(288d) High-Performance Ceramic Supported Thin Film Composite Membrane for Organic Solvent Nanofiltration

Aromatic polyamide is a common material used as selective layers for thin film composite (TFC) reverse osmosis (RO) membranes. This material has also demonstrated excellent performance in organic solvent nanofiltration (OSN). RO membranes, however, are built on solvent intolerant polymers that can dissolve or swell in the presence of many solvents. This necessitates the use of solvent tolerant supports for TFC membranes designed for OSN. Ceramic membranes offer solvent resistance, but forming polyamides on ceramic substrates has been challenging because ceramic membrane pore sizes have typically been too large to support the thin and fragile polyamide layer. With the recent advances in ultrafiltration ceramic membranes by Fraunhofer IKTS, the pore sizes have been reduced to a size that is more in line with conventional polymeric membranes used to support polyamide selective layers in RO,. In this work, we demonstrate the formation of a polyamide selective barrier layer in-situ onto a ceramic UF membrane and evaluate the TFC for use in OSN. We have selected ceramic tubular UF membranes provided by Fraunhofer IKTS as substrates. The resulting membranes 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.