Ultrathin Water-Cast Polymer Membranes for Hydrogen Purification

Abstract

Among various H2 purification technologies, the use of membrane technology has been considered an ecofriendly approach for addressing the increasing hydrogen demand. Although many H2-selective membrane materials have been reported, processing them into hollow fibers or thin-film composites (TFCs) via traditional methods either affects the performance of the materials or renders their further processing into applicable membrane forms infeasible. Herein, we propose a water-casting method for fabricating TFC membranes for hydrogen purification with high permselectivity. The film integrity and thickness were manipulated by controlling the spreadability of the casting solution, and the resultant water-cast TFC membrane that comprised an ∼30 nm selective layer demonstrated high H2 permeance and H2/CH4 selectivity of approximately 190 GPU and 100, respectively, under optimized conditions. We performed a mixed-gas permeation test using a simulated off-gas of steam–methane reforming from natural gas in a single-stage system and obtained hydrogen gas of >99 mol % purity. This indicates not only the suitability of the water-cast membranes for satisfying the demand for pure hydrogen as a fuel and chemical reagent but also the great potential of the water-casting method for high-performance membranes in various industrial and environmental applications.

Preparation of freestanding and ultrastable CsPbX3 perovskite quantum dots/SEBS composite films for curved and flexible surfaces

“…48 Different solvent and polymer contents in solution can vary the S of the liquid, and have an influence on the size and thickness of the films prepared. 49 For example, the calculated S of CsPbBr 3 PQDs/ SEBS/cyclohexane dispersion (0.15 g ml À1 , on the aqueous surface) was 15.5 mN m À1 (ESI †), indicating the spreading ability of the droplet. With a moderate spreading coefficient and volatility, CsPbX 3 PQDs/SEBS composite films without any pinhole or defect were formed at the air-water interface.…”

Footsteps of graphene filled polymer nanocomposites towards efficient membranes—Present and future

“…Polymer-and graphene-derived nanocomposite membranes have been efficiently used for the separation of hazardous molecules [8]. For the fabrication of polymer/graphene membranes, facile processing approaches have been used [9]. Solution processing, the phase inversion method, the infiltration technique, and other facile methods have been reported [10,11].…”

Graphene in gas separation membranes—State-of-the-art and potential spoors

“…Efficient and facile processing technologies have been applied such as solution casting, doctors blading technique, in situ method, phase inversion, infiltration, lift-off/float-on, etching, etc. have been applied [18,19]. Mostly, thermoplastic matrices have been examined to form the graphene derived nanocomposites and membranes for gas separation [20][21][22].…”