in Wiley Online Library (wileyonlinelibrary.com) A facile method for the fabrication of amine-silica membranes with enhanced CO 2 separation performance was proposed via the thermally induced liberation of small molecules from quaternary ammonium salt. Quaternary ammoniumsilica (QA-SiO 1.5) xerogel powders/films were fabricated via sol-gel processing and their thermal stability was systematically studied using thermogravimetric mass spectrometer, Fourier transform infrared, energy dispersive spectroscopy, and positron annihilation lifetime spectroscopy analysis. CO 2 sorption performances of QA-SiO 1.5 derived xerogel powders were quantitatively compared after assigning their relevant parameters to a dual-mode sorption model. The gas permeation performances of membranes derived from QA-SiO 1.5 were evaluated in terms of kinetic diameter and temperature dependence of gas permeance, and activation energy (E p) required for gas permeation. The results indicate that liberation of the CH 3 Cl molecules from these membranes significantly improved both CO 2 permeation and CO 2 /N 2 separation capabilities. Therefore, the present study provides insight that should be useful in the development of highperformance CO 2 separation membranes via the effect of the thermally induced liberation of small molecules.
Pervaporation (PV) is a membrane technology that holds great promise for industrial applications. To better understand the PV mechanism, PV dehydrations of various types of organic solvents (methanol, ethanol, iso‐propanol, tert‐butanol, and acetone) were performed on five types of organosilica and two types of silicon carbide‐based membranes, all with different pore sizes. Water permeance was dependent on the types of organic aqueous solutions, which suggested that organic solvents penetrated the pores and hindered the permeation of water. In addition, water permeance of various types of membranes in PV was well correlated with hydrogen permeance in single‐gas permeation. Furthermore, a clear correlation was obtained between the permeance ratio in PV and that in single‐gas permeation, which was confirmed via the modified‐gas translation model. These correlations make it possible to use single‐gas permeation properties to predict PV performance.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.