Micellar effects on the reduction of Orange-11 by sulphite ions

Abstract

The kinetic studies on the reduction of Orange-II by sulphite ion in a buffer medium of pH 7.0 revealed that the reaction is first order with respect to Orange-11 and sulphite ion concentrations. A suitable mechanism is proposed based on the results. Cationic surfactant cetyltrimethyl ammonium bromide (CTAB) catalysed the reduction by 23 times whereas anionic surfactant sodium dodecyl sulphate (SDS) and nonionic surfactant polyoxy ethylene (23) dodecanol (Brij-35) inhibited the reduction by 4. 7 and 31 times. These effects are discussed on the basis of interactions of the above compounds and micelles of different charge type. Binding parameters have been calculated by analysinJ: the data using pseudo phase model.