Hydrogenation of fatty acid methyl esters to fatty alcohols at supercritical conditions
1999
Hark, Sander van den | Härröd, Magnus | Møller, Poul
Extremely rapid hydrogenation of fatty acid methyl esters (FAME) to fatty alcohols (FOH) occurs when the reaction is conducted in a substantially homogeneous supercritical phase, using propane as a solvent, over a solid catalyst. At these conditions, the limitations of hydrogen transport are eliminated. At temperatures above 240°C, complete conversion of the starting material was reached at residence times of 2 to 3 s, which is several orders of magnitude shorter than reported in the literature. Furthermore, formation of by-products, i.e., hydrocarbons, could be prevented by choosing the right process settings. Hydrogen concentration turned out to be the key parameter for achieving the above two goals. As a result of the supercritical conditions, we could control the hydrogen concentration at the catalyst surface independently of the other process parameters. When methylated rapeseed oil was used as a substrate, the hydrogenation catalyst was deactivated rapidly. However, by using methylated sunflower oil, a catalyst life similar to that obtained in industrial processes was achieved. Our results showed that the hydrogenation of FAME to FOH at supercritical conditions is a much more efficient method than any other published process.
显示更多 [+] 显示较少 [-]