Modeling of Fouling and Fouling Attachments as a Function of the Zeta Potential of Heterogeneous Membrane Surfaces in Ultrafiltration of Latex Solution

The aim of the present study was to develop a fouling attachment model applicable for both hydrophilic and hydrophobic nonuniform pore size membranes. The predictive models found in the present study allow for an accurate estimation of the depositional and coagulation attachments, at a given operating condition and membrane surface charges. The effect of the zeta potential of the membrane surface on the fouling attachments, the total mass of fouling, the permeate flux, and the specific power consumption in ultrafiltration of a latex solution was also investigated. Polysulfone flat membrane with a MWCO of 60 000 at different surface charges was used under a constant flow rate and cross-flow mode in ultrafiltration of the latex paint solution. Response Surface Methodology (RSM) was implemented throughout the experimental design. Furthermore, hydrophilic ultrafilic and cellulose acetate membranes at different zeta potentials, as well as hydrophobic PVDF membranes, were used to test the reliability and accuracy of the predictive models. The fouling model and the correlations found in the present study form a comprehensive set of predictive models that allow for the estimation of the mass of fouling and the increase in transmembrane pressure, applied to both hydrophilic and hydrophobic membranes of a variety of materials with different molecular weight cutoff (MWCO) values.