Catalytic fast pyrolysis of biomass

Selected catalysts were screened or use in fast pyrolysis of biomass to upgrade the quality and quantity of bio-oil products. The screening was carried out using a Py-GC/MS microscale reactor followed by catalytic pyrolysis experiment on a bench scale fluidized bed reactor system with a scale o 150 g/hr biomass throughput. Cassava rhizome was used as the main biomass feedstock with selected catalysts including ZSM-5, Al-MCM-41, Al-MSU-F, copper chromite, proprietary commercial catalysts Criterion-534, and MI-575 as well as biomass ash. The mass balance closures for the catalytic pyrolysis experiment in the bench scale reactor were ≥ 95%. The presence of catalysts led to changes in product distribution especially in the organic fractions of the liquid bio-oil. Almost all the catalysts led to a decrease in organic yield accompanied with an increase of reaction water, secondary solid, and gases suggesting that the primary pyrolysis vapor has gone through severe dehydration and cracking reactions over the catalysts. Based on the volumetric gas composition, Criterion-534 favored production of hydrogen whereas ZSM-5 favored the production of olefins. According to the molecular weight distribution results of the bio-oil produced, most of the catalysts studied have the potential or improving bio-oils viscosity. This is an abstract of a paper presented at the 8th World Congress of Chemical Engineering (Montréal, Quebec, Canada 8/23-27/2009).