The best polymeric ultrafiltration membranes used (good photostability checked by SEM and TOC, acceptable values of wpf, rejection unfortunately negligible etc.):
¾ ¾ ¾
PAN (polyacrylonitrile) FS50PP (fluoride + polypropylene) GR51PP (polysulfone + polypropylene).
In order to improve the rejection effects, polymeric nanofiltration membranes were used in the systems 4a and 4b. The best ones were NF-PES-010 (more permeable, polyethersulfone, Hoechst) and N30F (less permeable, modified polysulphone, Hoechst).
The choice of the membrane depends on the size of the pollutants to be treated. pH can influence very strongly the rejection (Donnan Exclusion).