A comparison of membrane charge of a low nanofiltration ceramic membrane determined from ionic retention and tangential streaming potential measurements Original Research Article

The retention of neutral solutes and ionic solutions on a NF ceramic membrane was measured. The Donnan Steric Pore Model (DSPM) was fitted to these observations yielding effective pore radius (rp) and thickness/porosity ratio (Δx/Ak) from neutral solutes data and the effective volume charge (X) from electrolyte data. Effective volume charges were also directly determined using tangential streaming potential measurements. The DSPM gives X in good agreement with the values obtained by streaming potential. However, it overestimates Δx/Ak compared to the value deduced from neutral solute retention.