EXPERIMENTAL STUDY OF CELLULOSE FAST PYROLYSIS OVER SOLID CATALYSTS

NIEVA, MARÍA LUZ; VOLPE, MARÍA ALICIA; MOYANO, ELIZABETH LAURA

Foz do Iguaçu

Congreso; CLAFQO-12. 12th Latin American Conference on Physical Organic Chemistry; 2013

Biomass pyrolysis is a viable route for producing gases and liquids that can replace some petroleum-derived products. Also, the possibility of obtaining useful chemicals from biomass has also been demonstrated. It is commonly agreed that cellulose can be a model species for biomass because it is the most frequent and sometimes the most abundant biomass component. Several fast pyrolysis techniques have been suggested where variations in the contact time and temperature lead to completely different products1. The acid treatment of the starting cellulose as well as the incorporation of catalysts has an important influence on the course of the thermal degradation. The main purpose of this work was the development of a catalytic fast pyrolysis technique for supplying new data concerning to the cellulose pyrolysis mechanism at high temperatures and very low residence times. Thus, levoglucosan ( LG), and 5-hydroxy-cyclopenten-2-one (5-HC) were obtained as main products in the fast catalytic pyrolysis of crystalline cellulose using CeO2, Nb2O5, MCM-48, and AlFeMCM-41 as catalysts. The product distribution was affected by the temperature, starting cellulose and catalyst´s features. Thus, LG was the prevalent anhydrosugar in the bio-oil formed at 350 ºC using cellulose without phosphoric acid pre-treatment. By contrast, the acid-pretreated cellulose pyrolysis generated the ketone 5-HC as main product reducing the yield of LG. The high specific surface area of the mesoporous catalysts improved the yield of the main products in the liquid fractions, in contrast to the acidic and redox properties of the other catalysts employed. On the other hand, it was demonstrated that LG constitutes an intermediate for the formation of 5-HC and other products in the cellulose pyrolysis.