Intrinsic properties and performances of NF270 and XLE membranes for water filtration

• Published in: Water science & technology. Water supply Vol. 11; no. 2; pp. 186 - 193
• Main Authors: DIOP, S. N, DIALLO, M. A, DIAWARA, C. K, COT, D
• Format: Journal Article
• Language: English
• Published: London International Water Association 01.01.2011; IWA Publishing
• Subjects: Applied sciences; Atomic force microscopy; Buildings. Public works; Drinking water; Electron microscopy; Exact sciences and technology; Low pressure; Membrane permeability; Membranes; Nanofiltration; Nanotechnology; Permeability; Pressure; Reverse osmosis; Roughness; Scanning electron microscopy; Water filtration; Water purification; Water supply. Pipings. Water treatment; Zeta potential; Removal; Performance evaluation; Atomic force microscopy; Scanning electron microscopy; Water filtration; Measurement result; Theoretical study; AFM; Osmosis; zeta potential; Fluorides; Permeability; Experimental study; Nanofiltration; Experimental result; Membrane; Electrokinetic potential; SEM
• ISSN: 1606-9749; 1607-0798
• DOI: 10.2166/ws.2011.024

Nanofiltration and low pressure reverse osmosis membranes are well-known in the field of drinking water production and their separation performance is very strongly related to their intrinsic characteristics. The membrane characterization (scanning electron microscopy (SEM), atomic force microscopy (AFM), zeta potential ...) was realized on a NF270 and extra-low energy (XLE) membrane. SEM results of virgin NF270 and XLE membranes show that both are about the same thickness whereas that of the active layer of NF270 membrane is weaker than that of the XLE. The AFM measurements show that the roughness of the low pressure reverse osmosis membrane (XLE) is almost 20 times as high as that of nanofiltration (NF270). Zeta potential measurements showed that both membranes are negatively charged in pH (4--12) range. An increase in permeability by increasing feed pressure and temperature was also noted for the two types of membrane; but the permeability evolution for XLE membrane according to the volume factor reduction reveals a fall faster than that of NF270.