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Catalytic pyrolysis characteristics of cardboard by bimetal-modified HZSM-5 (HZ) had been studied in this paper. Four kinds of metals, meaning Ni, Ca, Al and Pt were chosen as active metals. First they were loaded on HZ separately (each metal 0.5wt%), and then Pt/Ni, Pt/Ca and Pt/Al (each metal 0.25wt%) were loaded together on HZ, respectively. An analytical Py-GC/MS was used to test their catalytic activities. The results show that the quality of pyrolysis products without catalyst is relatively poor. With monometalmodified HZ catalysts, yield and selectivity of aromatic hydrocarbons increase obviously. The bimetal-modified catalysts (except Pt/Al-HZ) produce even more furans and aromatics than monometal-modified ones. However, Pt/Al-HZ shows low activity on promoting the formation of aromatics. In conclusion, suitable metals co-loaded on HZSM-5 could greatly increase the activities of the catalyst.

In order to study the pyrolysis behavior of different monosaccharides, pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique was used to determine the pyrolysates of seven monosaccharides, including ribose, xylose, fructose, sorbose, galactose, mannose and glucose. The results showed that: 1) Different monosaccharides had similar pyrolysates which could be classified into: furans, aldehydes, ketones, alcohols, esters, organic acids, etc. 2) Furfural, 5-methylfurfural, 5-hydroxymethylfurfural, 1,6-anhydro-β-D-glucopyranose, 2,5 - furandicarboxaldehyde and levoglucosenone occupied a higher percentage in pyrolysates of most monosaccharides. 3) Accompanied by aroma compounds, small quantities of harmful compounds were also generated during the pyrolysis of sugars, such as phenol, toluene, etc. 4) Moreover, the reasonable pyrolysis mechanisms of the important pyrolysates of different monosaccharides were discussed according to the classifications of aldopentose, aldohexose and ketohexose respectively.