摘要 |
<p>A method for producing L-sugars including L-idose and L-gulose as well ad D-fructose from D-glucose. The method comprises epimerizing D-glucose to a mixture of D-glucose and D-mannose, hydrogenating the mixture in a fixed catalyst bed to provide D-sorbitol and D-mannitol, separating the D-mannitol by fractional crystallization, oxidizing separately the D-sorbitol and D-mannitol to provide L-sorbose and D-fructose, respectively; and racemizing the L-sorbose in a weak alkaline solution to provide a mixture of L-sorbose, L-idose and L-gulose, and precipitating the remaining L-sorbose with a dilute lime solution. The unconverted L-sorbose is recovered and recycled.</p> |