Multilayer thin-film composite membranes for helium enrichment

Gas separation and water desalination performance of defect-free interfacially polymerized para-linked polyamide thin-film composite membranes

“…The first reports of 'caulked' IPderived TFCs were based on rubbery polyether-polyamide block copolymer (Pebax®) coatings on commercial seawater and brackish water membranes, which demonstrated excellent selectivity for H 2 /CO 2 and H 2 /CH 4 applications [32,33]. Alternative sealing layer materials, such as Nafion® 117 [37,38], poly(phenylene oxides) [38] and polydimethylsiloxane [39], were later applied to render commercial RO and NF membranes potentially suitable for gas separation applications. However, simply applying a caulking approach to commercial RO or NF membranes limits the systematic optimization of their transport properties for gas separation applications as the proprietary chemistry and membrane formation protocols are not fully known.…”

A generalized numerical framework for solving cocurrent and counter-current membrane models for gas separation

“…In air separation, it is used for nitrogen production [ 5 ]. It is also used for biogas purification [ 6 ] as well as in the water/wastewater treatment [ 7 , 8 , 9 ], food [ 10 ], and pharmaceutical industries [ 11 ]. Compared to the typical separation techniques, including cryogenic distillation, absorption, and adsorption methods, membrane technology shows higher simplicity, lower cost, moderate operating conditions, and favorable environmental features [ 12 , 13 ].…”

“…The fibers are polymeric, inorganic-based, or mixed matrices with different lengths, internal diameters, and thicknesses in the ranges of 0.15–2 m, 63–389 μm, and 32.5–173 μm, respectively [ 14 , 15 , 16 ]. The performance of the membrane modules is a function of flow patterns, fiber properties, fiber configuration and operating conditions [ 6 , 16 ].…”

“…Stage-cut is defined as the ratio of permeate to feed flow and varies in the range of 0.01–0.87 by changing the feed flow rate for a constant-length membrane [ 3 , 6 ].…”