method of this invention includes: discharging the nickel-containing wastewater into a complex-breaking reaction tank, adding bleach, discharging the effluent into a first pH adjustment tank, adding NaOH to adjust the pH value, discharging the effluent into a calcium salt reaction tank, adding CaO and DTC, discharging the effluent into a coagulation sedimentation tank, adding polyaluminum chloride and polyacrylamide, allowing it to settle, filtering to obtain the supernatant, discharging the supernatant into a second pH adjustment tank, adding H2SO4 solution, reacting the effluent, discharging the effluent into a Fenton reaction tank, adding H2O2 and FeSO4, discharging the effluent into a third pH adjustment tank, adding NaOH, then discharging into a Fenton sedimentation tank, adding polyaluminum chloride and polyacrylamide, and finally discharging the effluent into an ammonia nitrogen reaction tank, adding bleach. Summary of the Invention

[0010] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a method for the resource recycling of nickel electroplating waste liquid.

[0011] The technical problem it aims to solve can be addressed through the following technical solutions.

[0012] A method for the resource recovery and reuse of nickel electroplating waste liquid, characterized by the use of a combined electro-oxidation-H2O2 oxidation process to remove COD and Fe from the waste electroplating liquid. 2+ H2O2 was added to the electro-oxidation tank, and the mass ratio of the added H2O2 to the COD in the electroplating waste liquid was 2.1 to 2.5.

[0013] Furthermore, the operating parameters of the combined electro-oxidation and H2O2 oxidation process are: current density 2-6 A / dm³. 2 The hydraulic retention time is 24–48 hours; the coagulant used is anionic PAM, with a dosage of 3–5 ppm.

[0014] Preferably, H2O2 is added in batches, once every 1 to 2 hours.

[0015] Furthermore, the electro-oxidation process uses a high-efficiency composite electrode as the anode and a stainless steel electrode as the cathode.

[0016] Furthermore, the fabrication process of the high-efficiency composite electrode is as follows:

[0017] (1) Prepare the etched titanium plate;

[0018] (2) Plate a layer of nickel on the surface of the titanium substrate of the titanium plate;

[0019] (3) Using nickel-plated titanium plate as the anode and carbon as the cathode, PbO2 active oxide layer is prepared on the nickel-plated titanium plate electrode by electrodeposition to obtain a high-efficiency Ti / PbO2 composite electrode.

[0020] Preferably, in step (1), during etching, a titanium plate is used as the anode substrate. The titanium plate is placed in a NaOH solution with a mass concentration of 3-5%, and 100-300 mg / L of sodium dodecylbenzenesulfonate is added to the NaOH solution. The temperature is controlled at 65-75°C and held for 40-60 minutes. During this period, the plate is brushed and cleaned with deionized water. This removes the oil stains from the surface of the titanium plate. Then, the cleaned titanium plate is placed in a mixed solution of HNO3 and HF, where the mass concentrations of HNO3 and HF are 10-20% and 1-5%, respectively. The temperature is controlled at 50-60°C and held for 60-80 minutes. A titanium plate with a metallic luster and a grayish-brown surface is obtained.

[0021] Preferably, before the treatment in step (2), the etched titanium plate is stored in anhydrous ethanol, rinsed clean and dried before use.

[0022] Preferably, in step (2), the plating solution formulation is: NiSO4 150~200g / L, H2SO4 6~8g / L. The nickel plating process parameters are: titanium substrate as anode, carbon as cathode; plating temperature 50~70℃, current density 5~10A / dm³. 2 Electroplating time: 5-10 minutes.

[0023] Preferably, in step (3), the electrodeposition solution composition is: 0.1–0.2 mol / L lead nitrate (Pb(NO3)2), 0.5–0.6 mol / L sulfamic acid (NH2SO3H), and 0.03–0.04 mol / L sodium dodecyl sulfate (C 12 H 25 (SO4Na); electrodeposition temperature 50–70℃, current density 10–15 A / dm³ 2 Electroplating time is 60-90 minutes.

[0024] Preferably, the composition of the electroplating waste liquid is as follows: Ni 2+ 60~80g / L, Cl - 15~20g / L, SO4 2- 80~100g / L, B6~7g / L, COD5~10g / L, Fe 2+ 300–2000 mg / L, pH 4–4.5.

