Magnetic composites Fe3O4@SiO2@PILs as sorbents for efficient denitrogenation of fuel oil

In this work, the study of synthesis and denitrogenation of magnetic polymeric ionic liquids (PILs) for N-compounds in simulated oils and diesel are reported. Three functionalised magnetic particles, Fe 3 O 4 @SiO 2 @PILs with side alkyl chain of C2, C4 and C6, respectively, were prepared by grafting PILs on the surface of silica-coated Fe 3 O 4 . Fourier transform infrared spectra, thermogravimetric analysis, X-ray diffraction and scanning electron microscopy were carried out to characterise the structure of Fe 3 O 4 @SiO 2 @PILs. It has shown that Fe 3 O 4 @SiO 2 @ PILs possess precious merits for sorbents, such as regular morphology, good stability and magnetic properties. Denitrogenation experiments of simulated oils demonstrate that Fe 3 O 4 @SiO 2 @ PILs show better denitrogenation efficiency of basic N-compounds than neutral N-compounds. The effects of temperature, reaction times, ratio of reagent to oil on denitrogenation for simulated oils were explored, and 92.1% denitrogenation efficiency was obtained to remove quinoline from simulated oils. Denitrogenation of Fe 3 O 4 @SiO 2 @PILs in diesel leads to 84.3% denitrogenation efficiency, and it can remain 82.5% denitrogenation efficiency after five times of recycles. Compared with other similar sorbents, Fe 3 O 4 @SiO 2 @PILs show competitive performances to eliminate organic N-compounds. It is hopeful that Fe 3 O 4 @SiO 2 @PILs can be promising sorbents for purification of liquid fuel by adsorptive denitrogenation.