A process, apparatus and application for treating chemical plating waste liquid

Abstract

This invention relates to the field of wastewater treatment technology, and more particularly to a process, apparatus, and application for treating chemical plating wastewater. The treatment steps include: sequentially passing the chemical plating wastewater to be treated through a protective filter and a precision filter for filtration; then passing it through a deactivation storage tank to reduce the activity of the wastewater; subsequently passing it through an ultra-precision filter, a pH adjustment tank, an ion exchange resin, and an activated carbon adsorption device for further treatment; and collecting the discharged products to obtain the final product. The core of this wastewater treatment process is a multi-step membrane separation technique that effectively separates heavy metal ions and complexing agents from the wastewater system without damaging the overall chemical plating system, achieving recycling while removing impurities.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to a process, apparatus and application for treating chemical plating waste liquid. Background Technology

[0002] With the rapid development of industry, electroless plating, as a surface treatment process that can effectively enhance the surface properties of substrate materials, is being applied in increasingly wider fields. However, the development of manufacturing and the widespread use of electroless plating have also led to the generation of large amounts of electroless plating wastewater. Electroless plating solutions contain large amounts of heavy metal ions (such as copper, iron, nickel, and cobalt ions) that combine with complexing agents. Direct discharge of these solutions would cause environmental pollution and resource waste. Therefore, treating electroless plating wastewater containing heavy metal ions is crucial for wastewater treatment in the industry.

[0003] Currently, the common treatment method involves completely separating heavy metal ions from water to meet discharge standards. This primarily uses chemical reagents (such as ferrous sulfate) to break down metal complexes, followed by the addition of an alkaline solution to precipitate the metal ions. Flocculants are then added for flocculation, and filtration is used to separate the metal ions from the wastewater. This complex process ensures the wastewater meets discharge standards. However, this method is complex, costly, and has limited heavy metal recovery, leading to resource waste. Furthermore, existing technologies struggle to achieve resource recycling in the treatment of chemical plating wastewater, resulting in significant resource waste.

[0004] Chinese patent CN 110451688 A discloses a method for treating PCB chemical copper plating wastewater. This method removes copper from the wastewater through a series of steps including complex breaking precipitation and Fenton oxidation precipitation, ensuring a stable copper content in the wastewater that meets effluent requirements. However, this invention disrupts the chemical copper plating solution system and cannot effectively recover the complexing agent. The precipitated copper ions contain numerous impurities, resulting in significant resource waste. Chinese patent CN 112479458A discloses a method for treating PCB chemical copper plating wastewater. This method involves adding a certain proportion of chemicals for complex breaking, flocculation, concentration, and crystallization, achieving the technical requirement of simultaneously recovering copper and the complexing agent. However, this invention also disrupts the chemical copper plating solution system, preventing reuse; furthermore, this invention is only applicable when the complexing agent is an EDTA system, exhibiting significant limitations.

[0005] Against this backdrop, providing a simple and efficient process for treating chemical plating waste liquid and enabling resource recycling has become a pressing technical problem to be solved in this field. Summary of the Invention

[0006] The purpose of this invention is to provide a chemical plating wastewater treatment process to solve the problems of complex processes and high costs associated with existing wastewater treatment methods. On the one hand, this invention can reliably achieve near-zero emissions of heavy metals through membrane separation technology, acid-base neutralization, and degradation of organic pollutants, with all emission indicators meeting national emission standards. On the other hand, this treatment process is applicable to various complexing agent systems, enabling the simultaneous recovery and reuse of heavy metal ions and complexing agents without damaging the overall chemical plating system.

[0007] The first aspect of the present invention provides a chemical plating waste liquid treatment process, the treatment steps of which include: passing the chemical plating waste liquid to be treated sequentially through a protective filter and a precision filter for filtration treatment, then passing it through a deactivation storage tank to reduce the activity of the chemical plating waste liquid, and then passing it sequentially through an ultra-precision filter, a pH adjustment tank, an ion exchange resin, and an activated carbon adsorption device for treatment, and collecting the discharged products to obtain the final product.

[0008] 1) Protective filter treatment:

[0009] The wastewater to be treated undergoes the first step of filtration through a protective filter. The microporous membrane of the protective filter intercepts and adsorbs impurities and turbidity in the chemical plating wastewater.

