Regeneration method of acidic etching solution

Abstract

The invention discloses a regeneration method of an acidic etching solution. The regeneration method comprises the steps that oxidation is carried out, specifically, oxidant is added into the acidic etching solution, cuprous ions in the acidic etching solution are converted into copper ions, and ORP value is controlled; decompressing and evaporating are carried out, specifically, decompressing andevaporating are carried out on the oxidized acidic etching solution; continuing evaporation of residual temperature is carried out, specifically, when waste water forms crystals, heating is stopped,the residual temperature is enabled to be continue evaporated, and the atmospheric pressure state is returned to after the temperature is reduced to normal temperature; then, the saturated acidic etching solution on the upper part of the crystals is extracted into a freezing tank to reduce the temperature to 5-10 DEG C, and then copper chloride crystals are taken out, wherein the residual solutionis saturated copper chloride solution; and a new acidic etching solution is made, specifically, evaporated water and a proper amount of diluent are added into the saturated copper chloride solution to obtain the new acidic etching solution. The use of decompressing and evaporation can avoid the destruction of the original components of the acidic etching solution, byproducts of the copper chloride crystals are obtained, and the regeneration of the acidic etching solution is realized.

Description

technical field [0001] The invention relates to a recycling technology for etching waste liquid, in particular to a regeneration method for acidic etching waste liquid. Background technique [0002] In the past 20 years, China's PCB industry has maintained an average annual growth rate of 10%. At present, there are more than 3,500 PCB companies of various sizes, with a monthly output of 120 million square meters. Etching is a process that consumes a large amount of chemicals and water in PCB production, and it is also the process that produces the largest amount of waste liquid and wastewater. Generally speaking, about 2-3 liters of etching solution is consumed for each square meter of double-sided panels with a normal thickness (18 μm), and Generate 2-3 liters of waste etching solution. my country's PCB industry consumes more than 60,000 tons of refined copper per month, and the total amount of copper in the copper etching waste liquid produced is more than 50,000 tons / mon...

AI Technical Summary

Problems solved by technology

The principle of this method is simple, but the evaporation temperature is high, the original components of the acid etching solution are easily destroyed, and the energy consumption demand is very large during evaporation, and the economic benefit is low