Zero discharge alkaline copper etching waste liquid recycling technology method

Abstract

The invention discloses a zero discharge alkaline copper etching waste liquid recycling technology method. The zero discharge alkaline copper etching waste liquid recycling technology method includesfollowing steps: adding hydrochloric acid in copper etching waste liquid flowing from an etching machine, wherein the hydrochloric acid performs complexation breaking and precipitation on copper ammonia complex ions in the copper etching waste liquid; feeding the copper etching waste liquid obtained after the complexation breaking and precipitation into a solid-liquid separation device, and separating out clear liquid and copper sludge through the solid-liquid separation device; adding an ammonia adjuvant in the clear liquid, forming an alkaline etchant by adding the ammonia adjuvant in the clear liquid, and adding the alkaline etchant in the etching machine; adding concentrated sulfuric acid in the copper sludge after being pulped for dissolving the pulped copper sludge, preparing a copper sulfate mixed solution, and obtaining industrial grade copper sulfate after performing re-cooling crystallization and dehydration separation on the copper sulfate mixed solution. The zero dischargealkaline copper etching waste liquid recycling technology method really achieves zero discharge, thoroughly solves an environment pollution problem caused by the copper etching waste liquid, is simple, high in treating efficiency, low in energy consumption, and small in demand quantity of devices, and greatly reduces recycling cost.

Description

technical field [0001] The invention relates to the technical field of copper etching waste liquid recovery, in particular to a zero-discharge alkaline copper etching waste liquid recovery process method. Background technique [0002] Alkaline etching solution is generally produced by professional electronic chemical factories. Fresh alkaline etching solution, also known as sub-liquid, is mainly composed of ammonium chloride [NH 4 Cl] and ammonia [NH 3 ·H 2 O]. The alkaline etching solution is added to the etching machine and the copper etching solution [CuCl 2 ] reaction to form a cupramine complex ion [Cu(NH 3 ) 4 ] 2+ , [Cu(NH 3 ) 4 ] 2+ It has strong oxidizing property and can undergo redox reaction with copper foil to dissolve copper foil. During the redox reaction, the Cu in the copper etching solution 2+ The ion concentration will get higher and higher as the Cu 2+ When the ion concentration is close to saturation, the etching speed will become slower, and...

AI Technical Summary

Problems solved by technology

[0009] The main purpose of the present invention is to provide a zero-emission recovery process for alkaline copper etching waste liquid, which aims to solve the problems of large environmental pollution, long recovery process, large equipment investment, and high cost of copper extraction in the existing recovery process.

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