[0010] Preferably, the protective filter is provided with a first filter membrane, the pore size of which is 1-100μm; more preferably 1-20μm.

[0011] Preferably, the filter material of the first filter membrane is at least one of cotton core, polypropylene, polytetrafluoroethylene, cellulose acetate, ceramic, activated carbon, polyethersulfone, mixed fiber resin, polyamide, and polyvinylidene fluoride.

[0012] 2) Precision filter treatment:

[0013] The chemical plating waste liquid discharged from the protective filter membrane undergoes a second filtration process. The chemical plating solution is protected by a precision filter membrane, which removes minute impurities without damaging the complexing agent and metal ion structure in the solution, ensuring that the complexation system retains its macromolecular structure. This results in a second filtration filtrate.

[0014] Preferably, the precision filter is provided with a second filter membrane, the pore size of which is 1-500 nm; more preferably, it is 1-50 nm.

[0015] Preferably, the filter material of the second filter membrane is at least one of polypropylene, polytetrafluoroethylene, cellulose acetate, ceramic, and activated carbon.

[0016] 3) Deactivation storage tank treatment:

[0017] The filtrate, after being processed by the protective filter and the precision filter, is fed into the deactivation storage tank, which is connected to an air pump to reduce the activity of the chemical plating solution.

[0018] Preferably, the deactivation storage tank has a built-in cooling device.

[0019] Preferably, the capacity of the deactivation storage tank is 50-500L.

[0020] Preferably, the tank body of the deactivation storage tank is made of at least one of PVC (polyvinyl chloride), PP (polypropylene), PE (polyethylene), PTFE (polytetrafluoroethylene), FRP (fiber reinforced plastic, also known as fiberglass), acrylic material, and glass.

[0021] 4) Ultra-precision filter treatment:

[0022] After deactivation treatment, the chemical plating wastewater enters the third filtration system, where a nanofiltration membrane is used to effectively separate the chemical plating system. During this filtration step, the complexing agent and the large molecular structure of the heavy metal complexing system are intercepted, while inorganic salts and other small molecular structures in the chemical plating solution are discharged. The intercepted large molecules of the complexing system can be returned to the original plating bath for reuse. This process greatly reduces the amount of wastewater discharged. No chemical additives are added to the separation system. The entire filtration process uses physical methods to separate the complexing agent and heavy metal ions from the wastewater system, achieving the technical effects of emission reduction, reuse, and pollution reduction.

[0023] Preferably, the ultra-precision filter is provided with a third filter membrane, the pore size of which is 0.1-50nm; more preferably 0.2-5nm.

[0024] Preferably, the filter material of the third filter membrane is at least one of a composite nanofiltration membrane or a reverse osmosis membrane.

[0025] The composite nanofiltration membranes can be categorized as nanofiltration membranes and their composites made of cellulose acetate, sulfonated polysulfone, sulfonated polyethersulfone, polyvinyl alcohol, polyamide, alumina, titanium dioxide, zirconium oxide, etc., polyester composite nanofiltration membranes, polyethersulfone / polyamide composite nanofiltration membranes, polysulfone / polyamide composite nanofiltration membranes, polyimide / polyamide composite nanofiltration membranes, polyetheretherketone / polyamide composite nanofiltration membranes, nanomaterial-modified composite nanofiltration membranes, porous support layer / separation layer composite nanofiltration membranes and their modified composite nanofiltration membranes.

[0026] The reverse osmosis membrane can be listed as cellulose acetate and its derivatives reverse osmosis membrane, polyamide and its derivatives reverse osmosis membrane, polyethersulfone and its derivatives reverse osmosis membrane, polyhydrazide and its derivatives reverse osmosis membrane and its composite reverse osmosis membrane, etc.

[0027] 5) pH adjustment tank treatment:

[0028] The chemical plating waste liquid, from which the complexing agent and heavy metal ions have been separated, continues to enter the pH adjustment tank. At this point, an appropriate amount of pH adjuster is added to adjust the pH of the chemical plating waste liquid to 7-8.

[0029] Preferably, the pH adjuster is at least one of an aqueous solution of sulfuric acid, hydrochloric acid, boric acid, citric acid, sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate, and sodium bicarbonate.

[0030] Preferably, the capacity of the pH adjustment tank is 50-500L.

