Around 1.7 million tons electronic scrap must be recycled every year in Germany. This can release toxic halogens or oxo-halogen compounds (for example high toxic and carcinogen bromate) because of halogenated flame retardant.
While treating metal oxide residual products from recycling of electronic scrap the Duisburg experts did challenge themselves to convert the bromine impurities into a safe and uncritical substance.
The Grillo-Bromine-Reduction jointly developed by R&D and production makes use of the strong reducing agent sodium hydrogen sulfite. This at first glance simple method is actually a new way to avoid the formation of toxic bromate. The dangerous bromine vapors become directly an easily, safe and environmentally friendly transportable bromide product, which can further industrially be used.
The process enlarges the circular economy of waste of electrical and electronic equipment (WEEE) to the element bromine. The valuable but hard to handle bromine can be recovered and be used, e.g. as raw material for flame retardant. “We are proud that we managed to develop a highly efficient process on industrial scale and that the resulting products are completely bromine free” said Dr. Oliver Groß. Dr. Céline Réthoré, responsible for the development of this process, added “the main advantage is that this process is industrially scalable, can be easily adapted to individual processes – and can also be transferred to other processes where iodine, bromine or chlorine is involved.”
The process has already been applied in exhaust air scrubber from laboratories. The process is also applicable in the pharmaceutical, agrochemical and galvanic industries: everywhere where halogen containing – in particular iodine and bromine containing- material streams have to be treated. Grillo is looking for partners in others application areas to allow an ecologically ideal treatment of halogen compounds.