Production of levoglucosenone from pyrolysis of cellulose catalyzed by solid superacids

The pyrolysis of cellulose to produce levoglucosenone (LGO) with solid superacids (SO₄²-/TiO₂ and SO₄²-/ZrO₂) as catalyst was investigated by Py-GC/MS. Non-catalytic pyrolysis of pure cellulose was firstly carried out to reveal the effects of pyrolysis temperature and time on the formation of LGO. Then the mechanic mixture of cellulose with an equivalent mass of the superacids (SO₄²-/TiO₂ or SO₄²-/ZrO₂) was subjected to fast pyrolysis to investigate their catalytic effect on the pyrolytic products. The results indicated that during the fast pyrolysis of pure cellulose, the LGO is mainly formed at low or medium temperatures through a combination of dehydration and depolymerization reactions. The superacids as catalyst can significantly promote the formation of LGO; the relative content of LGO in the product exceeds 60%.