Abstract
The hydrolysis reactions of 4-nitrophenyl diphenyl phosphate, 4-nitrophenyl di-4-tolyl phosphate, and diethyl 4-nitrophenyl phosphate (paraoxon) have been studied in hexadecyltrimethylammonium anti-pyruvaldehyde 1-oximate (C16TAOx) buffer solutions prepared by 1:2 mixing of hexadecyltrimethylammonium hydroxide with anti-pyruvaldehyde 1-oxime, thus allowing the avoidance of counterion inhibition effects observed when using conventional cationic surfactants. The reactions are strongly accelerated by the C16TAOx micelles, and the half-life for the persistent insecticide paraoxon is as low as 2 min at [C16TAOx] = 10-2 M. The data are discussed in terms of the pseudophase ion-exchange (PIE) model. However, this model is not sufficient to explain that the rate constants increase significantly when sodium oximate is added and that KCl and NaOAc salt effects exhibit S-shaped curves. Conductivity data suggest some minor variations in the degree of counterion association, β, but these variations are too small to ac...
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have