Fabrication and application of silicalite-1 and TS-1 hollow fibers with polyethylene imine (PEI) fibers as substrates

Silicalite-1 and titanium containing silicalite-1 (TS-1) hollow fibers were fabricated with polyethylene imine (PEI) fibers as substrates. The acid treated PEI fibers were positively charged and can be effectively coated with silicalite-1 or TS-1 nanocrystals from their colloidal solution. The adsorbed silicalite-1 or TS-1 nanocrystals grew up and became more compact upon two days of vapor phase Ostwald ripening in autoclave. Silicalite-1 and TS-1 hollow fibers were obtained after calcination at 400 °C in air. The shell thickness of the hollow fibers is ∼1 μm. Hydroxylation of phenol with H2O2 was investigated over TS-1 based catalysts in order to compare influences of nanocrystals composed macrostructure and Al2O3 binder on the catalytic activities.

Graphical abstractPEI fibers were positively charged by pretreating with HCl solution, and then coated with the negatively charged zeolite, followed by further Ostwald ripening. Hollow fibrous structure was obtained by calcination.Figure optionsDownload full-size imageDownload as PowerPoint slide