Document Type: SI: MEMTEK2019
Institute of Physical Organic Chemistry, National Academy of Sciences of Belarus
13 Surganov street
The A.V. Luikov Heat and Mass Transfer Institute, National Academy of Sciences of Belarus
The obtained results in this work allow us to propose a new approach to fabricate polyethersulfone (PES) ultrafiltration (UF) membranes with desired structure and performance. It was shown that UF membranes with a spongy structure are obtained from casting solutions located near the binodal line. However, with increasing the precipitation value (PV) of non-solvent additives (NSA), the higher pure water flux (PWF) of membranes with the spongy structure was observed. UF membranes with maximum performance are obtained when degree of saturation (α* – the ratio of the NSA amount added to the polymer solution to the NSA amount which causes phase separation) α*= 0.52-0.81 (depending on PV of NSA). In this case, macrovoids will prevail in the structure of the supporting layer of membranes. The size and shape of macrovoids also depend on the PV of NSA. The higher the PV of NSA, the larger the size of macrovoids in the structure of supporting layer.