Some experimental methods for the treatment of ammonia etching wastewater are introduced.

A reagent for removing lead of alkaline waste etching liquid and its removing lead rate equation by quadratic orthogonal designing;

Recovery of copper from spent etching solution by Lix54-100 extractant;

The earliest domestic originated zero emission clean production process for mass centralized resource utilization of circuit board spent etching solution developed by Nanxi Chemical Plant,Baiyun District of Guangzhou was studied and three key technical conditions were optimized by orthogonal experiment including weight of mixed quicklime of 0.

Factors that may influence copper recovery rate including pH, temperature and cuprous ion concentration were studied when using neutralization process to recover copper from spent etching solution, and options to choose the best conditions for precipitating copper were optimized.

Research Status and Prospects for spent etching solution

There are two different typical treatment technologies in PCB spent etching solution in China now-cyclic regeneration end producing copper sulfate,In the paper,the technology process,resource utilization and environment infection are compared and analyzed between them.