CN-115724547-B - Comprehensive utilization method of circuit board brown chemical waste liquid

Abstract

The invention discloses a comprehensive utilization method of circuit board brown chemical waste liquid, which belongs to the technical field of brown chemical waste liquid treatment methods, and comprises four steps of pretreatment, deep purification of brown chemical waste liquid at room temperature, recovery of cathode copper by electrolytic deposition and recovery of ink residue by synergistic acidification of ink waste liquid; according to the method, high-quality cathode copper plates are electrolytically recovered under the conditions of no need of heating and no use of strong oxidants such as potassium permanganate and sodium chlorate, the risks of environmental pollution and fire hazard and chlorine leakage caused by copper recovery through electrolytic deposition in the traditional secondary treatment process of the brown oxidation waste liquid are avoided, meanwhile, the ink waste liquid is cooperatively treated, a large amount of consumption of sulfuric acid and liquid alkali is saved, carbon emission is reduced, and good economic and environmental benefits are realized.

Inventors

• GAO DONGRUI
• HUANG JIANBO
• ZHANG JUNQING

Assignees

• 广东臻鼎环境科技有限公司

Dates

Publication Date

20260508

Application Date

20221118

Claims (5)

1. 1. The method for comprehensively utilizing the circuit board browning waste liquid is characterized by comprising the following steps of: Step one, the complex breaking treatment of the brown oxidation waste liquid at room temperature, namely adding 5-10 kg/(1000L of brown oxidation waste liquid) of a composite catalyst into the brown oxidation waste liquid at room temperature, and stirring and reacting for 2-5 hours to obtain a first brown oxidation waste liquid; step two, deeply purifying the first brown oxidation waste liquid, namely slowly adding 2-5 kg/(1000L brown oxidation waste liquid) of deep purifying agent into the first brown oxidation waste liquid obtained in the step one to reduce the content of organic pollutants, and filtering and discarding the supernatant to obtain a second brown oxidation waste liquid; Step three, electrolyzing the second brown oxidation waste liquid to recover cathode copper, namely transferring the second brown oxidation waste liquid obtained in the step two into an electrolytic tank, adding 0.1-0.5 kg/(1000L brown oxidation waste liquid) of an electrolytic additive, regulating current density according to the change of copper ion concentration, electrolyzing to recover cathode copper, and discharging the electrolyte to obtain copper-depleted brown oxidation waste liquid when the copper ion concentration in the electrolyte is reduced to below 2 g/L; step four, cooperatively treating the ink waste liquid, namely adding the copper-depleted brown oxidation waste liquid obtained in the step three into the ink waste liquid, stirring to obtain a mixed liquid, controlling the adding amount of the ink waste liquid to enable the pH value of the mixed liquid to be 2-3, and then carrying out solid-liquid separation by using a centrifuge to obtain ink residues and comprehensive waste water; the composite catalyst comprises 50-70 parts by weight of manganese dioxide, 10-30 parts by weight of ferric oxide and 10-30 parts by weight of aluminum oxide; And the deep purifying agent in the second step is barium chloride.
2. 2. The method for comprehensively utilizing the circuit board browning waste liquor according to claim 1, wherein the electrolytic additive in the third step is a mixture of epichlorohydrin dimethyl polymer and polymeric quaternary ammonium salt.
3. 3. The method for comprehensively utilizing the circuit board browning waste liquor according to claim 2, wherein the addition amount of the epichlorohydrin dimethyl polymer and the polymeric quaternary ammonium salt is 0.1% -0.5% of the weight of the browning waste liquor.
4. 4. The method for comprehensively utilizing the circuit board browning waste liquor according to claim 3, wherein the weight ratio of the epichlorohydrin dimethyl polymer to the polymeric quaternary ammonium salt is (1.5-3.5): 1.
5. 5. The method for comprehensively utilizing the circuit board browning waste liquor according to claim 1, wherein the current density in the third step is 50-200A/m 2 .

Description

Comprehensive utilization method of circuit board brown chemical waste liquid Technical Field The invention relates to the technical field of a brown oxidation waste liquid treatment method, in particular to a method for comprehensively utilizing a circuit board brown oxidation waste liquid. Background In the life of people, all automatic control products, such as spacecraft, high-speed rail of airplane, automobile and steamship, small-sized computer, mobile phone and even pedometer carried by many people, can be automatically controlled by transmitting the products through a circuit board (PCB). The PCB (printed circuit board) is a support body of electronic product components, is a hardware carrier which is the most basic of the information society at present, and the PCB (printed circuit board) industry is the pillar industry of the China electronic information industry, and the growth rate of the PCB (printed circuit board) is increased in the same rate as the electronic information industry. In particular, when the 5G age is started, everything is interconnected, new energy automobiles and intelligent household appliances put forward higher requirements on circuit board manufacturing technologies, for example, the requirements on multilayer line precise circuit boards are more and more, the lamination process in the multilayer circuit board manufacturing is an indispensable link, the surface browning treatment before lamination is an indispensable process, and the purpose of the surface browning treatment is to form a surface passivation blocking layer so that the surface of metal copper can not react with resin to generate water vapor during lamination, or attack the copper surface so that interlayer bonding force is insufficient to cause interlayer stripping, and the contact surface area between the metal copper and the resin is increased in the oxidation process, so that good bonding force is obtained after lamination. The common browning process comprises the following treatment processes: the process of acid washing, degreasing, activating and browning is that the browning treatment is a chemical copper etching reaction process, with the progress of the browning production, the concentration of copper ions in the browning liquid is continuously increased, when the copper ions come over a certain limit (generally 25-35 g/L), the browning liquid can generate the quality problems of white brown copper surface, uneven brown copper surface color and the like due to excessive copper ions, at the moment, the browning tank must be supplemented with new browning liquid to enable the copper ion concentration to be lower than 35g/L, the new liquid is supplemented, and waste liquid is discharged from the browning tank to form brown waste liquid, in addition, the browning tank also needs to be periodically replaced by thoroughly cleaning the tank liquid to form a large amount of brown waste liquid, according to industrial technical data, 4-5t brown waste liquid is discharged every 1 ten thousand square meter circuit board is manufactured, the annual output of Chinese circuit board is more than 10 hundred million square meters, according to the method, more than 50 ten thousand tons of brown waste liquid is generated in the industry of circuit boards in year, the brown waste liquid contains a large amount of sulfuric acid, hydrogen peroxide, alcohol amine, alcohol ether, thiazole and benzene ring organic matters, belongs to dangerous waste, if the disposal is improper, the pollution to the environment is very serious, the main treatment mode at present is that circuit board manufacturers transport the brown waste liquid to enterprises with hazardous waste disposal qualification for treatment, hazardous waste disposal units treat the collected brown waste liquid by a Fenton method advanced oxidation method to generate a large amount of copper and iron sludge, resources are wasted, the energy consumption is high, meanwhile, the solid waste obtained by the brown waste liquid disposal has the risk of secondary pollution environment, in addition, a small part of circuit board enterprises treat the copper by a method of electrolytic deposition after macromolecule organic matters are broken by sodium hypochlorite oxidation, but the recovered metal copper is a copper powder and medicine water mixture, the selling price is low, and the risk of short circuit and fire in the process of electrowinning copper from the brown chemical waste liquid exists (the circuit board industry has a plurality of cases of fire caused by electrowinning waste liquid). The waste ink liquid produced in the circuit board production process mainly refers to the waste liquid in the developing and demoulding processes, and contains a large amount of photosensitive films, welding-resistant film residues and the like, wherein the waste liquid is alkaline, the pH value is generally 11-13, the content of organic pollutants is very high, and the range