Mass transfer across boundary layers in non-ideal systems

This research fundamentally studied polydimethylsiloxane (PDMS) membrane pervaporation process related steady state isothermal behaviors and diffusion behaviors by using many commonly used organic solvents under wide range concentration conditions. The objective of this study is to evaluate the possibility of using membrane introduction mess spectrometry (MI-MS), coupling membrane (function as interface) with mass spectrometer, to monitor liquid phase organic chemical reactions in real-time.; The major concern of using polymer membrane interface between organic process and mass spectrometer is the properties of the membrane. It gave linear behaviors for many tested binary organic/water and organic/organic systems at lower concentrations. However, at higher organic concentrations, this dens rubber polymer membrane intrinsically behaved non-linearly. It gave many types of different isothermal behaviors such as Flory-Huggins behavior and Langmuir type of non-permeable adsorption behaviors, some of these behaviors related to membrane swelling. The Hildebrand solubility parameters and linear solvation energy relationship (LSER) was found useful for predicting polymer membrane pervaporation behaviors.; It is proved that many commonly used organic solvents actually do not or only slightly swell cross-link grade PDMS membrane in this study. Some simple reactions were monitored in real-time by using MI-MS and which were successful. But there are many concerns on solvent-membrane, solvent-analyte, analyte-membrane interactions caused non-linearity, and bend broadening during real-time monitoring. Further development of different types of membrane and improvement of current membrane interfaces are essential for MI-MS to be practically used in this area.