1 research outputs found
Fast Pyrolysis of Heartwood, Sapwood, and Bark: A Complementary Application of Online Photoionization Mass Spectrometry and Conventional Pyrolysis Gas Chromatography/Mass Spectrometry
Wood
offers important potential for biofuel or chemical production
by fast pyrolysis but exhibits variable chemical composition that
impacts pyrolysis product composition. Here, fast pyrolysis of heartwood,
sapwood, and bark isolated from Douglas fir (softwood) and oak (hardwood)
was studied by a microfluidized bed reactor (MFBR) combined with single
photoionization mass spectrometry (SPIāMS) to provide insights
into the wood zone effects on the composition of pyrolysis volatiles.
The difference in pyrolysis volatile composition has been clearly
unraveled by principle component analysis (PCA) based on the major
ions detected by SPIāMS. Some specific product markers have
been defined for each wood zone (heartwood, sapwood, and bark) and
related to the chemical composition of wood samples (lignin, carbohydrates,
and minerals). The catalytic effect of minerals (notably potassium)
has a higher impact on carbohydrate decomposition than on lignin decomposition
for a given wood type. Therefore, sapwood and heartwood (for both
oak and Douglas fir) can be clearly discriminated by specific markers
mainly from carbohydrate pyrolysis. Interestingly, our results show
that the wood cylinders exhibit a more marked wood zone effect on
product compositions compared to fine powders. SPIāMS results
were further compared to those of pyrolysis gas chromatography/mass
spectrometry (PyāGC/MS), and many of them are consistent. MFBR
combined with SPIāMS is a selective analytical technique to
figure out the effect of wood composition on pyrolysis volatiles