Ultra Filteration Membranes: Ultrafiltration membranes are capable of separating larger materials such as colloids, particulates, fats, bacteria, and proteins, while allowing sugars, and other low molecular weight molecules to pass through the membrane.With a pore size range between 0.01 to 0.1m, ultrafiltration membrane pore sizes fall between that of nanofiltration and microfiltration. UF membranes typically operate between 50 120 PSI (3.4 8.3 bar) and are dependent on transmembrane pressure to drive the separation process. Other polymeric ultrafiltration membrane characteristics include robust chemical and temperature resistance, and low fouling tendencies if proper pretreatment is employed.