Synthesis of sulfonic acid-functionalized Fe3O4@C nanoparticles as magnetically recyclable solid acid catalysts for acetalization reactionElectronic supplementary information (ESI) available. See DOI: 10.1039/c3dt52098f

• Main Authors: Zheng, Fang-Cai, Chen, Qian-Wang, Hu, Lin, Yan, Nan, Kong, Xiang-Kai
• Format: Journal Article
• Language: English
• Published: 10.12.2013
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c3dt52098f

The Fe 3 O 4 @C core-shell magnetic nanoparticles with an average size of about 190 nm were synthesized via a one-pot solvothermal process using ferrocene as a single reactant. The sulfonic acid-functionalized Fe 3 O 4 @C magnetic nanoparticles were obtained by grafting the sulfonic groups on the surface of Fe 3 O 4 @C nanoparticles to produce magnetically recyclable solid acid catalysts. The as-prepared products were characterized by X-ray diffraction and transmission electron microscopy. The catalytic performance of the as-prepared catalysts was examined through the condensation reaction of benzaldehyde and ethylene glycol. The results showed that the catalysts exhibited high catalytic activity with a conversion rate of 88.3% under mild conditions. Furthermore, catalysts with a magnetization saturation of 53.5 emu g −1 at room temperature were easily separated from the reaction mixture by using a 0.2 T permanent magnet and were reused 8 times without any significant decrease in catalytic activity. In this article, we report a route for preparing highly efficient, stable, and magnetically recyclable solid acid catalysts via grafting sulfonic groups on the surface of Fe 3 O 4 @C MNPs, showing a high efficiency in the acetalization reaction of benzaldehyde with ethylene glycol.