College Mech Eng, Changzhou University, Changzhou, Jiangsu Province, China
The performances of the optimized tree-type cylindrical-shaped nanoporous fltering membranes with six or seven branch pores in each pore tree are analytically studied. The radius Rb,1 of the branch pore for fltration is normally on the 1 or 10 nm scales. The larger trunk pore is for improving the ﬂux of the membrane. For liquid-particle separations, the radius Rb,1 of the branch pore is determined by the particle size, and the radius Rb,2 of the trunk pore is optimized for yielding the lowest ﬂow resistance of the membranes; The optimum ratios of Rb,2 to Rb,1 are typically calculated respectively for weak, medium-level and strong liquid-pore wall interactions when the operational parameter values are widely varied. The capability of the liquid-liquid separation of these membranes is also analytically shown.