Catalysis Preparation of Biodiesel from Waste Seed Oil with the Ionic Liquid Immobilized in a Magnetic Catalyst: FeO@SiO@[C4mim]HSO.

The purpose of this study was to synthesize a magnetic material that could be easily separated by a magnetic field and combined the catalytic function of an acid/base ionic liquid with silicon for biodiesel preparation. A kind of magnetic catalyst-immobilized ionic liquid was synthesized by a three-step method. The synthesis conditions in each step were optimized by single-factor analysis.