[0025] The above-mentioned method for the resource recovery and reuse of nickel plating waste liquid involves treating the waste liquid using a combined electro-oxidation-H2O2 oxidation process, which reduces COD and Fe content, which are detrimental to the reuse of the waste plating liquid. 2+ The waste electroplating solution is effectively removed, while the effective components such as NiCl2, NiSO4, and H3BO3 remain largely unchanged. After being re-prepared with additives, it can be returned to the unit for recycling, achieving resource utilization of the waste electroplating solution. This invention allows for the recycling of effective plating solution components such as nickel chloride, nickel sulfate, and boric acid from the waste electroplating solution, realizing resource utilization of the waste electroplating solution. This invention has both economic and environmental benefits, demonstrating significant social and environmental advantages. Detailed Implementation

[0026] The specific embodiments of the present invention will be further described in detail below.

[0027] The composition of Watt's waste electroplating solution is as follows: Ni 2+ 60~80g / L, Cl - 15~20g / L, SO4 2- 80~100g / L, B6~7g / L, COD5~10g / L, Fe 2+ 300–2000 mg / L, pH 4–4.5.

[0028] A combined electro-oxidation-H2O2 oxidation process was used to remove COD and Fe from waste electroplating solutions. 2+ The electro-oxidation process uses a high-efficiency composite electrode as the anode and a stainless steel electrode as the cathode. During electrolysis, strong oxidizing substances such as ·OH, H₂O₂, and O₃ are generated. These strong oxidizing substances can decompose organic pollutants in the waste electroplating solution into small-molecule organic matter, CO₂, and water. To enhance the removal of organic matter, H₂O₂ is added to the electro-oxidation tank. H₂O₂, as a strong oxidant, can decompose organic matter and simultaneously remove Fe. 2+ Oxidized to Fe 3+ Fe 3+ It can form flocs, and under the promotion of coagulants, form large particle precipitates, making Fe... 2+ It has been removed.

[0029] Operating parameters of the combined electro-oxidation and H2O2 oxidation process: current density 2-6 A / dm³ 2 The hydraulic retention time is 24–48 h; the ratio of added H2O2 to COD is 2.1–2.5. To improve the utilization rate of H2O2, H2O2 is added in batches, once every 1–2 h; the coagulant is anionic PAM, with a dosage of 3–5 ppm.

[0030] After treatment by a combined electro-oxidation and H2O2 oxidation process, the COD and Fe in the waste electroplating solution... 2+ The substances can be removed, while the NiCl2, NiSO4, and H3BO3 remain largely unchanged. After reconfiguring the additives, they can be returned to the unit for recycling.

[0031] The fabrication process for high-efficiency composite electrodes is as follows:

[0032] The anode substrate is a titanium plate. The titanium plate is placed in a 3-5% NaOH solution, with 100-300 mg / L of sodium dodecylbenzenesulfonate added. The temperature is controlled at 65-75°C and held for 40-60 minutes, during which time it is brushed. After removal, it is cleaned with deionized water to remove oil stains from the titanium plate surface. Then, the cleaned titanium plate is placed in a mixed solution of 10-20% HNO3 and 1-5% HF, with the temperature controlled at 50-60°C and held for 60-80 minutes. This process further removes oxides from the titanium plate surface. This process is called etching. The etched titanium plate has a metallic luster and a grayish-brown surface. This treatment removes oil stains and oxides from the titanium plate surface and also makes its bonding with the coating stronger. Finally, the etched titanium plate is removed, rinsed with deionized water, and stored in anhydrous ethanol. Rinse thoroughly with pure water before use and dry in an oven at 105℃.

[0033] To prevent the titanium substrate from being oxidized and passivated, and to enhance the adhesion of the PbO2 coating to the substrate and prevent it from detaching, an intermediate coating is added between the titanium substrate and the PbO2 coating, which can improve the stability of the Ti / PbO2 composite electrode. Plating a layer of Ni on the surface of the titanium substrate yields a fine-grained PbO2 coating, resulting in a very smooth electrode surface. The nickel plating formula is: NiSO4 150–200 g / L, H2SO4 6–8 g / L. The nickel plating process parameters are: titanium substrate as anode, carbon as cathode; plating temperature 50–70℃, current density 5–10 A / dm³. 2 Electroplating time is 5-10 minutes. After nickel plating, rinse thoroughly with pure water and dry in an oven at 105℃.

