ADSORPTION OF ISOPROTURON ON HOMOIONIC CLAYS

The adsorption of isoproturon [3-(4-isopropylphenyl)-1,1 dimethylurea) ] on a montmorillonite and on a kaolinite was studied by batch experim ents and Fourier transform infrared spectroscopy (FT-IR). The clays we re saturated with cations such as Al3+, Ca2+, Cu2+, Na+ and hexadecylt rimethylammonium (HDTMA). The studied clays did not show detectable ca talytic activity on abiotic degradation of isoproturon, as evidenced b y HPLC analysis. Adsorption was found related to clay specific externa l surface for HDTMA-saturated clays, while it seems independent from c lay kind and inorganic cation. For clays saturated with inorganic cati ons, no penetration into the montmorillonite interlayer was found and FT-IR spectroscopy showed the involvement of C=O soup of isoproturon i n adsorption. (C) 1997 Elsevier Science Ltd.