Experimental determination of four characteristics used to predict the retention of a ceramic nanofiltration membrane

Pore size analysis from retention of neutral solutes through nanofiltration membranes. The contribution of concentration–polarization

“…(11) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 -19-speed, because this set is the closest to turbulent regime that was assumed in the mass transfer model in Eq. (16). Using the parameters fitted for the case of turbulence, the estimated observed retention for low stirring speeds (60 and 300 rpm) does not correspond at all with experimental values.…”

“…The transport through the membrane, and the transfer control of a solute can be studied from different points of view: hydrodynamics, electrostatic and thermodynamics [16]. In our case, the hydrodynamic model will be used to characterize the behavior of the membrane to uncharged solutes, assuming that membrane pores are straight and cylindrical in shape and the molecules of solute are substantially spherical.…”

Modélisation du transport des solutés neutres à travers des membranes de nanofiltration

“…Le côté intermédiaire de la nanofiltration vis-à-vis de l'osmose inverse et de l'ultrafiltration a longtemps fait que cette équation ou une de ses formes déri-vées, ont été utilisées pour décrire les mécanismes de transfert pour ces membranes (COMBE et al, 1997 ;SARRADE étal., 1994 ;BOWEN étal., 1997). Lors de la position des hypothèses, on a supposé que la diffusion avait un rôle prépon-dérant dans le transport des espèces.…”

“…The simple one-parameter model was successful in correlating the results obtained in this work. The model was also tested with data coming from COMBE et al (1997), who studied filtrations of glucose, saccharose and rafflnose in a laminar flow System by ceramic nanofiltration membranes laid out in the shape of tubular module. The results obtained show that the simple model also successfully correlates with the performances of thèse membranes.…”

Rejection of Bromide and Bromate Ions by a Ceramic Membrane

“…The surface of ceramic membranes is typically charged, as the surface of metal oxides from which they are made are usually charged, due to the amphoteric nature of the surface hydroxyl groups on the metal oxide surface (Tsuru, 2001). Previous studies have shown that due to their surface charge, ceramic ultrafiltration (UF) or NF membranes can reject ions, even though the pore size of the membrane is much larger than the size of the ions (Combe et al, 1997;Fievet et al, 2002;Labbez et al, 2003;Skluzacek et al, 2006). Charge effects are largely responsible for the rejection of the ions.…”