(135e) Selective Oxidation of Glycerol to High-Value Chemical Dihydroxyactone Over PtBi/C Catalyst

With increasing biodiesel production, large amounts of glycerol are obtained as byproduct, in a 1:10 ratio with biodiesel, resulting in its price decrease from 43 to 13 cents/gallon in the last three years. To maximize the economics of biodiesel production, it is essential to devise methods to utilize the byproduct glycerol. We use glycerol as feedstock for the oxidation reaction, which can produce a range of valuable fine chemicals. The most important of these oxygenates is dihydroxyacetone (DHA), valued at ~$20/lb. To-date, DHA has been used mainly as a sunless tanning agent in the cosmetics industry and as a food additive, but it also has other potential large-scale uses. Catalytic oxidation of glycerol to DHA was conducted in a semi-batch reactor (Parr) in the presence of bismuth promoted platinum catalyst, supported on activated carbon (PtBi/C). The bimetallic catalyst was optimized for synthesis conditions, Pt/Bi ratio, metal loading, structure and morphology, and support type. Various characterization techniques (BET, XRD, SEM, TEM, EDXS, XPS, etc.) were used to understand the catalyst properties that yield the best performance. Based on the obtained results, optimum process conditions (pressure, temperature, reaction time, etc) were identified to maximize the DHA yield.