[0031] Preferably, the pH adjustment tank is made of at least one of PVC, PP, PE, PTFE, FRP, acrylic material, and glass.

[0032] 6) Ion exchange resin treatment:

[0033] After the pH of the chemical plating waste liquid is adjusted in the pH adjustment tank, it enters the ion exchange resin device. This ion exchange resin filtration device can adsorb metal ions and complexes that were not completely reused in the ultra-precision filter, so that heavy metal ions and complexes are completely separated from the filtrate. After treatment by the ion exchange resin device, most of the impurities in the filtrate are removed.

[0034] Preferably, the ion exchange resin is selected from strong acid cation exchange resins, weak acid cation exchange resins, chelating resins, redox resins, novel metal ion exchange resins (copper, palladium, nickel and their mixed metals) and their composite ion exchange resins.

[0035] More preferably, the strong acid cation exchange resin is a macroporous strong acid ion exchange resin.

[0036] 7) Treatment by activated carbon adsorption device:

[0037] The filtrate, after being filtered by the ion exchange resin system, is then fed into an activated carbon adsorption device. This filtration system can completely separate the organic impurities in the filtrate, resulting in a pure filtrate.

[0038] Preferably, the activated carbon adsorption device is provided with an activated carbon adsorption membrane, and the material of the activated carbon adsorption membrane is activated carbon material, such as one or more of pure activated carbon, modified activated carbon, activated carbon fiber, and modified activated carbon fiber.

[0039] Preferably, the pore size of the activated carbon adsorption membrane is 1-100 nm; more preferably, it is 10-50 nm.

[0040] The wastewater treatment process of this invention utilizes a multi-step membrane separation technique to effectively separate heavy metal ions and complexing agents without disrupting the overall chemical plating system, achieving recycling while removing impurities. The core of this invention involves using filtration membranes (including but not limited to microfiltration, ultrafiltration, nanofiltration, composite nanofiltration, and reverse osmosis membranes) to filter the chemical plating solution, retaining complexes and large molecules such as heavy metals for reuse. Any treatment method employing this principle is considered part of this invention. Furthermore, the wastewater treatment process of this invention combines membrane separation technology, acid-base neutralization, and activated carbon adsorption. This simple process achieves zero discharge of heavy metal ions, complexes, and other pollutants. First, the chemical plating solution is filtered through a membrane of a specific particle size to separate complexes and large molecules such as heavy metals for reuse. The diverted wastewater is then treated with acid-base neutralization, ion exchange, and activated carbon adsorption to remove small molecule pollutants. This invention utilizes purely physical methods to efficiently and thoroughly purify electroless plating wastewater without the need for external chemical reagents, representing a significant technological advancement in both filtration effectiveness and practicality. The electroless plating wastewater treated by this invention meets all national emission standards and can be widely applied.

[0041] Preferably, the chemical plating waste liquid originates from waste liquid generated during chemical copper plating, chemical nickel plating, chemical gold plating, chemical tin plating, chemical cobalt plating, chemical silver plating, chemical palladium plating, chemical iron plating, chemical zinc plating, chemical plating, chemical lead plating, chemical aluminum plating, chemical scandium plating, chemical titanium plating, chemical rhodium plating, and various metal alloys.

[0042] Preferably, the electroless plating waste liquid can also be derived from the waste liquid generated by electroless copper plating, including horizontal copper plating systems and gantry copper plating systems.

[0043] The heavy metal ions that can be separated by this invention include, but are not limited to, copper ions, nickel ions, tin ions, gold ions, palladium ions, mercury ions, palladium ions, iron ions, silver ions, cobalt ions, scandium ions, titanium ions, and rhodium ions, and can also separate one or more of the complexes / complexes containing the above-mentioned heavy metal ions.

[0044] Preferably, the heavy metal ions are mainly for reducing the emission of copper ions, which include monovalent copper, divalent copper, and their copper-containing complexes / complexes.

[0045] The complexing agents that can be separated by the present invention include, but are not limited to, compounds containing at least one of an amine group, a carboxyl group, a thiol group, or a hydroxyl group.

