摘要:
A continuous process for converting carbohydrates to ethylene and propylene glycol. The carbohydrates are mixed with water and passed through a reactor at a temperature that hydrolyzes the carbohydrate mixture at least partially to monosaccharides. The reactor has a first zone comprising a retro-aldol catalyst and a second zone comprising a reducing catalyst. The aldose is converted in the first zone into glycolaldehyde by the retro-aldol catalyst and the glycolaldehyde, in the presence of hydrogen, is converted to ethylene glycol in the second zone of the reactor. The reaction products are removed from the reactor and the ethylene glycol is recovered. The selectivity to propylene glycol can be enhanced via feeding ketose as the carbohydrate.