Product compositions and kinetics in the rapid pyrolysis of sweet gum hardwood

Journal Article · Tue Jan 01 00:00:00 EST 1985 · Ind. Eng. Chem. Process Des. Dev.; (United States)

DOI:https://doi.org/10.1021/i200030a053· OSTI ID:5667135

Nunn, T R; Howard, J B; Longwell, J P; Peters, W A

Yields, composition, and rates of evolution of major products from batch pyrolysis of predried sweet gum hardwood were measured for the temperature range 600-1400 K under 5 psig of helium, at heating rates and residence times at final temperature of 1000 K/s and 0 s, respectively. Approximately 100-mg layers of 45-88 ..mu.. m wood powder, thinly spread on a hot stage, were heated, so that volatiles residence times at elevated temperatures were minimized. Total weight loss increased strongly with temperature to an asymptote of 93% at 1100 K. Tar is the major pyrolysis product above 800 K. It exhibits a maximum yield of 55 weight % at 900 K and declines to an asymptote of 46 weight % at 1300 K. Secondary cracking of the tar is significant above 900 K and contributes substantially to the yields of CO, CH/sub 4/, C/sub 2/H/sub 4/, and other light gases. Carbon monoxide dominates the gas produced above 850 K and attains an asymptote of 17 weight % above 1300 K. A single-reaction first-order decomposition model describes well the global rates of evolution of most major products except tar. However, the data imply that most products are evolved by more complex kinetic pathways.

• Research Organization: Massachusetts Institute of Technology, Cambridge
• OSTI ID: 5667135
• Journal Information: Ind. Eng. Chem. Process Des. Dev.; (United States), Vol. 24:3
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
PYROLYSIS PRODUCTS
CHEMICAL COMPOSITION
WOOD
PYROLYSIS
CARBON MONOXIDE
CHEMICAL REACTION KINETICS
CRACKING
ETHYLENE
HELIUM
METHANE
POWDERS
TAR
TEMPERATURE MEASUREMENT
VOLATILE MATTER
WEIGHT MEASUREMENT
ALKANES
ALKENES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
ELEMENTS
FLUIDS
GASES
HYDROCARBONS
KINETICS
MATTER
NONMETALS
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
RARE GASES
REACTION KINETICS
THERMOCHEMICAL PROCESSES
090122* - Hydrocarbon Fuels- Preparation from Wastes or Biomass- (1976-1989)
140504 - Solar Energy Conversion- Biomass Production & Conversion- (-1989)