[0034] After drying, the electrode was used to prepare a PbO2 active oxide layer using electrodeposition. The active oxide layer was prepared using electrodeposition, with a nickel-titanium plate as the anode and carbon as the cathode. The electrodeposition solution consisted of: 0.1–0.2 mol / L lead nitrate (Pb(NO3)2), 0.5–0.6 mol / L sulfamic acid (NH2SO3H), and 0.03–0.04 mol / L sodium dodecyl sulfate (C). 12 H 25 (SO4Na). Electrodeposition temperature 50–70℃, current density 10–15 A / dm³ 2 Electroplating time is 60–90 min. After electrodeposition, the electrodepositer is rinsed with pure water and dried in an oven at 105 °C to obtain a high-efficiency Ti / PbO2 composite electrode.

[0035] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the content of the invention is not limited to the following embodiments.

[0036] Example 1

[0037] The composition of Watt's waste electroplating solution is as follows: Ni 2+ 68g / L, Cl - 17g / L, SO4 2- 92g / L, B7.2g / L, COD7.2g / L, Fe 2+ 850 mg / L, pH 4.3.

[0038] Operating parameters of the combined electro-oxidation and H2O2 oxidation process: current density 4A / dm 2 The hydraulic retention time was 36 hours; the ratio of added H2O2 to COD was 2.3; H2O2 was added in batches, every 1.5 hours, at a dosage of 0.69 g / L each time; anionic PAM was used as the coagulant aid, with a dosage of 4 ppm. After treatment by the combined electro-oxidation-H2O2 oxidation process, the effluent COD was 0.65 g / L, and Fe... 2+ <0.05mg / L, Fe 3+ 26 mg / L.

[0039] The fabrication process for high-efficiency composite electrodes is as follows:

[0040] The anode substrate is a titanium plate. The titanium plate is placed in a 4% (w / w) NaOH solution, with 200 mg / L sodium dodecylbenzenesulfonate added. The temperature is controlled at 70℃ and maintained for 50 minutes, during which time it is brushed. After removal, it is rinsed thoroughly with deionized water. Then, the cleaned titanium plate is placed in a mixed solution of 15% (w / w) HNO3 and 3% HF, and the temperature is controlled at 55℃ and maintained for 70 minutes. The etched titanium plate is then removed, rinsed thoroughly with deionized water, and stored in anhydrous ethanol. Before use, it is rinsed with pure water and dried in an oven at 105℃.

[0041] The nickel plating formula is: NiSO4 170 g / L, H2SO4 7 g / L. The nickel plating process parameters are: titanium substrate as anode, carbon as cathode; plating temperature 60℃, current density 8 A / dm³. 2 Electroplating time: 8 minutes. After nickel plating, rinse thoroughly with pure water and dry in an oven at 105℃.

[0042] After drying, the electrode was used to prepare a PbO2 active oxide layer using electrodeposition. The active oxide layer was prepared using electrodeposition, with a nickel-titanium plate as the anode and carbon as the cathode. The electrodeposition solution consisted of: 0.15 mol / L lead nitrate (Pb(NO3)2), 0.55 mol / L sulfamic acid (NH2SO3H), and 0.035 mol / L sodium dodecyl sulfate (C). 12 H 25 (SO4Na). Electrodeposition temperature 60℃, current density 12A / dm³ 2 Electroplating time was 75 min. After electrodeposition, the electrodepositer was rinsed with pure water and dried in an oven at 105℃ to obtain a high-efficiency Ti / PbO2 composite electrode.

[0043] Example 2

[0044] The composition of Watt's waste electroplating solution is as follows: Ni 2+ 61g / L, Cl - 15g / L, SO4 2- 83g / L, B6.3g / L, COD5.3g / L, Fe 2+ 350 mg / L, pH 4.5.

[0045] Operating parameters of the combined electro-oxidation and H2O2 oxidation process: current density 2A / dm³ 2 The hydraulic retention time was 24 hours; the ratio of added H2O2 to COD was 2.1; H2O2 was added in batches, once every 1 hour, at a dosage of 0.46 g / L each time; anionic PAM was used as the coagulant aid, with a dosage of 3 ppm. After treatment by the combined electro-oxidation-H2O2 oxidation process, the COD in the effluent was 0.39 g / L, and the Fe...2+ <0.05mg / L, Fe 3+ 23 mg / L.