[0046] Examples of complexing agents include citric acid, pyrophosphate, EDTA (ethylenediaminetetraacetic acid), lactic acid, tartaric acid and its salts, sodium salicylate, sodium ethylenediaminetetraacetic acid, hypochlorous acid and its alkali metal salts, gluconic acid, gluconate, triethanolamine, modified ethylenediaminetetraacetic acid, S,S-ethylenediaminedisuccinic acid, glycine, malic acid, malonic acid, succinic acid, succinic acid, glycolic acid, aminoacetic acid, HEDP (hydroxyethylidene diphosphonic acid), ATMP (aminotrimethylphosphonic acid), etc.

[0047] The wastewater treatment process provided by this invention can be applied to the treatment of chemical plating wastewater in different fields, enabling zero discharge of heavy metal ions and pollutants, reducing pollution and resource waste, and is of great significance to the development of industrial environmental protection.

[0048] The second aspect of the present invention provides a chemical plating wastewater treatment device, the structure of which includes a protective filter, a precision filter, a deactivation storage tank, an ultra-precision filter, a pH adjustment tank, an ion exchange resin, and an activated carbon adsorption device connected in sequence.

[0049] Preferably, the chemical plating waste liquid treatment device further includes a high-pressure pump, which is located between 1) the deactivation storage tank and the ultra-precision filter; and 2) the pH adjustment tank and the ion exchange resin.

[0050] Preferably, the chemical plating waste liquid treatment device further includes a booster pump, and when the treatment device treats the waste liquid, the waste liquid to be treated is transported to the protective filter through the booster pump.

[0051] The components of the processing device are tightly connected by pipes.

[0052] The material of the pipe is not particularly limited, as long as it can achieve the purpose of transmission. For example, PVC, PP, PE, PTFE, FRP, PVDF (polyvinylidene fluoride) can be used.

[0053] The third aspect of the present invention provides applications of the processing technology or processing apparatus described above, specifically in the fields of electronics and electrical industry, automotive industry, aerospace industry, medical device industry, powder metallurgy industry, and machinery manufacturing.

[0054] Beneficial effects:

[0055] This invention provides a chemical plating wastewater treatment process and its application, which has the following advantages:

[0056] (1) The wastewater treatment process of the present invention is based on a multi-step membrane separation technology to effectively separate heavy metal ions and complexing agents from the waste liquid system without damaging the overall chemical plating system, thereby achieving the effect of recycling while removing impurities.

[0057] (2) The present invention first filters the chemical plating solution through a filter membrane with a specific particle size to separate complexes and heavy metals and other macromolecular substances for reuse. The waste liquid after throttling is treated with acid-base neutralization, ion exchange, activated carbon adsorption and other methods to remove small molecule pollutants and impurities, which can effectively remove heavy metal ions and complexing agents from various chemical plating waste liquids.

[0058] (3) This invention relies entirely on physical means and can efficiently and thoroughly purify chemical plating waste liquid without the need for external chemical reagents; it has made significant technological progress in both filtration effect and practicality, and has extremely high practicality.

[0059] (4) This invention enables the simultaneous recycling of heavy metal ions and complexing agents without damaging the overall chemical plating system, thus avoiding resource waste.

[0060] (5) The waste liquid treatment process provided by the present invention can be applied to the chemical plating wastewater treatment process in different fields, so that heavy metal ions and their pollutants are close to zero discharge, reducing pollution and resource waste, which is of great significance to the development of industrial environmental protection.

[0061] (6) The treatment and reuse process of the present invention can be applied to various chemical plating waste liquids on the market, achieving excellent purification effect and strong technical applicability. Attached Figure Description

[0062] Figure 1 Schematic diagram of the processing equipment in Example 1 Detailed Implementation

[0063] Note: The units involved in this invention are explained as follows: min: minute; ms: millisecond; um: micrometer; ppm: parts per million; ppb: parts per billion; ℃: degree Celsius; g / L: gram per liter; A: ampere; dm: decimeter; DI: deionized; wt%: weight percentage; M: molar concentration (moL / L); N: mass concentration (g / L). Unless otherwise specified, the reagents, equipment, and materials described in the examples are all commercially available.

[0064] Example

[0065] The first aspect of this embodiment provides a chemical plating waste liquid treatment process, the treatment steps of which include: passing the chemical plating waste liquid to be treated sequentially through a protective filter and a precision filter for filtration treatment, then passing it through a deactivation storage tank to reduce the activity of the chemical plating waste liquid, and then sequentially passing it through an ultra-precision filter, a pH adjustment tank, an ion exchange resin, and an activated carbon adsorption device for treatment, and collecting the discharged products to obtain the final product.

