Perillyl alcohol preparation from β-pinene oxide using Fe-modified zeolite beta

Abstract

Iron-modified zeolites beta with different loading of iron (0–10 wt.% of iron) were used for the preparation of perillyl alcohol from β-pinene oxide. The prepared catalysts were characterized by XRD, XRF, UV/Vis and TPD of pyridine to determine their structural properties and acidity. The influence of iron loading, solvent type (DMSO and DMF) and presence of strong Bronsted acid (nitric acid) on the reaction course was evaluated. The highest selectivity to perillyl alcohol was obtained using catalyst with 1.25 wt.% of iron. This catalyst was not the most acidic, but the interaction of iron sites in the catalyst with strong basic polar solvent was supposed to influence positively the conversion. With an increasing amount of iron in zeolite beta, the selectivity together with conversion decreased. The type of the solvent was the most important parameter in the studied reaction—using DMSO, a significantly higher conversion in the same time and selectivity was observed compared to the reaction using DMF. The presence of nitric acid in the reaction mixture positively influenced both conversion and selectivity. The synergy between iron-modified zeolite beta, nitric acid and DMSO led to high selectivity (up to 65%) to perillyl alcohol. No iron leaching was observed during the reaction.