High-performance Ceramic Supported Thin Film Composite Membrane for Organic Solvent Nanofiltration

The commercial success of membrane-based separations processes related to water treatment have helped launch an emergent field of membrane based organic solvent nanofiltration (OSN). Polyamide, a mainstay selective layer found in reverse osmosis (RO) membranes, has demonstrated some excellent performance in OSN. RO membranes, however, are built on solvent intolerant polymers (polysulfone), thus necessitating the use of polyamides on other types of supporting materials. One such support material is a ceramic ultrafiltration membrane. In this work, we demonstrate the formation of a polyamide selective barrier layer in-situ onto a ceramic UF membrane and evaluate the think film composite for use in OSN. We have selected ceramic tubular UF membranes provided by Fraunhofer IKTS as substrates for this work. The resulting membranes, after activation with dimethylformamide, have demonstrated a pure methanol permeance of 26.3 Lm^-2h^-1bar^-1, and dye rejection for methyl orange (327.3g/mol), acid fuchsin (585.5g/mol), chlorophyllin (724.2g/mol) and brilliant blue (825.6g/mol) of 30 %, 90%, 95%, and 91%, respectively. This work represents the first time that polyamide selective layers have been directly formed onto a tubular ceramic membrane and tested for OSN.