Pore structure control of phenol-formaldehyde based carbon microfiltration membranes

A novel method for the control of pore structure of the phenol-formaldehyde (PF) based carbon microfiltration membranes was discussed. The PF novolak resin was used as raw material with hexamine as curing agent. The pore size distribution of the carbon membranes was tested by the bubble point method with isopropanol-nitrogen as wetting-permeating system. The morphology of the membrane from partially cured resin was porous and uniform, while that of carbon membrane from resin without curing was dense with few large pores. The results show that the pore size distribution of membranes with low hexamine content at partially cured stage was sharper than that of membranes with a high hexamine content.