According to the theoretical basis of thermokinetics, a self-- function recursion equation of irreversible consecutive first-order reactions has been derived and a novel thermokinetic research method - ---self-function regression method for consecutive first-order reactions, which can be used to determine the rate constanst of two steps stimultaneously, has been proposed in this paper. In order to test the validity of this method, the saponifications of diethy phthalate and diethyl succinate in aqueous ethanol sovent have been studied. The rate constants caculated with this method are in agreement with those published in literature, and therefore, the self- function regression method for consecutive first--order reactions is believed to be correct.

Key words: THERMODYNAMICS, DIETHYL SUCCINATE, SAPONIFICATION, REACTION RATE CONSTANT