Research Article

Biomass Derivative Valorization Using Nano Core-Shell Magnetic Materials Based on Keggin-Heteropolyacids: Levulinic Acid Esterification Kinetic Study with N-Butanol

Figure 4

XRD of the Fe3O4@SiO2 and Fe3O4@SiO2@SiO2/TPA400N2 samples.
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