Optimizing operating conditions for olive leaf valorization using activated carbon mixed matrix membrane

Olive leaf extract (OLE) processing via membrane filtration often faces challenges in effectively separating total phenolic compounds (TPCs) while maintaining a high permeate flux and minimizing impurities, highlighting the urgent need for advances in membrane technology. This issue is addressed by preparing polysulfone/activated carbon nanoparticles (Psf/AC) mixed matrix membranes (MMMs) using a phase inversion technique. Impact of AC concentration on structure and efficiency of membrane was studied. The contact angle decreased from 66.7 degrees (in the pristine Psf) to 48.2 degrees in the membrane containing 0.9 % AC. Hydraulic permeability increased by 47.55 % with 0.6 % AC addition. The efficiency of prepared membranes in separating of TPC from olive leaf extract (OLE) was evaluated under various pressures. The membranes based on 0.3 % AC demonstrated significantly improved performance, exhibiting a flux of 11.8 L m- 2 h-1, surpassing the pristine membranes by more than double their flux (4.8 L m- 2 h-1), while also showing enhanced rejection of TPC. Furthermore, these membranes achieved over 97 % water permeability recovery after OLE filtration and subsequent cleaning. The rejection of TPC was examined using a 0.3 % AC -based membrane through a central composite design (CCD), considering feed pH, temperature, and pressure as three variables, each with three levels. The rejection TPC was observed to increase under conditions of highly acidic pH (2.7) and low temperature (25 degrees C), along with elevated pressure (30 bar). This study developed AC -based NF membranes novel application in TPC separation from OLE, achieving 100 % oleuropein (OLP) rejection under optimal conditions using 0.3 % AC -based membranes.