[0066] The protective filter is equipped with a first filter membrane, specifically a PP cotton core filter membrane with a pore size of 5μm; sourced from Qinzhiyuan Environmental Protection Technology Co., Ltd.

[0067] The precision filter is equipped with a second filter membrane, specifically a ceramic filter membrane with a pore size of 5nm; the model is Delemil DED100.

[0068] The deactivation storage tank is connected to an air pump to reduce the activity of the chemical plating solution.

[0069] The deactivation storage tank has a built-in cooling and temperature reduction device.

[0070] The air pump has a pumping power of 35W and a displacement of 65L / min.

[0071] The cooling device is set to 24-26℃.

[0072] The deactivation storage tank has a capacity of 100L.

[0073] The deactivation storage tank is made of PVC.

[0074] The ultra-precision filter is equipped with a third filtration membrane, specifically a polyimide / polyamide composite nanofiltration membrane with a pore size of 0.5 nm; this filtration membrane is a DuPont FilmTec membrane. TM Nanofiltration membrane products are provided by DuPont China Group Co., Ltd.

[0075] During the pH adjustment tank treatment, the chemical plating waste liquid from which the complexing agent and heavy metal ions have been separated continues to enter the pH adjustment tank. At this time, a pH adjuster is added to adjust the pH of the chemical plating waste liquid to 7.5±0.5.

[0076] The pH adjuster is an aqueous solution of sulfuric acid.

[0077] The pH adjustment tank has a capacity of 100L.

[0078] The pH adjustment tank is made of PVC.

[0079] The ion exchange resin is selected from the strong acid cation exchange resin 107MB (provided by Zhejiang Zhengguang Industrial Co., Ltd.).

[0080] The activated carbon adsorption device is equipped with an activated carbon adsorption membrane, the material of which is granular activated carbon, and the pore size of the activated carbon adsorption membrane is 30nm; provided by Shenzhen Membrane Spring Co., Ltd.

[0081] The chemical plating waste liquid is derived from the waste liquid generated during chemical copper plating.

[0082] The second aspect of this embodiment provides a chemical plating wastewater treatment device, the structure of which includes a booster pump, a protective filter, a precision filter, a deactivation storage tank, a high-pressure pump, an ultra-precision filter, a pH adjustment tank, a high-pressure pump, an ion exchange resin, and an activated carbon adsorption device connected in sequence.

[0083] The components of the processing device are tightly connected by pipes; the pipes are made of PVC.

[0084] The aforementioned booster pump is an IHF fluoroplastic chemical booster pump, model IHF80-65-160A, with a power of 1.5KW, provided by Shanghai Maike Pump Industry Manufacturing Co., Ltd.

[0085] The high-pressure pump is a multi-stage centrifugal high-pressure pump with a power of 1.5KW and a model number of BL2-15S; it was provided by Xinji Pump Industry Group Co., Ltd.

[0086] The third aspect of this embodiment provides the application of the processing technology or processing device described above, specifically applied in the electronics and electrical industry, for the collection and treatment of wastewater from PCB (printed circuit board) systems.

[0087] Performance testing methods

[0088] The chemical plating waste liquid 1 to 10 were treated using the chemical plating waste liquid treatment process described in Example 1.

[0089] Specifically:

[0090] Chemical plating waste liquid 1 was provided by Guangdong Shuocheng Technology Co., Ltd., model SCC-A08LP. The composition formula is shown in Table 1, and the test results are shown in Table 2.

[0091] Chemical plating waste liquid 2 was provided by Guangdong Shuocheng Technology Co., Ltd., model SCC-A08SP. The composition formula is shown in Table 3, and the test results are shown in Table 4.

[0092] Chemical plating waste liquid 3 was provided by Anmet Co., Ltd., model number... U Plus, the component formulation is shown in Table 5, and the test results are shown in Table 6.

[0093] Chemical plating waste liquid 4 was provided by Rohm and Haas Electronic Materials CPM Holdings, model Circuposit 880. The composition formula is shown in Table 7, and the test results are shown in Table 8.

