Bridged organosilica membranes incorporating carboxyl-functionalized cage silsesquioxanes for water desalination

Bis(triethoxysilyl)ethane (BTESE)–Organosilica Membranes for H2O/DMF Separation in Reverse Osmosis (RO): Evaluation and Correlation of Subnanopores via Nanopermporometry (NPP), Modified Gas Translation (mGT) and RO Performance

“…where (w ,DMF f − w ,DMF p ) is the concentration difference between feed and permeate. The osmotic pressure, π, is defined based on the activity, a (=γx), as shown in Equation (9). In Equation (9), R is the gas constant, 8.314 J mol −1 .…”

“…Many inorganic nanoporous membranes such as zeolites [ 5 , 6 , 7 , 8 ] and organically bridged silicas [ 9 , 10 , 11 , 12 ] have been studied both theoretically and experimentally for their ability to reject ions in reverse osmosis for the purpose of separating salt from aqueous solutions. Previous research by Hiroshima University has shown that a bis(triethoxysilyl)ethane (BTESE) can withstand temperatures up to 80 °C and also exhibit excellent chlorine resistance in desalination applications with no significant changes in filtration performance [ 11 , 13 ].…”

“…Hiroshima University’s successful strategy for controlling the water ratio (WR) to design the pore networks of BTESE membranes for both gas separation and reverse osmosis applications has been demonstrated through studies [ 11 , 13 , 20 ]. Additionally, there are many who conducted research on multiple generations of organoalkoxysilanes, such as bis(triethoxysilyl)methane (BTESM) and 1,3-bis(triethoxysilyl)propane (BTESP), 1,4-bis[2-(triethoxysilyl)vinyl]benzene (BTES-VB), and 2,5-bis[2-(triethoxysilyl)vinyl]pyridine (BTESVP) to tailor the pore size of organosilica membranes for gas separation (GS), pervaporation (PV), and RO applications [ 9 , 10 , 11 , 12 , 13 , 20 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ].…”

Preparation of chlorine resistant thin‐film‐composite reverse‐osmosis polyamide membranes with tri‐acyl chloride containing thioether units

“…Introducing an alkyl group between the N atom of the amide bond and the benzene ring or Cl, Br, F, COOH, SO 3 H, NO 2 strong electron withdrawing group on the benzene ring, which destroys the electron‐rich region of the resonance, and also reduce the attack of active chlorine. The large steric hindrance groups CH 3 , C 2 H 5 , OCH 3 , OC 2 H 5 are introduced at the ortho and para positions of the benzene ring connected to the amide bond to hinder the attack of active chlorine 30–33 . Physical coating, 34–36 reactive small/macro‐molecules chemical grafting 17,37–45 and nano‐materials grafting 46–49 are also effective methods to improve chlorine resistant.…”

“…The large steric hindrance groups CH 3 , C 2 H 5 , OCH 3 , OC 2 H 5 are introduced at the ortho and para positions of the benzene ring connected to the amide bond to hinder the attack of active chlorine. [30][31][32][33] Physical coating, [34][35][36] reactive small/macromolecules chemical grafting 17,[37][38][39][40][41][42][43][44][45] and nano-materials grafting [46][47][48][49] are also effective methods to improve chlorine resistant. The chlorine-resistant polymers and inert compounds as a protective layer that covers the PA layer or protective compounds by reacting with unreacted amine groups, acid chloride groups or carboxyl groups generated after hydrolysis.…”