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

With the PTFE membrane as the substrate, a novel Ag-based catalytic membrane reactor (CMR) was fabricated by deep-permeation synthesis fabrication (DPSF). In DPSF, ZIF-8 was first assembled inside the membrane pores by permeation flow and the depositing reaction of Zn2+, and 2-methylimidazole solutions flow through the membrane synergistically. Then, Ag was reduced inside the pores impregnating ZIF-8 nanoclusters by Ag+ and reductant solutions flowing through the membrane similarly. The TEM images of the cross-sectional membrane exhibited the composite nanoparticles of Ag+ZIF-8 with good dispersion and size distribution (10-50 nm). The as-synthesized (Ag+ZIF-8)@PTFE was applied to the catalytic reduction of p-nitroaniline to p-phenylenediamine in a continuous flow-through reactor and presented remarkable catalyzing performance. The maximal apparent reaction rate constant is 3-4 orders of magnitude higher than that reported with good stability.