Photodegradation of ethylenediaminetetraacetic acid (EDTA) and ethylenediamine disuccinic acid (EDDS) within natural UV radiation range

The rate of photodegradation of two chelating agents, ethylenediaminetetraacetic acid (EDTA) and an isomeric mixture of ethylenediamine disuccinic acid (EDDS), was analysed in humic lake water and in distilled water using exposure to sunlight, and in the laboratory using lamps emitting UV radiation in the range 315–400 nm. Degradation was studied using Fe(III) complexes and sodium salts of chelates. Fe(III) complexes were illuminated at pH 3.1 and 6.5.