Abstract: According to the theoretical basis of thermokinetics, the integral and differential thermokinetic equations of consecutive first order reaction have been-deduced, and the mathematical models of the time parameter method for consecutive first order reaction have been established in this paper. Only needing the characteristic time parameter t_m, 2 t_m and 3 t_m and the corresponding thermoanalytical data from the same curve, the rate constants of the two steps can be determined simultaneously. Additionally, a novel method to determine the values of d Δ /dt by using the time parameter t_m, the peak height Δ m at time t_m and the total area of the curve, rather than by the use of slop from thermoanalytical curve at time t-with differential method, is proposed. The thermokinetics of saponifications of diethyl phthalate and diethyl adipate in aqueous ethanol solvent has been studied and the validation of the theory and method of the time parameter method for consecutive first order reactions is verified by the experimental results.

Key words: Thermokinetics, Thermokinetic research method, Time parameter method, Consecutive first order reactions