Deep-Permeation Nanocomposite Structure of ZIF-8 inside Porous Poly(tetrafluoroethylene) by Flow Synergistic Synthesis

Abstract

It is challenging to fabricate stable, complete, controllable, homogeneous metal–organic framework composites. Hereof, we suggested a versatile method where nanocrystals were assembled inside the porous polymer by synergistic chemical synthesis and permeation flow in and through its pores. The poly­(tetrafluoroethylene) (PTFE)/ZnO and PTFE/ZIF-8 were fabricated as the prototype of the composites. For fabricating the composite, ZnO was first synthesized inside the pores followed by ligand vapor treatment. The even and well-distributed ZnO nanorods of 10–30 nm were synthesized inside pores of PTFE and converted into ZIF-8. The ZnO and ZIF-8 were quantified in 281 and 431 mg g–1 against the original PTFE, respectively. The composite is stable and the nanocrystals are not readily washed away. The adsorption uptake (C3 > C2 > C1) of the light hydrocarbon gases for the PTFE/ZIF-8 nanocomposite were preliminarily evaluated. The adsorption selectivities were calculated, where the selectivities for C2H6/CH4 and C3H8/CH4 were 10.9 and 42.8, respectively.

Catalytic Membrane Reactor of Nano (Ag+ZIF-8)@Poly(tetrafluoroethylene) Built by Deep-Permeation Synthesis Fabrication

“…All the reagents used in the experiments were analytical grade and utilized without further purification. The synthesis equipment used for preparing the DPNS was reported in our previous work …”

“…With small particle size and uniform distribution, the composite (socalled the deep-permeation nanostructure, DPNS) showed good stability and adsorption performance. 27 We believed that this composite structure could provide an idea to form a new CMR. Therefore, based on our previous works on the design and application of DPNS, we have introduced a hierarchical composite to be a CMR.…”

“…In our previous work, ZIF-8 NPs were successfully synthesized in situ inside the membrane pores through the deep-permeation synthesis fabrication (DPSF) method. With small particle size and uniform distribution, the composite (so-called the deep-permeation nanostructure, DPNS) showed good stability and adsorption performance . We believed that this composite structure could provide an idea to form a new CMR.…”

Isolated iron/polyether sulfone catalytic membranes for rapid phenol removal

“…19 Additional benefits include (1) avoiding the need to disperse the catalyst and separate it from the reaction mixture, 20 (2) enhancing the conversions of thermodynamically limited reactions by in-situ product removal, (3) increasing selectivity for consecutive reactions by removing intermediate products, 21 (4) long-term use and continuous catalysis without additional catalyst recycling. 22 For a common type of CMR, the catalyst can be distributed as a thin layer attached to the matrix membrane surface or in the pore of the matrix membrane with high dispersity. 23 Vital et al 24 and Hilmioglu et al 25 incorporated sulfonic acid group in polyvinyl alcohol (PVA) matrix and chitosan membranes by crosslinking and blending method respectively, and achieved enhanced catalytic activity for esterification and pervaporation reaction.…”

“…CMR offers many advantages, including small footprint, reduced equipment cost, low energy consumption, and high efficiency 19 . Additional benefits include (1) avoiding the need to disperse the catalyst and separate it from the reaction mixture, 20 (2) enhancing the conversions of thermodynamically limited reactions by in‐situ product removal, (3) increasing selectivity for consecutive reactions by removing intermediate products, 21 (4) long‐term use and continuous catalysis without additional catalyst recycling 22 . For a common type of CMR, the catalyst can be distributed as a thin layer attached to the matrix membrane surface or in the pore of the matrix membrane with high dispersity 23 .…”