Kinetics of cyanuric chloride hydrolysis in aqueous solution

The hydrolysis of cyanuric chloride is investigated as a function of temperature, pH, and cyanuric chloride concentration in liquid phase. The hydrolysis reaction is carried out in water or acetone/water system in the temperature range of 283.15-303.15 K. The hydrolysis rates of cyanuric chloride are monitored at different temperatures and at various pHs. The experiment data show that the hydrolysis rates are independent of pH value when pH <= 6, and increase with the pH value when pH >= 7. On the basis of the results, it is supposed that the hydrolysis reaction takes place by the unimolecular nucleophilic substitution (S(N)1) mechanism when pH <= 6 and by the bimotecular nucleophilic substitution (S(N)2) mechanism when pH >= 7. Kinetics models corresponding to the mechanisms are proposed as follow: -d(n(A)/v)/dt = 7.625 x 10(9)e(-69298/RT) c(A) for the acidic situation and -d(n(A)/v)/dt = 7.112 x 10(11)e(-59267/RT) c(A)c(B)(0.5) for the alkaline situation. Experiment data show that the models work well with the average deviations of 2.01% and 9.88%, respectively.