Effect of Non-Solvent Additives to the Casting Solution on the Structure and Properties of Polyethersulfone UF Membranes

Document Type : SI: MEMTEK2019

Authors

1 Institute of Physical Organic Chemistry, National Academy of Sciences of Belarus

2 13 Surganov street

3 The A.V. Luikov Heat and Mass Transfer Institute, National Academy of Sciences of Belarus

Abstract

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.

Graphical Abstract

Effect of Non-Solvent Additives to the Casting Solution on the Structure and Properties of Polyethersulfone UF Membranes

Highlights

• Structure and properties of UF membranes depend on the
precipitation value of NSA
• The higher the PV of NSA, the higher PWF of membranes with the
spongy structure
• Membranes with max. performance are obtained when α*= 0.52-
0.81

Keywords

Main Subjects