Layer-by-Layer-Assembled Loose Nanofiltration Membrane for Persulfate Activity Enhancement: Performance and Process Regulation

Abstract

In this study, a Prussian blue analogue (PBA)-intercalated magnesium aluminum hydrotalcite (PBA–LDH) material was used to successfully modify the membrane surface by layer-by-layer synthesis with an intermediate layer inspired by dopamine polymerization (polydopamine (PDA)). The PBA–LDH@PDA membrane was endowed with highly efficient peroxymonosulfate (PMS) activation and superb antifouling properties. Quenching experiments implied that SO4 •– mainly contributed to the sulfadiazine (SDZ) degradation in the PBA–LDH@PDA membrane-activated PMS system and performed well under various conditions. On the other hand, the PBA–LDH@PDA membrane was confirmed to exhibit separation by loose nanofiltration. The fouling performance of the membrane identified an extremely low flux attenuation even when 60 mg/L bovine serum albumin (BSA) was filtered. Multicycle filtration experiments demonstrated extremely low fouling accumulation of the membrane. The loose nanofiltration membrane with PMS activation properties possesses multiple advantages: activation of PMS by the filtration process provides a space in which the catalyst, oxidant, and foulant can completely react; the two goals of fouling mitigation and target foulant removal can be mutually realized by controlling the operating parameters (e.g., PMS dosage and filtration pressure). Overall, this study provides a beneficial strategy for improving the efficiency of membrane filtration and foulant removal.

Loose Nanofiltration Membrane Incorporating CeZnFe Layered Double Hydroxide with Enhanced Dye/Salt Separation Performance and Self-Cleaning Ability

“…Moreover, it has been reported that AM-PEI/HPAN LNF membranes showed resistance to membrane fouling with a flux recovery rate of over 98% [ 15 ]. While there have been numerous studies on LNF membranes, further evaluation and research are still needed to enhance their water flux performance, antifouling capabilities, and photocatalytic properties [ 16 , 17 ]. Continued research efforts can lead to the development of more efficient and versatile LNF membranes with enhanced performance in these critical aspects.…”