Copper recovery system for acidic etching waste liquid of printed board and method for regeneration of etching liquid

Abstract

The invention relates to the field of recovery, in particular to a copper recovery system of printed board acid etching waste solution and an etching solution regeneration method. The system comprises a set of solid-liquid separation device, a current control device and an electrolytic bath, wherein the electrolytic bath is divided into a cathode chamber and an anode chamber by an ion membrane; the insides of the cathode chamber and the anode chamber are respectively provided with a cathode plate and an anode plate; the cathode plate and the anode plate are respectively connected with the current control device; all the bathes are connected with the electrolytic bath by pipelines to form a closed loop, through arranging the ion membrane in the electrolytic bath to divide the electrolytic bath into the cathode chamber and the anode chamber, when waste solution enters the electrolytic bath, the liquid in each chamber has electrolysis reaction under the action of respective polar plate to precipitate copper in the cathode chamber, the copper is recovered by a filter unit, and the bath solution enters a mixing bath for regeneration and reuse. The system reaches the goal of the regeneration of etching solution and recovery of copper.

Description

technical field [0001] The invention relates to the field of recycling of raw materials, in particular to a copper recovery system for acidic etching waste liquid of printed boards and a method for regenerating the etching liquid. Background technique [0002] With the annual growth rate of my country's electronics industry exceeding 20%, it has driven the development of printed circuit board (PCB) and related industries. An important step, in the production process of printed circuit boards, acid and alkaline etching processes are usually used to produce circuit boards, and these enterprises produce a large amount of corrosion waste liquid every year. [0003] Among them, the acidic etching liquid includes hydrochloric acid, hydrochloric acid + sodium chlorate, hydrochloric acid + hydrogen peroxide and other processes, and the main component of the acidic etching waste liquid is CuCl 2 , HCl, NH 4 Cl or NaCl, etc., wherein the copper content is 100-145g / L, the acidity is 1...

AI Technical Summary

Problems solved by technology

Etching solution can not be regenerated, resulting in waste

[0006] 2. Dilute neutralization extraction method: This method is to put a large amount of NaOH or ammonia water into the acid etching solution including hydrochloric acid, hydrochloric acid + sodium chlorate, hydrochloric acid + hydrogen peroxide and other process etching waste liquid, and neutralize to pH = 2-3. Extracting copper also contains a large amount of chlorine, although this method does not produce chlorine, it will produce a large amount of waste water, the basic investment of equipment is large, and the consumption of ammonia water is large

[0007] 3. Diaphragm electrolysis method: This method uses active Cl - The anode performs diaphragm electrolysis on the acidic etching waste liquid, and the metal copper recovered by electrolysis is in the form of powder, but a large amount of hydrogen and chlorine gas are generated when the hydrochloric acid solution is electrolyzed, which is extremely dangerous, and the anode is consumed very quickly, and the production and operation costs are extremely high

[0008] 4. Sulfuric acid extraction distillation method: This method is to add sulfuric acid to the acidic etching waste liquid for high-temperature distillation, use the different boiling points of sulfuric acid and hydrochloric acid to distill, separate and recover HCl and produce copper sulfate. This method needs to add a large amount of sulfuric acid to replace CuCl with copper sulfate. , since copper sulfate is a chemical product, special chemical production qualifications are required, and circuit board manufacturers do not have production qualifications

[0009] There are various disadvantages in the above four methods of recovering copper from waste acid etching solution, and they should not be used in production.

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