[0046] The fabrication process for high-efficiency composite electrodes is as follows:

[0047] The anode substrate is a titanium plate. The titanium plate is placed in a 3% (w / w) NaOH solution, with 100 mg / L sodium dodecylbenzenesulfonate added. The temperature is controlled at 75℃ and maintained for 40 minutes, during which time it is brushed. After removal, it is rinsed thoroughly with deionized water. Then, the cleaned titanium plate is placed in a mixed solution of 10% (w / w) HNO3 and 35% HF, and the temperature is controlled at 50℃ and maintained for 80 minutes. The etched titanium plate is then removed, rinsed thoroughly with deionized water, and stored in anhydrous ethanol. Before use, it is rinsed with pure water and dried in an oven at 105℃.

[0048] The nickel plating formula is: NiSO4 150 g / L, H2SO4 6 g / L. The nickel plating process parameters are: titanium substrate as anode, carbon as cathode; plating temperature 70℃, current density 10 A / dm³. 2 Electroplating time: 5 minutes. After nickel plating, rinse thoroughly with pure water and dry in an oven at 105℃.

[0049] After drying, the electrode was used to prepare a PbO2 active oxide layer using electrodeposition. The active oxide layer was prepared using electrodeposition, with a nickel-titanium plate as the anode and carbon as the cathode. The electrodeposition solution consisted of: 0.2 mol / L lead nitrate (Pb(NO3)2), 0.5 mol / L sulfamic acid (NH2SO3H), and 0.03 mol / L sodium dodecyl sulfate (C). 12 H 25 (SO4Na). Electrodeposition temperature 70℃, current density 10A / dm³ 2 Electroplating time was 90 min. After electrodeposition, the electrodepositer was rinsed with pure water and dried in an oven at 105℃ to obtain a high-efficiency Ti / PbO2 composite electrode.

[0050] Example 3

[0051] The composition of Watt's waste electroplating solution is as follows: Ni 2+ 78 g / L, Cl- 19 g / L, SO4 2- 95g / L, B7.5g / L, COD9.6g / L, Fe 2+ 1800 mg / L, pH 4.1.

[0052] Operating parameters of the combined electro-oxidation and H2O2 oxidation process: current density 5A / dm³ 2The hydraulic retention time was 48 hours; the ratio of added H2O2 to COD was 2.5; H2O2 was added in batches, once every 2 hours, at a dosage of 1 g / L each time; anionic PAM was used as the coagulant aid, with a dosage of 5 ppm. After treatment by the combined electro-oxidation-H2O2 oxidation process, the COD in the effluent was 0.68 g / L, and the Fe... 2 + <0.05mg / L, Fe 3+ 35 mg / L.

[0053] The fabrication process for high-efficiency composite electrodes is as follows:

[0054] The anode substrate is a titanium plate. The titanium plate is placed in a 5% NaOH solution, with 300 mg / L sodium dodecylbenzenesulfonate added. The temperature is controlled at 65℃ and maintained for 60 minutes, during which time it is brushed. After removal, it is rinsed thoroughly with deionized water. Then, the cleaned titanium plate is placed in a mixed solution of 20% HNO3 and 1% HF, and the temperature is controlled at 60℃ and maintained for 60 minutes. The etched titanium plate is then removed, rinsed thoroughly with deionized water, and stored in anhydrous ethanol. Before use, it is rinsed with pure water and dried in an oven at 105℃.

[0055] The nickel plating formula is: NiSO4 200 g / L, H2SO4 8 g / L. The nickel plating process parameters are: titanium substrate as anode, carbon as cathode; plating temperature 50℃, current density 5 A / dm³. 2 Electroplating time: 10 minutes. After nickel plating, rinse thoroughly with pure water and dry in an oven at 105℃.

