Structural Changes and Operational Deterioration of the Uf Polyethersulfone (Pes) Membrane Due to Chemical Cleaning.

Microfiltration (MF) and ultrafiltration (UF) membranes are capable of rejecting most of particulate and colloidal matter from natural water. The major impediment to their applications is fouling caused by contaminants that accumulate on and/or inside the membrane. Therefore, most membranes are subjected to chemical cleaning procedures as one of the methods to control fouling. Exposure to chemical cleaning agents can reduce the performance and lead to the degradation of polyethersulfone (PES) ultrafiltration membranes. This study was conducted in order to evaluate the effect of cleaning agents on the properties of the PES membranes during exposure to short-term foulant and a cleaning agent. The cleaning agents evaluated were NaOH, HCl and NaOCl. The accelerated static cleaning conditions showed significant changes in PES flat sheet membrane properties in case of cleaning with NaOCl. These changes were analyzed using SEM microscopy, FTIR spectroscopy, contact angle measurement and hydraulic membrane performance evaluation.