A magnetic catalyst based on immobilization of dysprosium ions on the surface of CoFe 2 O 4 nanoparticles has been reported and used as an efficient magnetic nanocatalyst for the selective oxidation of organic sulfides and synthesis of symmetrical disulfides containing aromatic and aliphatic sulfides and thiols. The magnetic solid catalyst has been identified using TGA, FT-IR, VSM, ICP, SEM, and XRD. Moreover, the cat- alyst can also be separated with an external magnet and recycled several times without any remarkable decrease in its catalyst activity.
