Hydrothermolysis of carbohydrates to levulinic acid using metal supported on porous aluminosilicate
Correspondence to: Duangamol Nuntasri Tungasmita, Materials Chemistry and Catalysis Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand. E-mail: email@example.com
Aluminosilicate catalysts have the potential to promote the formation of oxygenated derivatives from carbohydrates in a hydrothermolysis reaction. Levulinic acid (LA) can be obtained from glucose, sucrose and starch hydrothermolysis reactions, and is a very versatile building block for diverse organic synthetic compounds. In this work, the catalytic performance of Ni- or Ru-doped aluminum-loaded SBA-15 (Al-SBA-15) was compared with ZSM-5 catalyst in order to achieve high LA selectivity.
All catalytic hydrothermolysis reactions tested gave remarkably higher LA selectivity than non-catalytic reactions for every carbohydrate substrate used. The acid contents and porous properties are important keys to control yield and selectivity of LA. The highest selectivity of LA (44%) was attained from glucose hydrothermolysis at 200 °C (for 1 h) using a 15 wt% loading of the 20 wt% Ru-doped ZSM-5 catalyst.
Moderately raising Ru in ZSM-5 and Al-SBA-15 catalysts increased the levels of LA. The MFI structure of ZSM-5 is suitable for hydrothermolysis of glucose monosaccharide, while the hexagonal mesoporous structure of Al-SBA-15 is preferred for starch polysaccharide hydrothermolysis at the optimum condition. © 2012 Society of Chemical Industry