Abstract: Two-way matrix of kinetic-spectroscopic data is obtained after measuring a series of absorption spectra during the process of chemical reaction. Amethod called Rate Constant Rank-Analysis(RCRA) is proposed in order to resolve such kind of two-way data matrix in this study. The method is based on the optimizing the reaction rate constant by annihilating two-way spectra of reactant and minimizing the residual standard deviation of residual matrix. Model of consecutive first-order reaction taken as an example, RCRAhas been employed to determine the rate constants. Due to the interdependence of kinetic spectra of three components, two results could be yielded by optimizing rate constant of the first step. It is found that the two results correspond to the first and the second step rate constants, respectively. After kinetic spectrum of each component has been obtained, the least square regression is applied to resolve the absorption spectrum of each component. Among them, the spectrum of intermediate is the most valuable because it can hardly be measured directly. RCRAhas been successfully applied to resolve simulated reaction data. Principal component analysis is employed to determine the number of absorptive components. Two-way data obtained in the electrochemical degradation of aniline has been resolved by RCRA. The result indicates that there exists an intermediate in the degradation and the reaction accords with consecutive reaction.

Key words: Rate Constant-Rank Analysis(RCRA), Two-way kinetic-spectroscopic data, Consecutive reaction, Degradation of aniline