|Cox, L - CSIC-IRNAS SEVILLA SPAIN|
|Hermosin, M - SCIC-IRNAS SEVILLA SPAIN|
|Cornejo, J - CSIC-IRNAS SEVILLA SPAIN|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: September 27, 2001
Publication Date: N/A
Technical Abstract: Sorption of imidacloprid on organic saturated octadecylammonium, C18, and dioctadecyldimethylammonium, DOD, and inorganic (Fe) saturated montmorillonites which have high (SAz) and low (SWy) layer charge, has been investigated. Sorption isotherms were fitted to Freundlich equation. Imidacloprid-montmorillonite complexes were studied by X-Ray diffraction and FT-IR techniques. Imidacloprid sorption coefficients, Kf, decreased i the order C18SWy> C18SAz>FeSWy>DODSWy>=DODSAz. The low layer charge and saturation by primary alkylammonium cation facilitates sorption of imidacloprid in the interlayer of the smectite, which is corroborated by the increase in basal spacing observed in X-ray diffractograms and by the presence of shifted adsorption bands in FT-IR spectra. Imidacloprid sorbs in the interlayer space of smectite mainly by weak hydrophobic interactions and, in the case of primary alkylammonium saturated by polar bond between the NO2 group and NH of the alkylcation.