Ionic liquid regulated interfacial polymerization process to improve acid-resistant nanofiltration membrane permeance

Ionic liquids membranes for liquid separation: status and challenges

“…Thus, this membrane could be used in the recycling and removal of compounds in low pH conditions and even extremely acidic environment. 122 Moreover, Naik et al prepared a poly(ionic liquid)-based anion exchange membranes for acid recovery from industrial wastewater/effluent. 119 a The PIL-based membrane demonstrated excellent acid dialysis coefficient and separation factors due to the development of a highly conductive layer and efficient ion migration channels formed at the interface of the polymer–polymer.…”

Catalytic template assisted interfacial polymerization for high‐performance acid‐resistant membrane preparation

“…Sufficient attempts have been made to continuously innovate chemical stable monomers to meet more extreme conditions. However, to avoid selective layer defects caused by the poor reactivity of acid stable monomers, the fabricated selective layers are relatively thick (>100 nm), resulting in a low permeance, which definitely increases the equipment and operating costs 12–16 . Therefore, acid‐resistant NF membranes with high permeance and similar separation layer thickness to conventional PA membranes are appealing in acidic streams treatments.…”

Retarded Interfacial Formation of Polyamine-Based Nanofiltration Membranes with Pyromellitic Acid: Separation, Acid Stability, and Antifouling Performance

“…Moreover, one of the increasing areas of NF membrane application is in acid wastewater treatment and reclamation processes. , Recently, polyethyleneimine (PEI) and cyanuric chloride (CC) have been used as reactants in preparing acid-stable NF membranes to meet these demands. ,− Their formation usually results in a tight polyamine network with good separation performance and robust chemical stability, especially in extreme conditions. , More importantly, their (i.e., PEI/CC combination) physicochemical properties and acid stability have been proven to further improve when synthesized during IP with crosslinkers, phase catalysts, surfactants, and green solvents. ,− However, none of these studies have paid attention to the synergetic relationship between the IP-modified membranes and their performances toward both acid exposure and fouling resistance properties. As wastewater with acid contents may often contain some inorganic impurities that could easily foul the membrane surface while in use, it is therefore imperative to factor in how this problem can be solved, even at the membrane preparation stage in order to fabricate a sustainable and structurally stable NF membranes with good antifouling performance for emerging environmental applications in water and wastewater treatment/recovery.…”

“…It has been established that the IP reaction of PEI and CC rapidly formed a crosslinked network that is very tight and hence results in low permeability. ,, However, introducing PMA to “temporarily” slow down the diffusion of BPEI with CC during IP will help to regulate the cross-linking reaction, thereby forming a relatively loose network that favors permeability. Therefore, in this study, PMA was engaged with an active amino cationic group (BPEI) and s-triazine ring-based (CC) reactants in an interfacial reaction for the first time to form a relatively loose polyamine NF membrane network structure.…”