Synthesis of sulfonic acid-functionalized Fe3O4@C nanoparticles as magnetically recyclable solid acid catalysts for
Fang-Cai Zheng1, Qian-Wang Chen, Lin Hu
1Hefei 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.
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.
