Impacts of co-feeding alcohols on pyrolysis of cellulose

Abstract

Reactive atmosphere significantly affects pyrolysis of biomass, as the gases such as NH3 involves in the reaction network in pyrolysis. In this study, instead of feeding reactive gas, the impacts of co-feeding ethanol or glycol on the pyrolysis of cellulose were investigated at varied pyrolysis temperatures (400 and 600 °C). The results showed that the co-feeding of the alcohols affected yields of bio-char and tar, evolution of light organics and heavy organics, elemental composition, formation of fused ring structures, crystallinity, thermal stability, distribution of functionalities in the bio-char. The co-feeding of both glycol and ethanol enhanced the formation of the heavy components with the π-conjugated ring structures and affected the production of the light organics such as furfural and glycolaldehyde. Glycol or its derivatives cross-polymerized with the organics in bio-char, increasing bio-char yield and made the bio-char more oxygen-rich. Ethanol, however, showed the converse effects. Co-feeding of the alcohols promoted crystallinity but showed distinct effects on thermal stability of the bio-char at the varied pyrolysis temperatures. Both pyrolysis temperature and structures of the alcohols determined their extents of involvement in the pyrolysis of cellulose.