High yield production of levoglucosan via catalytic pyrolysis of cellulose at low temperature

Pyrolytic sugars are fascinating feedstocks for bio-refinery, and it is of high interest to develop renewable catalysts for biomass pyrolysis. In this study, catalytic pyrolysis of cellulose to levoglucosan (LG) in improved yields was achieved with acid-base bifunctional magnetic Zn-Fe-C catalysts. Among tested catalysts, Zn-4@Fe-C-500 could not only increase LG yield by 5.4 times compared with non-catalytic cellulose pyrolysis at 300 C, but also help lower reaction temperature by 200 C due to acid-base site synergistic effect. Furthermore, the LG yield (80.1 wt %) from catalytic cellulose pyrolysis at 300 C was much higher than that commonly conducted at 500 C without catalyst (60.1 wt%). Thermogravimetric and kinetic analysis disclosed LG formation mechanism. Importantly, Zn4@Fe-C500 catalyst was highly recyclable with little deactivation after 5 consecutive cycles. This study exhibited great potential for industrial LG production from cellulose at low temperatures.