Table of Contents
International Journal of Inorganic Chemistry
Volume 2011, Article ID 243519, 6 pages
http://dx.doi.org/10.1155/2011/243519
Research Article

Kinetics of Reduction of Colloidal MnO2 by Glyphosate in Aqueous and Micellar Media

1Department of Applied Chemistry, Zakir Hussain College of Engineering and Technology, Aligarh Muslim University, Aligarh 202 002, India
2Higher Institute of Engineering, Hoon, Libya

Received 24 November 2010; Revised 23 January 2011; Accepted 10 February 2011

Academic Editor: Hakan Arslan

Copyright © 2011 Uzma Aisha et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The kinetics of the reduction of colloidal MnO2 by glyphosate has been investigated spectrophotometrically in an aqueous and micellar (cetyltrimethylammonium bromide, sodium lauryl sulfate) media. The reaction follows first-order kinetics with respect to colloidal MnO2 in both the aqueous and micellar media. The rate of oxidation increases with increase in [glyphosate] in the lower concentration range but becomes independent at its higher concentrations. The addition of both the anionic (NaLS) and cationic (CTAB) micelles increased the rate of reduction of colloidal MnO2 by glyphosate while the nonionic TX-100 micelles did not influence the rate of reaction. In both aqueous and micellar media, the oxidation of glyphosate occurs through its adsorption over colloidal MnO2 surface. The reaction in micellar media was treated by considering the pseudophase model. The values of reaction rates and binding constants in the presence of micelles were determined.