关键词:

纤维素, 快速热解, 催化, Py-GC/MS, 金属氯化物

Abstract:

Cellulose was pretreated by impregnation of four metal chlorides (KCl, CaCl₂, FeCl₃ and ZnCl₂), and then subjected to fast pyrolysis by using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS).The pyrolysis products were on-line analyzed to reveal the catalytic effects of the four metal chlorides.The results indicated that the presence of metal chlorides reduced the pyrolysis temperature of cellulose.Moreover, the impregnation of CaCl₂ and FeCl₃ inhibited the devolatilization of cellulose considerably, while this was not the case for the impregnation of KCl and ZnCl2.Fast pyrolysis of pure cellulose produced abundant levoglucosan, some furans as well as light carbonyl compounds, mainly including hydroxyacetaldehyde.After the impregnation of metal chlorides, the formation of levoglucosan was deeply inhibited.KCl and CaCl₂ mainly promoted the depolymerization and dehydration of cellulose to form furans, and the pyrolytic ring scission to form various linear carbonyls and acids.FeCl₃ and ZnCl₂ mainly promoted the depolymerization and dehydration of cellulose to form anhydrosugars and furans.

Key words:

纤维素, 快速热解, 催化, Py-GC/MS, 金属氯化物