(478a) Kinetics of Glycerol Oxidation Over Pt-Bi/C Catalyst

Identifying new uses for glycerol, a waste of biodiesel production from transesterification of vegetable oils, is of great current interest. Towards this end, catalytic oxidation of glycerol is a promising approach. The challenge, however, is the relatively complex oxidation reaction network. This work is focused on maximizing the yield of a specific oxidation product, high-value chemical dihydroxyacetone (DHA). The kinetics of glycerol selective oxidation to DHA were investigated in the presence of the Pt-Bi/C catalyst optimized previously in our laboratory, along with a microkinetic model developed based on a proposed mechanism. The experimental data from a semi-batch reactor, collected over a wide range of process conditions, including temperature, pressure and concentration, were fitted to the kinetic model to obtain the kinetic parameters (pre-exponential factor and activation energy) for each step in the network. The model was then tested by conducting additional experiments not utilized in the fitting procedure. The kinetic parameters are required to develop a fixed-bed reactor model, which could be used to determine the optimal reactor size and operating conditions (temperature, pressure, concentration and glycerol/oxygen flow rates) to maximize DHA yield.