Catalysts Based on TiO2 for The Conversion of Ethanol to 1,3-Butadiene

• Main Authors: KAO,Yu-Zhi, 高鈺植
• Other Authors: LI,KUO-TSENG
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/w8dph3

碩士 === 東海大學 === 化學工程與材料工程學系 === 107 === This study used several TiO2-based catalysts to catalyze the conversion of ethanol to 1,3-butadiene. TiO2-ZrO2 mixed metal oxides with different Ti/Zr molar ratios were prepared by a co-precipitated method, and TiO2 exhibited the best performance. We also found that self-prepared TiO2 exhibited better performance than commercial TiO2 catalyst. The effects of additives (B2O3 and K2O) and their contents on the performance of TiO2 catalyst were investigated in a temperature range of 340℃ - 400℃ and in a catalyst weight range of 0.1g - 0.8g. Ethanol conversion was very sensitive to temperature with the use of self-prepared TiO2, the maximum butadiene yield of 9.68% (with an ethanol conversion of 40.98%) was obtained at 360℃ and 10mins time on stream. With the use of 0.1wt%B2O3/TiO2 catalyst, the maximum butadiene yield of 12.30% (with an ethanol conversion of 36.05%) was obtained under the same reaction conditions. Kinetic studies of 0.1% B2O3/TiO2 and TiO2 catalysts, indicating that ethanol conversion to 1,3-butadiene could be treated as the first order irreversible reaction, with activation energies of 52.9 kJ/mole and 71.8 kJ/mole, respectively. In order to understand the relationship between catalyst physical properties and their catalytic performances, catalysts were characterized with field emission electron microscopy (FE-SEM), energy dispersive spectrometer (EDS), X-ray powder diffraction (XRD), specific surface area and pores analyzer (BET),pyridine absorbed or CO2 absorbed–Fourier transform infrared spectroscopy (Pyridine-IR or CO2-IR), n IV butylamine absorbed-thermal gravimetric analysis (n-butylamine-TGA), inductively coupled plasma with atomic emission spectroscopy (ICP-AES). Self-prepared TiO2 catalyst exhibited larger surface area and more acid-base sites than the commercial TiO2 catalyst. The addition of B2O3 increased acid site amounts, resulted in the enhancement of catalytic performance. EDS analysis results indicated that spent TiO2 catalyst contained 12.91wt% carbon. After the regeneration process, the catalyst still had 4.04wt% carbon, indicating that regeneration process couldn’t burn off the carbon completely, resulting in the decrease of conversion and yield, compared to the fresh catalyst.