Chemical hydrolysis of cellulose into fermentable sugars through ionic liquids and antisolvent pretreatments using heterogeneous catalysts

We studied the use of heterogeneous catalysts with sulfonic groups in the hydrolysis of cellulose. The treatment based on dissolution/precipitation in ionic liquids yields a clear enhancement in the conversion of cellulose and glucose formation with heterogeneous catalysts. The activity results indicated that there is a relation between the acidity of the catalyst and its activity in the hydrolysis of cellulose. However, the nature of the surface groups on the catalysts seems to have a dramatic effect on the activity. The presence of hydroxyl groups (-OH) and Si-0 Si bonds at the surface of silica-based catalysts could favor the adsorption of cellulose chains and enhance the activity of the catalysts. This study showed that the hydrolysis of cellulose treated with dissolution/precipitation using an ionic liquid produces a glucose yield of approximately 50% at 140 C in just 5 h. These results are a promising starting point for further studies.