Synthesis of Graphene Oxide Membrane for Separation of p‐Xylene and o‐Xylene by Pervaporation

Abstract

Dedicated to Prof. Dr. rer. nat. Ju ¨rgen Caro on the occasion of his 70th birthdayIn this study, a graphene oxide (GO) membrane is developed for the separation of p-xylene (PX, 0.58 nm) from o-xylene (OX, 0.68 nm). Attributing to the suitable d-spacing size (0.58 nm), the GO membrane allows more PX to pass through than OX, leading to a high PX/OX selectivity. At 110 °C for the separation of equimolar PX/OX mixture, the PX/OX separation factor is 9.4 and PX flux is 145.3 g m -2 h -1 , respectively, which is promising for the separation of xylene isomers by pervaporation. The separation performance of the GO membrane is further confirmed by simulation studies.

Exceptionally Fast Separation of Xylene Isomers with Zeolitic Nanotube Array Membranes

“…Besides, the filtration temperature was labeled by different colors in Figure 4. It is noteworthy that a very high temperature was usually needed for most separation processes to accelerate filtrate diffusion, especially those involving 13,20,21,26,27,30−39; the graphene oxide (GO), 17 carbon molecular sieve (CMS), 15 and metal−organic framework (MOF) membranes 16 are marked by circles. The filled color of each symbol denotes the filtration temperature (blue: <350 K, yellow: 350−400 K, red: >400 K).…”

“…Our simulation results are marked as stars. The data of typical membranes reported in the literature are shown for comparison: MFI-type zeolite membranes are marked by triangles and reported in refs ,,,,,− ; the graphene oxide (GO), carbon molecular sieve (CMS), and metal–organic framework (MOF) membranes are marked by circles. The filled color of each symbol denotes the filtration temperature (blue: <350 K, yellow: 350–400 K, red: >400 K).…”

“…40 Other experimental methods, such as the in situ growth method used for anodic titanium oxide nanotube array membranes, 41 and the template method used for nanoporous poly(lactide), 42 should also be applicable for the synthesis of ZNT arrays. The remaining key challenge for the fabrication of ZNT membranes is the encapsulation of the ZNT arrays with 17 carbon molecular sieve (CMS), 15 and metal−organic framework (MOF) membranes 16 are marked by circles. The filled color of each symbol denotes the filtration temperature (blue: <350 K, yellow: 350−400 K, red: >400 K).…”

“…Membrane-based separations are emerging as a potential alternative to profoundly reduce the energy consumption of xylene isomer separation. − Among all available membrane materials, MFI-type zeolites stand out as a competitive candidate owing to their uniform pore size, selective adsorption characteristics, as well as high thermal, chemical, and mechanical stabilities . Moreover, the Si/Al ratio or crystal orientation can be customized to enhance the separation selectivity. , From a structural perspective, these membranes are generally synthesized in multilayered lamella form, with the feed introduced on one side and the desired permeate filtrated on the other (Figure a).…”

Discrimination of Xylene Isomers by Precisely Tuning the Interlayer Spacing of Reduced Graphene Oxide Membrane

“…Thanks to their tunable interlayer spacing, strong organic solvent resistance, high mechanical strength, and large-scale production with low cost, 22,23 GO-based membranes have been widely employed in many separation applications, such as organic solvent nanofiltration (OSN), 24−27 gas separation 28,29 and pervaporation. 30,31 In particular, the interlayer spacing of GO-based membranes could be finely tuned to modulate the precise ion and molecule sieving properties. [23][24][25][26]32,33 Despite the intensive studies on GO-based membranes, the current research is generally limited to ion sieving in aqueous solution.…”