Role of cationic gemini surfactants (m-s-m type) on the oxidation of D-glucose by permanganate

Cationic gemini (m-s-m type; m = 16, s = 4,5,6) surfactants were used to determine the micelles assisted kinetics parameters, mechanism of permanganate-D-glucose redox system in an aqueous solution by means of UV visible spectroscopy at 40 degrees C. Effects of different [gemini surfactant], [permanganate], [D-glucose] and temperature on the reaction rate were investigated. Various activation parameters such as activation energy (Ea), enthalpy of activation (Delta H#), free energy of activation (Delta G#), and entropy of activation (Delta S#) have been evaluated. Menger-Portony pseudo-phase model modified by Bunton was used to analyze the role of gemini surfactant on the rate constant. Spacer chain length of surfactants has significant impact on the oxidation-reduction kinetics. A suitable mechanism reliable with the experimental results has been proposed and discussed. The cationic gemini surfactant micellar media are relatively more efficient than conventional monomeric surfactant i.e. cetyltrimethylammonium bromide (CTAB). (C) 2016 Elsevier B.V. All rights reserved.