Conversion of cellulose to lactic acid by using ZrO2–Al2O3 catalysts

Abstract

Lactic acid has a wide range of applications in many industries, both as an ingredient and as an intermediate. Here, we investigated the catalytic conversion of cellulose to lactic acid by using heterogeneous mixed-oxide catalysts containing ZrO2. Although pure ZrO2 has catalytic activity for the conversion of cellulose to lactic acid, the yield of lactic acid obtained is not satisfactory. In contrast, a series of ZrO2 –Al2 O3 catalysts containing various percentages of ZrO2 provided higher yields of lactic acid. The ZrO2 –Al2 O3 catalysts had more Lewis acid sites and far fewer base sites than ZrO2. This suggests that the Lewis acid sites on ZrO2 –Al2 O3 catalysts are more important than the base sites for the conversion of cellulose to lactic acid.