Effects of hydrogen peroxide, temperature and treatment time on degradation properties of polyethersulfone ultrafiltration membrane

Oxidative cleaning agents such as hydrogen peroxide (H2O2) and sodium hypochlorite (NaClO) used in water and wastewater treatment play an important role in the degradation and rapid aging of the polymeric membranes. In addition, when the temperature is above the maximum operating range of the membrane, it negatively affects the membrane performance. H2O2 which is also known as a green and environmentally friendly strong oxidant because of releasing only water as a by-product can provide good cleaning efficiency under temperature, but its influence on membrane aging is not fully understood. In this study, the aging of polyethersulfone (PES) ultrafiltration (UF) membrane using H2O2 under high-temperature conditions and degradation of the polymeric membrane was systematically investigated using response surface methodology (RSM). The effects of H2O2 concentration, temperature, and treatment time were tested on membrane flux, contact angle, pore size, and porosity for decomposed membrane. The results showed that normalized permeability was significantly changed approximately 2.34-folds by H2O2 concentration at an exposure dose of 5 mM and 373 K temperature. Moreover, the largest pore sizes as 161.23 nm and 160.73 nm were obtained at the conditions of 2.5 mM H2O2 concentration and 373 K temperature. The lowest contact angle (54.76 degrees) and porosity (61.88%) were obtained at the same conditions. The results depicted that H2O2 can be used for membrane cleaning with minimum membrane degradation at moderate conditions.

Automated summary

This study systematically investigated the use of hydrogen peroxide for cleaning polyethersulfone ultrafiltration membranes under high-temperature conditions. The results showed that hydrogen peroxide concentration, temperature, and treatment time had significant effects on membrane performance, with hydrogen peroxide concentration having the greatest impact on permeability.