Thesis (M.Eng.)--Chulalongkorn University, 2012

In this research, the effects of operating conditions on the hydrogenation of isomaltulose were evaluated. The reaction was catalyzed with Ru/C catalysts prepared from the impregnation of Ruthenium on activated charcoal powder. The catalysts were characterized by N2 physisorption, XRD and XRF techniques. The reactions were carried out in a pressure vessel stirring reactor, with isomaltulose (40 wt% in DI water) where the impeller speed was maintained at a maximum speed of 670 rpm. The Ru/C catalyst was calcined in argon at 500°C for 4 h, and reduced at 200°C under flowing H2 for 2 h. The hydrogenation of isomaltulose was successfully performed with 10% Ru/C catalysts. The rate of reaction increased with increasing weight ratio of catalyst/reactants at the reaction temperature of 130 °C and 50 bar. The reaction rate followed the first order dependency with respect to hydrogen. The kinetics fitted best with Langmuir-Hinshelwood-Hougen-Watson (LHHW). The observed activation energy confirmed that the reaction was under chemical control. The Ru/C catalyst seemed to be relatively stable as it still provided a complete hydrogenation of isomaltulose even after reusing in three consecutive batches