Wells–Dawson heteropoly acid encapsulated into the nanocages of SBA-16 as heterogeneous catalyst for the oxidation of olefins and alcohols

Abstract

Wells-Dawson type 18-tungstophosphoric acid (H 6 P 2 W 18 O 62 ) as guest was encapsulated inside the nanocages of mesoporous SBA-16 host. The pore entrance of SBA-16 material was modified by silylating reagent to prevent the escape of encapsulated H 6 P 2 W 18 O 62 from the nanocages. The prepared host-guest material was characterized by different physicochemical techniques. X-ray diffraction and transmission electron microscopy analyses indicated the retention of mesoporous structure of SBA-16 and well-dispersion of the H 6 P 2 W 18 O 62 into the nanocages of SBA-16. The obtained material exhibited high catalytic activity, stability, and recyclability in the epoxidation of olefins and oxidation of alcohols in the presence of H 2 O 2 as oxidant.

Encapsulation of Keggin-type phosphotungstic acid into the mesopores of SBA-16 as a reusable heterogeneous catalyst for the epoxidation of olefins

“…Comparison of these results with our recently published work on the catalyst derived from the immobilization of H 6 P 2 W 18 O 62 compound with WellsDawson structure into the SBA-16 [53], shows that the Keggin-type structure, i.e. PTA@SBA-16, has compa- rable (e.g., in the case of cyclooctene and cyclohexene) or even higher (e.g., in the case of 1-octene and 1-hexene) activities in the epoxidation of ole ns.…”

“…It has a three-dimensional cubic mesoporous structure and, due to its large nanocages, it is a promising support for the encapsulation of POMs. While the immobilization of POMs catalysts on mesoporous materials such as SBA-15 and MCM-41 has been widely reported [31,44], to the best of our knowledge, there are few reports devoted to the immobilization of POMs into the mesoporous SBA-16 without investigating its catalytic activity and stability [37,53,54].…”

Magnetic, Biocompatible and Biodegradable Carboxymethyl Cellulose‐Based Hydrogel for Cationic Dye Adsorption

“…In MNH, the observed peak at a wavenumber of 3440 cm −1 is related to the stretching vibration of the OH group in the hydrogel network. The observed peak at wavenumbers 2924, 2962, and 2857 cm −1 represent the aliphatic C−H in the structure of hydrogel [39] . The peak shown at a wavenumber of 1626 cm −1 is related to the stretching of the carbonyl group.…”

“…The observed peak at wavenumbers 2924, 2962, and 2857 cm À 1 represent the aliphatic CÀ H in the structure of hydrogel. [39] The peak shown at a wavenumber of 1626 cm À 1 is related to the stretching of the carbonyl group. Bending vibrations of CH 2 is demonstrated by the peak at 1404 cm À 1 .…”

Lignosulfonate-Coated ZIF-8 as an Effective Nanofiller to Prepare High-Performance Thin-Film Nanocomposite Forward Osmosis Membrane for Heavy Metal Ions Removal

“…MOFs, as a type of hybrid organic–inorganic porous crystalline nanostructure, are constructed by assembling organic linkers and metal ions by strong coordinate covalent bonds. A variety of MOFs are constructed by manipulating their chemical compositions, morphologies, and sizes to meet different unique applications. , However, preparation of the hydrophilic MOFs-modified TFN-FO membrane for water purification is difficult. This is mostly related to the hydrophobicity of the MOFs, which negatively impacts the total efficiency of such TFN-FO membranes, such as their water permeation and antifouling tendency.…”