速率常数-秩分析法在化学反应过程分析中的应用

Application of Rate Constant-Rank Analysis in the Process Analysis of Chemical Reaction

针对化学反应动力学谱 -吸收光谱组成的两维数据 ,提出了以优化速率常数而消去反应物波谱信息为减秩手段的速率常数 -秩分析法 (RCRA) .结果表明 ,RCRA在一次优化过程中可同时获得两个最优解 ,分别对应于两步速率常数 .在获得动力学参数的前提下 ,利用最小二乘回归可解出包括中间体在内的各组分的吸收光谱 .该方法用于处理苯胺电解降解的两维数据 ,发现苯胺降解过程中有一种表观中间体存在 。

Two way matrix of kinetic spectroscopic data is obtained after measuring a series of absorption spectra during the process of chemical reaction. A method 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, RCRA has 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. RCRA has 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.