通过红外光谱在线监测强酸催化下硝酰胺、甲醛和氨水合成二硝基五亚甲基四胺(DPT)的反应过程,利用渐进因子分析(EFA)、直观推导式演进特征投影法(HELP)和多元曲线分辨-交替最小二乘法(MCR-ALS)等化学计量学方法对反应过程获得的红外光谱信息进行解析,得到了各组分纯物质的浓度变化曲线和对应的红外光谱,并把多元曲线分辨-交替最小二乘法与直观推导式演进特征投影法的分析结果进行比较,得出可相互验证的一致结论,以此推测出该反应合理的反应机理.化学计量学方法对在线红外光谱信息的分辨可以快速有效地反映DPT合成过程中各组分的浓度和红外光谱变化情况,对其反应机理研究具有重要指导意义.
Infrared spectroscopy is used to on-line monitor the reaction process of synthesizing dinitropentamethylenetetramine (DPT) from nitrate amide,formaldehyde and ammonia in the catalysis of strong acid.The concentration profiles and spectra of reactants,intermediates and products are determined by analyzing the IR data using chemometric methods [principal component analysis (PCA);evolving factor analysis (EFA);multivariate curve resolution-alternating least squares (MCR-ALS);heuristic evolving latent projection (HELP)],and the reasonable mechanism is induced by the same conclusion obtained from comparing MCR-ALS with HELP.The results show that the concentration variation and IR spectra of the components during the reaction process can be obtained effectively and efficiently with the aid of chemometric resolution and provide significant guidance to the study of the reaction mechanism.