Selective oxidation of propylene glycol to pyruvaldehyde

摘要

As an example of highly difficult oxidative dehydrogenation, reaction of propylene glycol to form pyruvaldehyde (methyl glyoxal) was chosen and activities of various catalysts in this reaction were compared. Iron phosphate (FePO_4) doped with a small amount of molybdenum is a unique catalyst showing a high selectivity as well as a high activity. The optimum temperature was found to be around 180 deg C. At a higher temperature, the C-C bond fission to form formaldehyde and acetaldehyde was promoted, while at a lower temperature, formation of unidentified compounds increased. It was also found that the selectivity to pyruvaldehyde increases markedly as the feed rate of steam increases. The effects of molybdenum doped into FePO_4 were discussed.