Colouring of alumina is a standard process in anodizing. Focus of applications turns more and more to coloured facings of buildings in fairy looks. Under environmentals aspects these dyes are a problem, because always more stabile and resistent structures and formulas are developed.

In this point the Enviolet UV-Oxidation is a perfect solution. In shortest time and with low energy demand the chromophoric structures are destroyd and the dyes are eliminated from rinsing and/or waste water. Nearly all cases show the possibility to recover the leached water for the rinsing process. The profitability of the production process will be improved significantly.