Abstract :
Ethyl levulinate (EL) is a versatile bio-based chemical with various applications such as fragrance and flavoring agents and also fuel blending component. EL can be produced through catalytic esterification of levulinic acid (LA) with ethanol. Herein, a series of zirconia (ZrO2)-supported phosphotungstic acid (HPW) (HPW/Zr) catalyst, 15-HPW/Zr, 20-HPW/Zr, and 25-HPW/Zr, were prepared, characterized, and tested for EL production. The physicochemical properties ofcatalysts were characterized using Fourier-transformed infrared (FTIR) spectroscopy, x-ray diffraction (XRD), field emission scanning electron microscope (FESEM), N2 physisorption, and ammonia temperature-programmed desorption (NH3-TPD). The effect of reaction parameters: reaction time, temperature, catalyst loading, and molar ratio of LA to ethanol was inspected on LA conversion and EL yield. The catalyst with high surface area and high acidity seemed suitable for EL production. Among the catalysts tested, 20-HPW/Zr exhibited the highest EL yield of 97.3% at the following conditions: 150 °C, 3 h, 1.0 g of 20-HPW/Zr and 1:17Mratio of LA to ethanol. The 20-HPW/Zr could be reused for at least four times with insignificant decrease in the EL yield. This study demonstrates the potential of ZrO2-supported HPWfor bio-based alkyl levulinate production at mild process conditions.
- Nur Aainaa Syahirah Ramli, Dorairaaj Sivasubramaniam and Nor Aishah Saidina Amin (2017). Esterification of levulinic acid using ZrO2-supported Phospotungstic acid catalyst for ethyl levulinate production. BioEnergy Research, 1-12. DOI: https://doi.org/10.1007/s12155-017-9872-1
