Catalytic pyrolysis of cellulose with sulfated metal oxides: a promising method for obtaining high yield of light furan compounds.

Pyrolysis-gas chromatography/mass-spectrometry (Py-GC/MS) was employed to achieve fast pyrolysis of cellulose and on-line analysis of the pyrolysis vapors. Three sulfated metal oxides (SO(4)(2-)/TiO(2), SO(4)(2-)/ZrO(2) and SO(4)(2-)/SnO(2)) were prepared and used for catalytic cracking of the pyrolysis vapors. The distribution of the pyrolytic products was significantly altered by the catalysts. Those important primary pyrolytic products, such as levoglucosan and hydroxyacetaldehyde, were significantly decreased or even completely eliminated. Meanwhile, the catalysis increased three light furan compounds (5-methyl furfural, furfural and furan) greatly. In regard to the selectivity of the three catalysts, the SO(4)(2-)/SnO(2) was the most effective catalyst for obtaining 5-methyl furfural, while the SO(4)(2-)/TiO(2) favored the formation of furfural and the SO(4)(2-)/ZrO(2) favored the formation of furan.