Antagonism in (conventional anionic–gemini anionic) mixed micelle catalyzed oxidation of D‐fructose by alkaline chloramine‐T: A kinetic study

Abstract

The catalytic effect of individual conventional anionic surfactant, namely, sodium lauryl sulfate (NaLS), anionic gemini surfactant, namely, sodium salt of bis(1-dodecenyl succinamic acid) (NaBDS), and mixed surfactant (NaLS + NaBDS) on the rate of oxidation of D-fructose by alkaline chloramine-T has been investigated. The reaction always showed a firstorder dependence of rate with respect to each fructose, alkali, and chloramine-T. The rate was proportional to (k + k [surfactant]), where k and k are the rate constants in the absence and presence of the surfactant, respectively. The binding parameters have been evaluated. The observed catalytic effect of mixed micelle on the rate of oxidation was always less than the algebraic sum of the catalytic effect of two surfactants when they were taken separately, suggesting an antagonism (negative synergism) in mixed micelle. The antagonism has also been confirmed by determining critical micelle concentration and interaction parameter (β m ) of mixed micelle under the experimental conditions of kinetics, that is, in alkaline medium.

Physicochemical Properties and Supernucleophilicity of Oxime-Functionalized Surfactants: Hydrolytic Catalysts toward Dephosphorylation of Di- and Triphosphate Esters

“…Slight antagonism in the case of 3-C 10 to 3-C 14 mixed systems can also be explained on the basis of less difference in the cmc values of individual components whereas in the higher chain lengths cmc difference was much pronounced. 47 Table 2 shows micellar parameters of 3-C 12 + CPB system studied at different mole fractions (0.2, 0.5, and 0.8) by conductivity and surface tension measurements at 300 K and pH 7.1. The results are also depicted in Figure 4.…”

“…Increase in the hydrophobic tail length of 3-C n might have increased the hydrophobic character of the core coupled by the neutralization of polar headgroup repulsions and this might have generated synergism. Slight antagonism in the case of 3-C 10 to 3-C 14 mixed systems can also be explained on the basis of less difference in the cmc values of individual components whereas in the higher chain lengths cmc difference was much pronounced …”

Kinetics of brilliant green fading in the presence of TX-100, DTAB and SDS

“…The rates of chemical reactions are known to be changed by self-organized assemblies such as micelles [1][2][3][4][5][6][7][8][9]. Effects of micelles on these reactions can be attributed to electrostatic and hydrophobic interactions.…”

Effects of Surfactants on the Rate of Chemical Reactions

“…(anionic gemini surfactant), and mixed surfactants (SDS + NaBDS) on the oxidation rate of D-fructose by alkaline chloramine-T have been investigated [16]. The observed catalytic effect of mixed micelle on the oxidation rate was always less than the combination of the catalytic effects of two individual surfactants, suggesting an antagonism (negative synergism) in the mixed micelle.…”