ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Magadiite as a support for the controlled release of herbicides

Alécio R. Nunes, Kelly R. O. Araújo, Aline O. Moura, and Alexandre G. S. Prado

Ciência e Tecnologia Goiano (IF Goiano), Iporá, Brazil

E-mail: aleciornunes@gmail.com

Abstract: Diuron and 2,4-dichlorophenoxyacetic acid were intercalated into layered silicate magadiite and the presence of anchored herbicides within the lamellas was confirmed by Fourier transform infrared spectroscopy. X-ray diffraction patterns and surface area analysis showed that the intercalation of herbicides decreased basal lamellar spacing and the surface area of the silicate. According to the results obtained from surface charge analysis, the main interactions between magadiite and the herbicides were mediated by hydrogen bond formation. Controlled release studies demonstrated that the delivery of the herbicides occurred substantially faster at pH 9, while the difference in delivery rates at pH 1 and pH 4.6 (the point of zero charge) was far less marked, although release at the more acidic pH was slightly quicker. The use of magadiite as a herbicide support shows great potential for the development of controlled release systems and will contribute to more sustainable forms of weed control.

Keywords: Silica ; Mesoporous ; Hybrid ; Herbicides 

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-017-0300-y

Chemical Papers 72 (2) 479–486 (2018)