Research Article
Biomass Derivative Valorization Using Nano Core-Shell Magnetic Materials Based on Keggin-Heteropolyacids: Levulinic Acid Esterification Kinetic Study with N-Butanol
Figure 1
SEM images of (a) Fe3O4, (b) Fe3O4@SiO2, (c) Fe3O4@SiO2@SiO2/TPA without calcination, and (d) Fe3O4@SiO2@SiO2/TPA calcined at 673 K under nitrogen atmosphere.
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