An Evaluation of Glycerol Acetalization with Benzaldehyde over a Ferromagnetic Heteropolyacid Catalyst

Tungstophosphoric acid (H3PW12O40) supported on silica-coated magnetite nanoparticles has been prepared and used as a heterogeneous catalyst (Fe3O4@SiO2@HPW) in the condensation of benzaldehyde (B) with glycerol (Gly) for production cyclic acetals. Physicochemical techniques, including scanning electron microscopy (SEM), transmission (TEM), Fourier-transform infrared spectrometry (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), N2 physisorption were to characterize catalyst. The effect glycerol/benzaldehyde molar ratio (1/1 1/1.2), temperature (80–120 °C), amount (1–5%) conversion selectivity main reaction products: benzoic acid, 2-phenyl-1,3-dioxolan-4-yl)methanol, 2-Phenyl-1,3-dioxan-5-ol, 2-phenyl-1,3-dioxolane, methyl 2-hydroxy-3-phenylpropanoate was studied evaluate catalytic activity Fe3O4@SiO2@HPW optimization these process parameters conducted using Box–Behnken design (BBD). Using BBD methodology, optimal (120 °C, 1:1.15 glycerol: benzaldehyde, 5% catalyst) determined, acetals yield 85.95% 78.36%, respectively. also exhibits excellent acetalization other aromatic aldehydes such cinnamaldehyde, p-methyl-benzaldehyde, p-hydroxy-benzaldehyde, vanillin.