A new method for destroying organic contaminants and recycling waste water from printed circuit board manufacturing process effluent streams

Ethylenediaminetetraacetic acid and other organic chelates are widely employed in electroless plating processes used by the printed circuit board and metal finishing industries. These chelating agents can pose problems with downstream waste water treatment, and metals and water recycling processes, due to their ability to complex heavy metal ions and their low biodegradabilities. Conventional treatment methods, such as carbon adsorption, air stripping and reverse osmosis can create secondary waste problems and are normally applied as “end of pipe” treatments. The development of new technology to address these problems would be welcomed. The ROCWAT project, funded by the EC under the “CRAFT” programme, detailed in this paper was undertaken to develop and deliver innovative techniques for the in situ destruction of chelates and other organics found in manufacturing process chemistries and effluent streams.