title: Synthesis of sulfonic acid-functionalized Fe3O4@C nanoparticles as magnetically recyclable solid acid catalysts for acetalization reaction.
abstract: The Fe3O4@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 Fe3O4@C magnetic nanoparticles were obtained by grafting the sulfonic groups on the surface of Fe3O4@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.
authors.affiliation: Hefei National Laboratory for Physical Science at Microscale and Department of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026, P. R. China. cqw@ustc.edu.cn.
authors.forename: Fang-Cai
authors.initials: FC
authors.lastname: Zheng
authors.forename: Qian-Wang
authors.initials: QW
authors.lastname: Chen
authors.forename: Lin
authors.initials: L
authors.lastname: Hu
authors.forename: Nan
authors.initials: N
authors.lastname: Yan
authors.forename: Xiang-Kai
authors.initials: XK
authors.lastname: Kong