[0094] Chemical plating waste liquid 5 was provided by Guangdong Tiancheng Technology Co., Ltd., model SkyCopp 365SP. The composition formula is shown in Table 9, and the test results are shown in Table 10.

[0095] Chemical plating waste liquid 6 was provided by Guangdong Tiancheng Technology Co., Ltd., model SkyCopp 3651. The composition formula is shown in Table 11, and the test results are shown in Table 12.

[0096] The chemical plating waste liquid 7 was provided by Guangdong Tiancheng Technology Co., Ltd., model SkyCopp 3652. The composition formula is shown in Table 13, and the test results are shown in Table 14.

[0097] Chemical plating waste liquid 8 was provided by Yancheng Baikal Electronic Materials Co., Ltd., model LM1000 series. The composition formula is shown in Table 15, and the test results are shown in Table 16.

[0098] Chemical plating waste liquid 9 was provided by Shenzhen Zhengtianwei Technology Co., Ltd., model FEC-3088 series. The composition formula is shown in Table 17, and the test results are shown in Table 18.

[0099] Chemical plating waste liquid 10 was provided by Shenzhen Fulit Technology Co., Ltd., model HDP-380 series. The composition formula is shown in Table 19, and the test results are shown in Table 20.

[0100] The analysis methods for each indicator are as follows.

[0101] 1. Chemical composition analysis was performed on the treated product; the analytical and calculation methods are as follows:

[0102] (1) Copper ion analysis method (additive)

[0103] a) Use a pipette to draw 25.0 mL of the sample to be tested and place it into a 300 mL Erlenmeyer flask.

[0104] b) Add 25 ml of distilled water and 20 ml of 20 wt% H2SO4 aqueous solution, and shake well.

[0105] c) Add 20 mL of (50 g / L KI + 200 g / L KSCN) solution and shake well.

[0106] d) Add 2-3 drops of 1wt% starch solution

[0107] e) Titrate with 0.1N Na2S2O3 solution until the blue color disappears.

[0108] calculate:

[0109] Copper ions (g / L) = 0.1N Na₂S₂O₃ dosage (mL) × 0.254

[0110] Other additives can be calculated using a similar method, i.e., additive (mL / L) = 0.1N Na2S2O3 dosage (mL) × 5.08

[0111] (2) Analysis methods for complexing agents (basic agents)

[0112] A. Potassium sodium tartrate system

[0113] a) Use a pipette to draw 2.0 mL of the sample to be tested and place it into a 250 mL Erlenmeyer flask.

[0114] b) Add 50 ml of distilled water and 5 mL of 20% H2SO4 aqueous solution, and shake well.

[0115] c) Heat and keep boiling for 10 minutes.

[0116] d) Add 100 mL of distilled water and 5 g of MnSO4·H2O

[0117] e) Heat until completely dissolved, add 20 mL of 0.1 N KMnO4 standard solution using a pipette, heat to boiling for 10 min, and then cool to room temperature (25 °C).

[0118] f) Add 2g KI and 2mL 1wt% starch solution

[0119] g) Titrate with 0.1N Na₂S₂O₃ solution until the blue color disappears, and record the volume as V (mL).

[0120] calculate:

[0121]

[0122] Other basic reagents can be calculated using a similar method, i.e.

[0123] Basic reagent mL / L = [0.1N KMnO4 volume (mL) - 0.1N Na2S2O3 volume (mL)] × 6.3B. EDTA system

[0124] a) Pipette 10.0 ml of the sample to be tested into a 250 ml volumetric flask and add 75 ml of distilled water.

[0125] b) Add 20 ml of pH 10.0 buffer and 12 drops of 0.1 wt% PAN indicator (the main component of which is 1-(2-pyridiniazo)-2-naphthol).

[0126] c) Use 0.016M Cu 2+ Titrate the standard solution until it turns violet, and record the volume as V (mL).

[0127] Calculation: Complexed EDTA g / L = 6.55 × copper ion concentration g / L

[0128]

[0129] Total EDTA (g / L) = Complexed EDTA + Free EDTA

[0130] Note: Quantitative calculations were performed using EDTA·4Na·2H2O.

[0131] (3) Analysis methods for sodium hydroxide and formaldehyde (reducing agent)

[0132] a) Pipette 5.0 mL of the sample to be tested into a 250 mL beaker.

