Tailoring pore structure and surface chemistry of microporous Alumina-Carbon Molecular Sieve Membranes (Al-CMSMs) by altering carbonization temperature for optimal gas separation performance: An investigation using low-field NMR relaxation measurements
Author/s
Forster, Luke; D'Agostino, Carmine; Anabell Llosa-Tanco, Margot; Spallina, Vincenzo; Brencio, Camilla; [et al.]Date
2021Keywords
Carbon membranes
Water selective membrane
Low-field NMR
NMR relaxation
Abstract
In this work we applied low-field, NMR spin-lattice measurements to evaluate for the first time the effect of carbonization temperature (range 600 - 1000 ℃) on the preparation of Alumina-Carbon Molecular Sieve Membranes (Al-CMSMs), providing new insights into intra-pore fluid interactions. The results show that the average Al-CMSM pore size generally increases with carbonization temperature whilst the hydrophilicity of the pore surface, and the amount of strongly adsorbed H2O, decreases with an increasing carbonization temperature. As such, lower carbonization temperatures produce more hydrophilic membranes, with further evidence provided by FTIR measurements demonstrating the presence of polar functional groups on the surface, with water interacting more strongly with the membrane surface, as evidenced by NMR.
It was found that the Al-CMSM carbonization temperature significantly affected permeance and H2O/CH4 permselectivity by altering the membrane pore size distribution and pore ...
Type
article