Synthesis of Eugenol Ethyl Ether by Ethylation of Eugenol with Diethyl Carbonate over KF/γ-Al2O3 Catalyst

A KF/γ-Al2O3 solid base catalyst was prepared by wet impregnation and applied to the synthesis of eugenol ethyl ether (EEE) from eugenol and diethyl carbonate. By measuring the yield of eugenol ethyl ether, we investigated the effects of the catalyst active component, impregnation temperature, KF impregnation concentration, impregnation time, and calcination temperature on catalyst performance. The results showed that the KF/γ-Al2O3 catalyst can adequately facilitate the conversion of eugenol to EEE. The characterizations of the catalysts were examined by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The characterizations of EEE were examined by nuclear magnetic resonance spectrometry (H1-NMR), gas chromatography–mass spectrometer (GC-MS) and Fourier-transform infrared spectroscopy (FT-IR). It was found that the KF/Al2O3 catalyst (impregnation temperature 60 °C, KF impregnation concentration 40%, impregnation time 8 h, and calcination temperature 450 °C) showed the best effect. The yield of EEE remained 51.2% after recycling the supported catalyst three times.