Catalytic Fast Pyrolysis of Cellulose for the Selective Production of Levoglucosenone Using Phosphorus Molybdenum Tin Mixed Metal Oxides

Abstract

Cellulose can be selectively converted into levoglucosenone (LGO), a high-value anhydrosugar, through fast pyrolysis with acidic catalysts. Herein, phosphorus molybdenum tin mixed metal oxides (P-Mo/SnO2) were prepared for the selective production of LGO from the in situ catalytic fast pyrolysis (CFP) of cellulose, where the PO43–, P-support, and Mo6+ species in P-Mo/SnO2 played the determining role in promoting depolymerization, dehydration, and deoxygenation reactions. Pyrolysis-chromatography/mass spectrometry (Py-GC/MS) tests were carried out to explore the influence of catalyst-to-cellulose (CA-to-CL) ratio, phosphomolybdic acid (PMA) loading, and pyrolytic reaction temperature on LGO preparation. The results demonstrated the maximal LGO yield could reach 17.98 wt % via using P-Mo/SnO2 with the PMA loading of 50 wt % at the pyrolysis temperature of 300 °C and the CA-to-CL ratio of 1:1. Moreover, the highest LGO yield could be up to 12.70 wt % in lab-scale CFP tests at 300 °C and the CA-to-CL ratio of 2:1, and the LGO yield could remain above 10 wt % after five runs of catalyst calcination regeneration.