[0133] b) Add 100 mL of distilled water

[0134] c) Titrate to pH 10.2 with 0.10N HCl standard solution using a pH meter (pH 10.0 buffer). d) Record the volume V1 used to determine the NaOH concentration.

[0135] e) Titrate with 0.10N HCl standard solution to a pH of 10.0.

[0136] f) Add 25 mL of 1 M sodium sulfite solution

[0137] g) Titrate with 0.10N HCl standard solution to pH 10.0, record the volume V2 used in this step, and use it to calculate the formaldehyde concentration / reducing agent content.

[0138] calculate:

[0139]

[0140] Other basic reagents can be calculated using a similar method, i.e., reducing agent mL / L=V2(mL)×2.00(4) Nickel content analysis method

[0141] Analysis was performed using an atomic emission spectrophotometer. The specific operating procedure was as follows: power on—connection—select nickel lamp—correct / select nickel element gas flow rate and wavelength (flow rate 1700, wavelength 232.0)—peak finding—preheat for 20 minutes—start acetylene gas and ignite—energy adjustment—testing.

[0142] 2. Calculate the throttling rate:

[0143]

[0144] 3. National indicator testing:

[0145] According to the national emission standard GB21900-2008, the specified elements were detected using ICP-MS, specifically using an Agilent 7700 / 7800 (MS) from the United States; the pH of the solution was detected using a pH meter, specifically using a Leici pH meter pHS-3G.

[0146] Note: All reagents used in the above analysis are commercially available. Unless otherwise specified, the solvent for the solutions is water.

[0147] Performance test results

[0148] 1. The component content and throttling rate of electroless plating waste liquid 1, electroless plating waste liquid 2, and electroless plating waste liquid 3 before and after treatment are shown in Table 1-20.

[0149] Table 1

[0150]

[0151] Table 2

[0152] Potassium sodium tartrate 1.32g / L 96.22％ Copper sulfate pentahydrate 0.42g / L 95.80％ formaldehyde 3.12g / L 22.00％ Sodium hydroxide 7.46g / L 25.40％

[0153] Table 3

[0154]

[0155] Table 4

[0156]

[0157]

[0158] Table 5

[0159]

[0160] Table 6

[0161] Basic agent P 2.50 mL / L 97.05％ Copper sulfate pentahydrate 0.12g / L 98.80％ Sodium hydroxide 8.24g / L 17.6％ formaldehyde 3.43g / L 23.77％

[0162] Table 7

[0163]

[0164] Table 8

[0165] EDTA·4Na·2H2O 0.75g / L 97.87％ copper ions 0.10g / L 95.45％ formaldehyde 1.88g / L 24.80％ Sodium hydroxide 10.34g / L 20.46％

[0166] Table 9

[0167]

[0168]

[0169] Table 10

[0170] Potassium sodium tartrate 2.88g / L 91.77％ Copper sulfate pentahydrate 0.15g / L 98.50％ Nickel ions 0.037g / L 91.19％ formaldehyde 3.87g / L 14.00％ Sodium hydroxide 8.67g / L 13.30％

[0171] Table 11

[0172]

[0173]

[0174] Table 12

[0175] Potassium sodium tartrate 2.08g / L 94.80％ Copper sulfate pentahydrate 0.21g / L 97.90％ formaldehyde 3.76g / L 16.40％ Sodium hydroxide 8.56g / L 14.40％

[0176] Table 13

[0177]

[0178] Table 14

[0179] Potassium sodium tartrate 1.53g / L 96.17％ Copper sulfate pentahydrate 0.82g / L 91.80％ Nickel ions 0.085g / L 91.50％ formaldehyde 3.88g / L 13.77％ Sodium hydroxide 8.26g / L 17.40％

[0180] Table 15

[0181]

[0182] Table 16

[0183]

[0184]

[0185] Table 17

[0186]

[0187] Table 18

[0188] FEC-3088M - Basic Agent 3.47 mL / L 95.91％ copper ions 0.15g / L 93.18％ NaOH 7.85g / L 21.50％ formaldehyde 6.08g / L 18.93％

[0189] Table 19

[0190]

[0191] Table 20

[0192] FEC-3088M - Basic Agent 6.43 mL / L 93.57％ copper ions 0.18g / L 91.81％ NaOH 7.81g / L 21.90％ formaldehyde 5.96g / L 14.80％

[0193] 2. The test results of various indicators in the waste liquid discharged after the entire waste liquid treatment process are shown in Table 21 below.

