Acidic etching solution recovery method

Abstract

The invention discloses an acidic etching solution recovery method. The acidic etching solution recovery method comprises the following steps that an acidic etching waste solution is pretreated, and the pH value of the acidic etching waste solution is regulated to be in an alkaline range; the acidic etching waste solution is extracted by using a solvent to obtain a loaded copper oil phase and a first water phase; secondary extraction is carried out on the loaded copper oil phase to obtain a second oil phase and a second water phase; a copper extraction agent is added into the second oil phaseto obtain a loaded copper extraction solution; the second water phase is electrolyzed, copper ions in the second water phase are deposited, and electrodeposited liquid and deposited copper are obtained; and the pH value of the first water phase is adjusted to be neutral, and then an alkaline solution is formed by adopting a membrane treatment fine adjustment or reduced pressure distillation process. The acidic etching solution recovery method has the advantages that the technological process and the management program of a printed circuit board factory are not changed, only the waste solutionneeds to be discharged into an acidic etching solution treatment and recovery system, the whole process is continuously and automatically performed, the technological content of equipment is high, andcondensation utilization and zero emission are achieved.

Description

technical field [0001] The invention relates to the technical field of regeneration and recovery of etching solution, in particular to a method for recovery of acidic etching solution. Background technique [0002] In 2008, the output value of my country's PCB circuit boards reached 118.3 billion, accounting for 32% of the world's output value, and the PCB output reached 150 million square meters, ranking first in the world. Chinese PCB companies have grown rapidly and gradually formed a development trend of scale and industrialization. However, the increase in output value also brings environmental pollution, especially in the PCB circuit board etching process, which consumes a lot of chemical reagents and produces a lot of waste liquid and waste water. Half of the PCB manufacturers use acid etching solution in the etching process, and most of the PCB Environmental protection companies mix it with alkaline etching solution to precipitate copper, and after separation, produc...

AI Technical Summary

Problems solved by technology

[0003] At present, there are many units at home and abroad that research and develop metal copper recovery from waste acid etching solution, including many scientific research institutes and colleges and universities. The problem of environmental pollution is serious, and it has no practical value for promotion from the perspective of economic benefits of condensation utilization of enterprises, energy saving, emission reduction and environmental protection.

[0004] 1. Compared with the direct electrolysis method, the conventional electrolysis method avoids Cu in the cathode area + Migrate to the anode region and re-oxidize to Cu 2+ , adopts the configuration of small cathode and large anode, but it is not very convenient in operation, a large amount of chlorine gas is generated during the electrolysis process, the production safety risk of the collection device is high, the peripheral equipment is corroded, the labor intensity of employees is high, and the cost of electricity is high

[0005] 2. Compared with the method of using ionic membrane electrolysis to regenerate and recycle copper etching waste liquid, due to the high requirements of the ionic membrane on the use environment, it will deteriorate with the progress of the process, resulting in unstable membrane performance, and the ionic membrane is expensive

In addition, the current efficiency is only 84.3%, and the possibility of chlorine and hydrogen evolution is relatively high

[0006] 3. Compared with the diaphragm electrolysis method, the equipment manufacturing is complicated, and cuprous ions are easily oxidized. The electrolysis system must seal the electrolytic cell with nitrogen gas, and the electrolytic cell cannot be checked in time, and the operation is very inconvenient