Dehydration of xylose to furfural using a Lewis or Bronsted acid catalyst and N2 stripping

The activity of Lewis (Nb2O5) and Bronsted (Amberlyst 70) acid catalysts for the cyclodehydration of xylose to furfural was studied. The nature of the acidity resulted in significant changes in the reaction mechanism. Lewis acid sites promote the formation of xylulose, while Bronsted acid sites are required to further dehydrate the sugar to furfural. Amberlyst 70 in water/toluene at 175 degrees C showed lower activity but gave a higher furfural yield. Using N-2 as the stripping agent considerably improved the furfural yield and product purity in the stripped stream. Catalyst stability was also studied. (C) 2013, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.