One-pot fabrication of magnetically recoverable acid nanocatalyst, heteropolyacids/chitosan/Fe3O4, and its catalytic performance

A novel magnetic Preyssler acid grafted chitosan nano adsorbent: synthesis, characterization and adsorption activity

“…The PCNF composite was prepared according to the modified Kong et al method . In the synthesis of chitosan–Fe 3 O 4 core‐shell (CS‐Fe 3 O 4 ), 1 g of chitosan was dissolved in 100 mL of acetic acid solution (0.05 mol L −1 ), followed by the addition of 1 g Fe 3 O 4 nanoparticles.…”

Magnetic and Stable H3PW12O40‐Based Core@shell Nanomaterial towards the Esterification of Oleic Acid with Methanol

“…To obtain uniformly coated chitosan shells with good dispersion, and in continuation of our previous work on the one-pot sol-gel synthesis of Fe 3 O 4 @SiO 2 -NH 2 nanomaterials, [49,50] we have prepared magnetic nanoparticles with good dispersibility in which a high content of HPW was successfully anchored onto the cross-linked chitosan coating preformed on the superparamagnetic Fe 3 O 4 cores (designated as Fe 3 O 4 @SiO 2 -NH 2 /HPW@CS/HPW). Although there are some reports of the use of chitosan as an outer coating of magneic cores, [31,34] to the best of our known-ledge, few of them focused on the preparation of magnetic microspheres with a larger size and acting as a highly efficient support for HPW. In this article, the designed multifunctional materials exhibit large magnetization, easily accessible active acid sites, and improved catalytic performance in the esterification of oleic acid with methanol in comparison with Fe 3 O 4 @SiO 2 -NH 2 /HPW with a low HPW content due to limited anchoring sites.…”

“…Although small magnetic nanoparticles enhance catalytic efficiency through their inherently large surface area, they generally have drawbacks associated with poor dispersion, easy aggregation, non-uniform coating, as well as being unfavorable for the coating process. [30][31][32]39] Thus, rationally designed larger magnetic particles hold great promise for the development of new functional materials. [36] In addition, taking advantage of the overall negative charge of heteropolyanions by introducing electrostatic interactions between the support and HPW could strengthen their interaction and hence improve the durability of the HPW species.…”

Fe3O4@OA–Pd and Mo10V2@NSiO2 nanoparticles: an efficient and reusable catalytic system for Heck reaction under ligand free conditions

“…Fe 3 O 4 nanoparticles as a catalyst support have been attracting more and more attention because they can be easily recovered from the reaction mixture simply by using an external magnet, thus eliminating the necessity of tedious centrifugation, filtration, or membrane separation steps [11][12][13][14][15][16][17][18][19].…”