Background The EU metal plating industry discards about 420 million litres of contaminated passivating bath liquid every year, resulting in the production of 40,000 tonnes of toxic metal sludge waste. Current technology carries a major environmental problem: the estimated replacement chemical costs are €168 million and the treatment and disposal costs are €76 million per year. The metal plating industry consists of around 10,000 companies, mainly SMEs, across Europe. In May 2002, the European Committee for Surface Treatment (CETS) reported that there are currently no available technologies to extend the lifetime of the passivating baths. CETS is producing an inventory of best available technologies in compliance with the Integrated Pollution Prevention and Control Directive. Extending the lifetime of the passivating baths would avoid the negative environmental effects and economic losses. Research has shown that the selective removal of tramp ions (Fe3+ and Zn2+) from the baths, in order to maintain a constant quality of the baths, would provide a solution. Such selected removal of tramp ions can be accomplished by the innovative emulsion pertraction (EP) technology. Tests at pilot scale have shown that using EP technology reduces the environmental effects and costs by 90%. Objectives The project aimed to apply EP technology for the first time on a full scale and to demonstrate the its feasibility. Other objectives included: • Extending the lifetime of the black and blue passivating baths from 0.3 - 2 months to 1.5 - 2 years; • Demonstrating the reliability, sustainability, environmental and economic benefits of the technology over a 15-month period; • Integrating the innovative technology within the entire production process of the participating metal platers; and • Showing the improved quality of the plated products when using EP technology. Results The project demonstrated that EP technology can be used to remove tramp ions from passivating baths in the metal plating industry. As a result, the lifespan of the baths is increased substantially: the blue passivating bath at one of the participating metal platers has an extend lifespan of 2 years instead of 6 weeks. For the black passivating bath, the lifespan was extended from one to three years. As a consequence, considerable savings in chemicals, energy and water have been achieved, resulting in a payback time of the installation of about one year. The project is relevant for several EU policies. The demonstrated technology may qualify as a BAT. A further impact may be the replacement of Cr6+ passivating (which is more harmful) by Cr3+ passivating with emulsion pertraction. Several directives (end of life vehicle, the restriction of the use of hazardous substances in electrical and electronic equipment, and waste electrical and electronic equipment directives) limit or prohibit the use of CrVI based chemicals. The quality that can be obtained with Cr3+ passivating in combination with emulsion pertraction is better than traditional Cr6+ passivating, and for this reason, the technology may contribute to the accelerated phasing out of this process. This project has been awarded the title of "Best of the Best" from a shortlist of 22 "Best" LIFE Environment projects in 2006-2007