[0194] Table 21

[0195]

[0196]

[0197] Continued table

[0198]

[0199]

[0200] As can be seen from the results in Table 1-21, the chemical plating wastewater treatment process / apparatus provided in this embodiment of the invention can significantly improve the purification effect of chemical plating wastewater. After treatment by the chemical plating wastewater treatment process / apparatus, the content of complexing agents and heavy metals (such as copper ions) in the wastewater is greatly reduced, and it can be recycled and reused, greatly reducing resource waste. The treatment process of this invention is relatively simple, and all indicators of the treated chemical plating wastewater can meet national emission standards, making it safe and environmentally friendly. At the same time, the treatment and reuse process of this invention can be applied to various commercially available chemical plating wastewaters, achieving excellent purification effects and demonstrating strong technical versatility.

[0201] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A process for treating chemical plating wastewater, characterized in that, The treatment steps include: passing the chemical plating waste liquid to be treated sequentially through a protective filter and a precision filter for filtration, then passing it through a deactivation storage tank to reduce the activity of the chemical plating waste liquid, and then sequentially passing it through an ultra-precision filter, a pH adjustment tank, an ion exchange resin, and an activated carbon adsorption device for treatment, collecting the discharged products to obtain the final product. The protective filter is provided with a first filter membrane; the pore size of the first filter membrane is 1-100μm; The precision filter is equipped with a second filter membrane; The filter material of the second filter membrane is at least one of polypropylene, polytetrafluoroethylene, cellulose acetate, ceramic, and activated carbon; the pore size of the second filter membrane is 1-500 nm. The ultra-precision filter is equipped with a third filter membrane; the pore size of the third filter membrane is 0.1-50nm; The processing steps of the deactivation storage tank include: the filtrate after being treated by the protective filter and the precision filter is introduced into the deactivation storage tank, which is connected to an air pump to reduce the activity of the chemical plating solution. The deactivation storage tank has a built-in cooling and temperature reduction device.

2. The chemical plating wastewater treatment process according to claim 1, characterized in that, The filter material of the first filter membrane is at least one of cotton core, polypropylene, polytetrafluoroethylene, cellulose acetate, ceramic, activated carbon, polyethersulfone, mixed fiber resin, polyamide, and polyvinylidene fluoride.

3. The chemical plating wastewater treatment process according to claim 1, characterized in that, The third filter membrane is made of composite nanofiltration membrane or reverse osmosis membrane.

4. The chemical plating wastewater treatment process according to claim 1, characterized in that, After the chemical plating waste liquid enters the pH adjustment tank, the pH of the chemical plating waste liquid is adjusted to 7-8.

5. The chemical plating wastewater treatment process according to claim 1, characterized in that, The ion exchange resin is selected from one or more of the following: strong acid cation exchange resin, weak acid cation exchange resin, chelating resin, redox resin, and metal ion exchange resin.

6. The chemical plating wastewater treatment process according to claim 1, characterized in that, The activated carbon adsorption device is equipped with an activated carbon adsorption membrane with a pore size of 1-100 nm.

7. The chemical plating wastewater treatment process according to any one of claims 1-6, characterized in that, The chemical plating waste liquid comes from the waste liquid generated by chemical copper plating, chemical nickel plating, chemical gold plating, chemical tin plating, chemical cobalt plating, chemical silver plating, chemical palladium plating, chemical iron plating, chemical zinc plating, chemical plating, chemical plating, chemical lead plating, chemical aluminum plating, chemical scandium plating, chemical titanium plating, chemical rhodium plating, and various metal alloys.

8. A chemical plating wastewater treatment device, characterized in that, The structure includes a protective filter, a precision filter, a deactivation storage tank, an ultra-precision filter, a pH adjustment tank, an ion exchange resin, and an activated carbon adsorption device connected in sequence.

9. An application of the processing technology according to claim 1 or the processing apparatus according to claim 8, characterized in that, It is applied in the fields of electronics and electrical industry, automotive industry, aerospace industry, medical device industry, powder metallurgy industry, and machinery manufacturing industry.

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