A study on the hydrolysis of bis(nitrophenyl)phosphate catalyzed by N-methyl-diethanolamine-Ce(III) complex

The hydrolysis of bis(p-nitrophenyl)phosphate (BNPP) catalyzed by N-methyldiethanolamine-Ce(Ill) complex in the presence and absence of cetyltrimethylammonium bromide (CTAB) and Brij35 surfactants at pH 7.20 and 303 K has been studied. The experimental results indicate that N-methyldiethanolamine-Ce(III) complex remarkably accelerates the hydrolysis of BNPP. The observed first-order rate constant of the hydrolysis of BNPP catalyzed by N-methyldiethanolamine-Ce(III) complex at pH 7.20 and 303 K is 1.22 x 10(-2) s(-1), which is 1.09 x 10(9) times of that of spontaneous hydrolysis of BNPP at pH 7. It is close to the activity of natural enzyme. A general quantitative treatment of the catalytic reaction involved a ternary complex as MmLIS has also been proposed in this paper. Applying this method to the catalytic hydrolysis of BNPP, we have obtained its thermodynamic and kinetic parameters. CTAB and Brij35 surfactant micelles obviously influence the rate constants of the catalytic hydrolysis of BNPP. Brij35 micelles promote the catalytic hydrolysis of BNPP, while CTAB micelles inhibit it. (C) 2004 Wiley Periodicals, Inc.