Efficient production of furfural from xylose and wheat straw by bifunctional chromium phosphate catalyst in biphasic systems

We present here a study of the production of furfural from xylose and wheat straw using the chromium phosphate (CrPO4) with Lewis and Bronsted acidity as a highly efficient catalyst in the water/tetrahydrofuran (THF) biphasic system. The effects of various reaction parameters including reaction temperature, reaction time, system, and catalyst dosage were explored to evaluate the product yield. Under CrPO4 catalysis, an excellent furfural yield could reach 88% from the xylose at 160 degrees C for 60 min. Meanwhile, 67% furfural and 32% 5-hydroxymethylfurfura (HMF) were simultaneously achieved from wheat straw at 180 degrees C for 90 min. Mechanistic studies suggested that the perfect catalytic activity of CrPO4 was due to its inherent bifunctional catalysis activity. It was found that the CrPO4 was easily to be recovered and a great catalytic activity was available after four cycles, which not only contributed to a sustainably reduced energy consumption on catalyst recovery, but also reduced the concerns associated with toxic chromium element.