Patent ID: 8816068
Filing Date: 2014-08-26
Classification: C07B,C07C,C07H

Abstract:
1. A process for catalytic hydrogenation of a sugar selected from the group consisting of lactose and xylose to the corresponding sugar alcohol, comprising subjecting the sugar to hydrogenation conditions that maintain catalyst activity during consecutive hydrogenations by limiting the content of aldonic acid selected from lactobionic acid, where lactose is the sugar, or xylonic acid, where xylose is the sugar, on the catalyst to less than 3% by wet weight of the catalyst, wherein the hydrogenation conditions comprise: introducing a sugar solution into a hydrogenation reactor at an initial temperature of 50 to 100° C., hydrogenating the sugar solution by gradual heating of the solution at a heating rate in the range of 0.2 to 1.5° C./min to a final hydrogenation temperature in the range of 100 to 140° C., wherein the difference between the initial hydrogenation temperature and the final hydrogenation temperature is in the range of 80 to 20° C., and continuing the hydrogenation at the final hydrogenation temperature until a conversion of the sugar to the sugar alcohol of more than 95% is achieved, whereby the content of lactobionic acid or xylonic acid on the catalyst is limited to less than 3% by wet weight of the catalyst.