[0056] After drying, the electrode was used to prepare a PbO2 active oxide layer using electrodeposition. The active oxide layer was prepared using electrodeposition, with a nickel-titanium plate as the anode and carbon as the cathode. The electrodeposition solution consisted of: 0.2 mol / L lead nitrate (Pb(NO3)2), 0.6 mol / L sulfamic acid (NH2SO3H), and 0.03 mol / L sodium dodecyl sulfate (C). 12 H 25 (SO4Na). Electrodeposition temperature 50℃, current density 15A / dm³ 2 Electroplating time was 60 min. After electrodeposition, the electrodepositer was rinsed with pure water and dried in an oven at 105℃ to obtain a high-efficiency Ti / PbO2 composite electrode.

Claims

1. A method for resource recycling of electroplating nickel electroplating waste solution, characterized in that, Removal of COD and Fe in waste electroplating solution by electro-oxidation-H2O2 oxidation combined process 2+ ; H2O2 is added in the electro-oxidation tank, and the mass ratio of H2O2 to COD in the electroplating waste liquid is 2.1-2.

5.

2. The method for recycling electroplating nickel electroplating waste solution according to claim 1, characterized in that, The electric oxidation-H2O2 oxidation combined process operating parameters are: current density 2-6 A / dm 2 , hydraulic retention time 24-48 h; coagulant aid is anionic PAM, dosage 3-5 ppm.

3. The method for resource recycling of electroplating nickel electroplating waste solution according to claim 1 or 2, characterized in that, H2O2 is added in batches, and is added once every 1-2 hours.

4. The method for recycling electroplating nickel electroplating waste solution according to claim 1, characterized in that, The electro-oxidation process uses a high-efficiency composite electrode as an anode and a stainless steel electrode as a cathode.

5. The method for recycling electroplating nickel electroplating waste solution according to claim 4, characterized in that, The preparation process of the high-efficiency composite electrode is as follows: (1) prepare an etched titanium plate; (2) plate a layer of nickel on the surface of the titanium plate; (3) use the plated titanium plate as an anode, carbon as a cathode, and adopt an electrodeposition method to prepare a PbO2 active oxidation layer on the plated titanium plate electrode to obtain a high-efficiency Ti / PbO2 composite electrode.

6. The method for recycling electroplating nickel electroplating waste solution according to claim 5, characterized in that, In step (1), when etching, the titanium plate is used as an anode substrate, and the titanium plate is placed in a NaOH solution with a mass concentration of 3-5%, 100-300 mg / L of sodium dodecyl benzene sulfonate is added to the NaOH solution, the temperature is controlled at 65-75℃, and the titanium plate is brushed during constant temperature for 40-60 min, and then the titanium plate is cleaned with deionized water, so that the oil stains on the surface of the titanium plate can be removed; then, the cleaned titanium plate is placed in a mixed solution composed of HNO3 and HF, the mass concentrations of HNO3 and HF in the mixed solution are 10-20% and 1-5% respectively, the temperature is controlled at 50-60℃, and the titanium plate is kept at constant temperature for 60-80 min; thus, the titanium plate with a metallic luster and a grayish surface is obtained.

7. The method for resource recycling of electroplating nickel electroplating waste solution according to claim 5 or 6, characterized in that, Before step (2), the etched titanium plate is stored in anhydrous ethanol, and is cleaned and dried before use.

8. The method for recycling electroplating nickel electroplating waste solution according to claim 5, characterized in that, In step (2), the plating solution is: NiSO4 150-200 g / L, H2SO4 6-8 g / L. The process parameters for nickel plating are: titanium substrate as anode, carbon as cathode; plating temperature 50-70 °C, current density 5-10 A / dm 2 , plating time 5-10 min.

9. The method for recycling electroplating nickel electroplating waste solution according to claim 5, characterized in that, In step (3), the composition of the electrodeposition solution of the electrodeposition method: 0.1-0.2 mol / L lead nitrate (Pb(NO3)2), 0.5-0.6 mol / L sulfamic acid (NH2SO3H), 0.03-0.04 mol / L sodium dodecyl sulfate (C 12 H 25 SO4Na); electrodeposition temperature 50-70℃, current density 10-15 A / dm 2 , plating time 60-90 min.

10. The method for recycling electroplating nickel electroplating waste solution according to claim 1, characterized in that, The composition of the electroplating waste solution is as follows: Ni 2+ 60-80 g / L, Cl - 15-20 g / L, SO4 2- 80-100 g / L, B 6-7 g / L, COD 5-10 g / L, Fe 2+ 300-2000 mg / L, pH 4-4.5.