Abstract
In this study, Keggin- and Dawson-type polyoxometalates (POMs) were immobilized on chitosan (CS)-modified Fe3O4@CS by electrostatic interaction for the preparation of heterogeneous catalysts Fe3O4@CS@POM (POM=PMo12, PW12, SiW12, P2W17, or P2W18). The oxidative desulfurization (ODS) of dibenzothiophene (DBT) by Fe3O4@CS@POMs was evaluated. It is found that Fe3O4@CS@POM shows the good ODS performance due to the good dispersion of POM on Fe3O4 surface and the good accessibility of substrate to it leaded by the full swelling of the cross-linked CS in acetonitrile. The catalytic activity follows the order of Fe3O4@CS@PMo12 > Fe3O4@CS@PW12 > Fe3O4@CS@P2W17 > Fe3O4@CS@P2W18 > Fe3O4@CS@SiW12. At 333 K, the desulfurization rate of DBT (500 ppm) reaches 99.7% at 60 min and 100% at 90 min in the presence of 0.1 g of Fe3O4@CS@PMo12 and 100 µL of H2O2. The ODS process can be well described by the pseudo-first-order kinetic model (R2 > 0.99) with a high kinetic constant (0.0761 min−1) and a low apparent activation energy (60.57 kJ / mol). In addition, the as-prepared catalyst can be easily separated and recycled in the external magnetic field, and it still has the good reusability for several times, stemming from the stable encapsulation of POM clusters by cross-linked chitosan on Fe3O4 surface.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of the Taiwan Institute of Chemical Engineers
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
