The photodegradation of aminopolycarboxylic acid (NTA, IDA) and aminopolyphosphonic acid (EDTMP) induced by complexation with iron(III) or copper(III) is described. The phenomenon generally observed is a photoredox process giving rise to the reduced metal and oxidized ligand. The quantum yields of the reaction can vary from 10-6 to 0.5 according to the ligand, the metal, the pH and the excitation wavelength. Apart from EDTMP-Cu complex, the complexation of these non absorbing compounds by iron(III) and copper(III) makes their photodegradation possible with solar light. The half lives of the pollutants when involved in such a process in the environment are estimated.
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