Understanding of phenolic compound retention mechanisms on PES-UF membrane

Ultrafiltration (UF) is investigated as a possible alternative to remove organic compounds from aqueous synthetic solution. This paper presents a comprehensive study towards a better understanding of phenolic compound retention mechanisms during UF processes. Thus, removal of phenol and resorcinol was studied using a polyethersulfone ultrafiltration (PES-UF) membrane. The influence of main operating conditions (feed concentration, transmembrane pressure, and pH) on the retention was evaluated. Membrane--solute interactions were found to play an important role during the process, suggesting the adsorption of the target compounds on the PES-UF membrane. The level of adsorption was consequently evaluated by measuring the quantity of each compound per surface unit of membrane. According to the kinetic study, the pseudo-first order model was found to fit better the experimental values. The adsorption equilibrium data fit the Langmuir model. In addition, the adsorption mechanism was evaluated by the intraparticle diffusion model and appeared to be a complex mechanism.