Method for recycling copper from basic waste etching liquid

Abstract

The invention provides a method for recycling copper from a basic waste etching liquid. The method is characterized by comprising the following steps of: (1) extracting copper by adopting an organic phase of Lix<R> series extractant:N235 extractant: kerosene or 200#solvent oil and a basic waste etching liquid; (2) washing the loaded organic phase obtained in the step (1) by using a diluted sulfuric acid solution; (3) performing back-extracting on the loaded organic phase washed in the step (2) and a copper sulfate solution, and returning the back-extracted organic phase to the step (1) for recycling, wherein the water phase is a copper sulfate solution; and (4) electrically depositing the copper sulfate solution in the step (3) by adopting a metal cathode to obtain acid copper, and returning the copper sulfate solution after the step of electrically deposited the copper to the step (3) for recycling. The method for recycling copper from an acid waste etching liquid can be used for selectively separating copper from a basic waste etching liquid, and is simple in process and good in separation effect.

Description

technical field [0001] The invention relates to a method for recovering copper from alkaline waste etching solution. Background technique [0002] The production process of printed circuit board (PCB) is long, and the etching process is the largest part of the PCB production process. In the etching process, when the etching index, including speed, side erosion coefficient, surface cleanliness, etc., is lower than the process requirements due to too many substances dissolved in the etching solution, it becomes a waste etching solution. Etching liquids include acidic etching liquids, alkaline etching liquids and micro etching liquids. Alkaline etching generally speaking, every 1m produced 2 The circuit board needs to consume 2~2.5L of etching solution, and correspondingly produce 2~2.5L of waste etching solution. The concentration of copper ions is very high, reaching 160g / L or higher. The main components of these waste etching solutions are: heavy metal copper , ammonium s...

AI Technical Summary

Problems solved by technology

The grade of sponge copper obtained by the replacement method is not high, and the copper content in the tail liquid after copper recovery is high. Although the copper powder produced by the electrolysis method has high purity and is better than the copper powder produced by other methods, the efficiency of the copper powder produced by the electrolysis method is higher than that of copper powder produced by other methods. Relatively low, high power consumption, and the concentration of heavy metal ions in the waste liquid cannot be reduced very low, strict treatment must be carried out before discharge, and the electrolysis method is easy to produce chlorine gas; neutralization precipitation method to treat copper-containing waste liquid, the process Simple, low investment, but the copper content of the mother liquor after copper sulfate crystallization is high, which needs further treatment, and the inorganic and organic substances such as ammonium salt in the wastewater cannot be recycled, causing serious environmental pollution

Although the extraction method currently used in the industry can extract copper, the copper extraction rate is low, only about 50%; the copper content in the wastewater is still about 60g / L, and the etching speed is slow when returning to etching.