Investigation of the Performance of an Optimized Tree-Type Cylindrical-Shaped Nanoporous Filtering Membrane for Varying Operational Parameter Values

The performance of an optimized tree-type cylindrical-shaped nanoporous fltering membrane proposed in the former study is analytically investigated for varying operational parameter values. Across the membrane thickness, this membrane has two-leveled tree-structured pores including one trunk pore and the multiple branch pores. The physical properties of the surfaces of all the pores are identical. The branch pore is for fltration, while the radius of the trunk pore is optimized for achieving the lowest flow resistance of the membrane. The calculation results show that in a liquid-particle separation, the influence of the number N of the branch pores in each pore tree on the lowest flow resistance of the membrane in the optimum condition strongly depends on the radius Rb,1 of the branch pore; When Rb,1 is over 10 nm, this influence is normally very signifcant; In a liquid-liquid separation, the performance of the membrane mainly depends on the radius Rb,1, which should normally be no more than 3 nm or even more less depending on the liquid-pore wall interaction, although both a smaller N value and a greater value of the ratio of the depth of the branch pore to the membrane thickness helps to improve the separation.