TY - JOUR
T1 - Kinetic aspects of salinity stability of layer-by-layer polyelectrolyte nanofiltration membranes
T2 - Impact of soaking time, types of ions and crosslinking
AU - Chen, Jiarui
AU - He, Rongrong
AU - Chen, Hao
AU - Hu, Binjie
AU - Tokay, Begum
AU - Zhang, Yue biao
AU - He, Tao
N1 - Publisher Copyright:
© 2024 The Authors
PY - 2024/7/14
Y1 - 2024/7/14
N2 - Recent discovery of very high selectivity of Layer-by-Layer (LBL) nanofiltration (NF) membranes for mono/bivalent ions has attracted significant attention, especially for extraction of lithium from salt lake brines. Besides the exceptionally high selectivity, the salinity stability in highly saline solutions (HSS) that often occurred during NF has been largely neglected. Intuitively, because the LBL membranes are assembled in a saline background solution, the assembly disassembles in highly saline environments. To verify above argument, we reported here a comprehensive study on the performance of polystyrene sulfonate (PSS)/poly(diallyldimethylammonium chloride) (PDADMAC) and PSS/poly(allylamine) hydrochloride (PAH) LBL NF membranes in HSS by short/long term immersion and dynamic filtration. Greater binding strength of (PSS/PAH)2.5 corresponded to better salinity stability than (PSS/PDADMAC)2.5. Adsorption bridging of divalent Mg2+ with PSS altered PSS conformation and narrowing the pore size distribution. Compared to static immersion, dynamic filtration accelerated the loss of PEs from (PSS/PAH)2.5 at cLiCl = 2 mol/L, but membrane stability was improved by chemical crosslinking. This research highlighted the kinetic aspects in salinity stability and the chemical-physical behavior of polyelectrolyte complexes (PECs) in HSS. The results offer valuable insights for development of LBL NF membranes for ion separation and resource recovery.
AB - Recent discovery of very high selectivity of Layer-by-Layer (LBL) nanofiltration (NF) membranes for mono/bivalent ions has attracted significant attention, especially for extraction of lithium from salt lake brines. Besides the exceptionally high selectivity, the salinity stability in highly saline solutions (HSS) that often occurred during NF has been largely neglected. Intuitively, because the LBL membranes are assembled in a saline background solution, the assembly disassembles in highly saline environments. To verify above argument, we reported here a comprehensive study on the performance of polystyrene sulfonate (PSS)/poly(diallyldimethylammonium chloride) (PDADMAC) and PSS/poly(allylamine) hydrochloride (PAH) LBL NF membranes in HSS by short/long term immersion and dynamic filtration. Greater binding strength of (PSS/PAH)2.5 corresponded to better salinity stability than (PSS/PDADMAC)2.5. Adsorption bridging of divalent Mg2+ with PSS altered PSS conformation and narrowing the pore size distribution. Compared to static immersion, dynamic filtration accelerated the loss of PEs from (PSS/PAH)2.5 at cLiCl = 2 mol/L, but membrane stability was improved by chemical crosslinking. This research highlighted the kinetic aspects in salinity stability and the chemical-physical behavior of polyelectrolyte complexes (PECs) in HSS. The results offer valuable insights for development of LBL NF membranes for ion separation and resource recovery.
KW - Annealing
KW - Ion bridging
KW - Layer-by-layer self-assembly
KW - Nanofiltration membrane
KW - Salinity stability
UR - http://www.scopus.com/inward/record.url?scp=85198860178&partnerID=8YFLogxK
U2 - 10.1016/j.memsci.2024.123087
DO - 10.1016/j.memsci.2024.123087
M3 - Article
AN - SCOPUS:85198860178
SN - 0376-7388
VL - 709
JO - Journal of Membrane Science
JF - Journal of Membrane Science
M1 - 123087
ER -