Effects of reaction temperature and molecular sieve catalyst on the distribution of pyrolysis products of biomass components

This study was carried out to examine the effects of reaction temperature and molecular sieve catalyst on the distribution of pyrolysis products of biomass components. The types and relative contents of compounds generated from the non-catalytic pyrolysis of microcrystalline cellulose (MC), xylan (XY), and alkaline lignin (AL) were markedly affected by temperature. Three primary components of biomass interacted during pyrolysis. The introduction of HZSM-5 into MC had no remarkable effect on the product distributions of bio-oils. MCM-41 improved the selectivity of aldehydes (from 2.00% to 41.58%), ketones (from 2.54% to 24.51%), furans (from 0% to 8.90%), and N-compounds (from 1.56% to 12.40%), while also inhibiting the formation of carbohydrate (from 87.95% to 5.38%) during the pyrolysis of MC. Compared with the non-catalytic pyrolysis of XY, HZSM-5 promoted the generation of alcohol (from 26.20% to 37.31%) and carbohydrates (from 16.29% to 27.61%), while reducing the proportion of N-compounds (from 13.96% to 4.09%). MCM-41 was favorable for the pro-duction of aldehydes (from 16.02% to 59.94%) and reduced the generation of alcohols (from 26.20% to 1.21%) and carbohydrates (from 16.29% to 3.79%). The HZSM-5-catalyzed pyrolysis of AL tended to produce greater amounts of acids (from 2.40% to 11.12%) but smaller amounts of phenols (from 58.01% to 36.66%). The relative contents of various classes of compounds during the pyrolysis of AL changed little in the presence of MCM-41.