Isomerization of lactose catalyzed by alkaline-substituted sepiolites

Strong base catalysts, prepared by substituting a part of the Mg2+ located at the borders of the channels of sepiolite with alkaline ions (Li+, Na+, K+ and Cs+), were investigated as catalysts for the isomerization of lactose to lactulose and epilactose. The activities exhibited by alkaline-exchanged sepiolites were significantly higher than that of natural sepiolite. The influence of temperature, time of the reaction and catalyst loading were also evaluated. A 20% conversion was obtained at 90°C at a catalyst loading of 15 g litre-1. Copyright (C) 1999 Elsevier Science Ltd.