Análise conformacional da estrutura molecular de misturas azeotrópicas

Abstract

The azeotropic phenomenon consists of a mixture of at least two substances which at a given concentration, temperature and pressure evaporates as a pure substance, making its complete separation impossible based only on the difference in boiling point. Its presence in the industry leads to several challenges. When it occurs, an additional separation process is required in the plant because the solvent used to break this azeotrope needs to be recycled. Thus, adding more steps increasing the overall process time. Furthermore, more stages involved mean a higher risk of accidents and to a higher energy consumption. It is important to note that there is a cost associated with the solvent, which varies depending on the components in the azeotrope, creating an external dependency on suppliers for these reagents. In this study, we analyzed the behavior of an azeotropic mixture in terms of its vibrational spectra. The goal was to assess the intensity of natural oscillations as a function of the excitation frequency of the water-ethanol mixture. By identifying the spectra of different components within the mixture, we could infer that localized excitations are possible. Consequently, electromagnetic radiation at a specific frequency can resonate with the natural oscillation of some parts of the mixture. Our study focused on both intra and intermolecular frequencies, which in both cases appear to be accessible selectively, thus facilitating the breaking of the azeotrope.