Dynamic ultrafiltration model for proteins: A colloidal interaction approach

Electrofiltration of Biopolymers

“…These interactions depend on London-van der Waals forces, hydration forces, electrostatic forces and configurational entropic effects [16]. Electrostatic and van der Waals interactions are the best known effects, forming together the basis of DLVO theory [17]. Nakamura [77] reports that electrostatic effects play an essential role in the interactions between many biologically important molecules.…”

“…According to investigations by other authors these interactions cannot be defined by means of a single effect. For the filtration experiments with BSA, Bowen [17] predicted the filtration rates of protein solutions based on their physicochemical properties. For proteins they demonstrated also that the configurational entropic effect becomes more important with the decrease in the colloids' size.…”

Quantitative predictive modelling of ultrafiltration processes: Colloidal science approaches

“…The space charge in the electrolyte is now divided into two regions: (a) the compact or inner region very near the particle surface (up to the OHP) and (b) the diffuse layer where the PBE applies. The detailed structure of the inner region of the double layer is not directly important in the modelling of ultrafiltration processes [3,4], but the method by which the distance to the OHP is calculated will depend on the type of model used for describing the compact region. The position of the OHP is important as this is widely assumed to lie coincident with or very near to the surface of shear at which the zeta potentials are calculated from electrophoretic mobility data [2].…”

Properties of the Cake Layer in the Ultrafiltration of Polydisperse Colloidal Silica Dispersions

“…Performance of the developed membrane can be optimized by knowing some useful information observed in a SEM. A number of studies have been conducted on AFM characterization related to membrane analysis (Bessibres et al 1996;Binning et al 1982;Bowen et al 1996a; Bowen et al 1996b;Bowen et al 1998a;Bowen et al 1998b). The AFM can be used to give high resolution nanometer scale images of the topography of a range of surfaces with little surface preparation and no surface coating.…”

“…This type of the membrane process is capable of separating the solutes with a molecular weight greater than 1000 Da (Coulson et al 2002). Many works have been reported on the flux decline in ultrafiltration (Bowen and Jenner 1995;Bowen and Williams 1996a;Shen and Probstein 1977;Wijman et al 1984) but only a few studies have been reported in the literature on modelling the behaviour of polydisperse feeds containing suspended colloidal particles (Dickinson 1979;Dickinson et al 1988;McDonogh et al 1998). Studies on the effect of polydispersity on the rate of filtration have been conducted by researchers in order to introduce a new parameter into the classic filtration model to consider for polydispersity effect (Mc Donogh et al 1998, Dickinson, 1979).…”