affected by structures of zeloite acid catalysts, but there is dependency of chemical
composition of the bio-oil on the structures. Ketones and phenols were the dominant
groups of compounds in the bio-oil. The formation of ketones was greater than that
of ZSM-5, and the amount of acids and alcohols was lower than that of the other bed
materials tested. Mordenite and quartz sand produced lower amounts of
polyaromatic hydrocarbons compared to other catalysts tested. Finished zeolites
can be regenerated successfully without deforming the structures of zeolite.
Wan et al. (2009) aimed at assessing the effects of the catalysts on the selectivity
of the pyrolysis product assisted by microwave cornstalks and aspen. Oxides, salts
and metal, including K 2 Cr 2 O 7 , Al 2 O 3 , KAc, H 3 BO 3 , Na 2 HPO 4 , MgCl 2 , AICl 3 ,
CoCl 2 and ZnCl 2 , were premixed with corn stalks or wood pellets especially for
pyrolysis using microwave heating. The thermal process produced three product
fractions, namely, bio-oil, gas and charcoal. The effects of catalysts on fractional
yields have been studied. It was found that the yield of the bio-oil efficiency of coal
or gas increased with KAc, Al 2 O 3 , MgCl 2 , H 3 BO 3 and Na 2 HPO 4 . These catalysts
can accelerate as absorbents for microwave heating or take part in a recovery in situ
pyrolytic vapour during the pyrolysis of biomass assisted by microwaves. GC-MS
analysis of the bio-oils revealed that the chloride salts favoured some reactions while
suppressing most of the other reactions observed for the control samples. In a
biomass of 8 g MgCl2/100, the total ion chromatograms GC-MS bio-oil from the
corn stalk or aspen treated shows one main peak of furfural covering about 80% of
the acreage spectrum. It was concluded that some catalysts enhance bio-oil yields,
and in particular chloride salts simplify the chemical composition of the resulting
bio-oil and thereby improve product selectivity of the pyrolysis process.
Fahmi et al. (2008) focused on the pyrolysis of four reference fuels and three
low-lignin Lolium-Festuca grasses to produce pyrolysis oils. The oils were analysed
to determine their quality and stability, which made it possible to identify the
properties of the raw materials that influence the stability of the oil. Two washed
raw materials were also subjected to pyrolysis to determine if a wax could improve
the quality of the pyrolysis oil. Minerals appeared to have a dominant effect on
pyrolysis compared to the lignin content, in terms of pyrolysis yields for organic
matter, coal and gases. However, the higher molecular weight compounds present in
the pyrolysis oil are due to the lignin-derived compounds as determined by the
results of GC and liquid GC/MS. The yield of the light organic fraction also
increased, but its water content was lowered as the metals increased at the expense
of the lignin content. It has been found that the fresh oil and the aged oil have
different intensities/concentrations of compounds, which is the result of a large
number of reactions that occur during daily oil aging. These results are consistent
with previous reports suggesting that a large amount of repolymerisation occurred,
since the levoglucose yields increased during aging, while hydroxyacetaldehyde
decreased. In summary, the article describes a window for producing a more stable
pyrolysis oil using energy crops and also shows that washing with biomass can
improve the quality and stability of the oil for high-quality raw materials, in the ash,
but less for energy crops.
12 Modelling and Simulation of Pyrolysis of Teak (Tectona Grandis) Sawdust
337
composition of the bio-oil on the structures. Ketones and phenols were the dominant
groups of compounds in the bio-oil. The formation of ketones was greater than that
of ZSM-5, and the amount of acids and alcohols was lower than that of the other bed
materials tested. Mordenite and quartz sand produced lower amounts of
polyaromatic hydrocarbons compared to other catalysts tested. Finished zeolites
can be regenerated successfully without deforming the structures of zeolite.
Wan et al. (2009) aimed at assessing the effects of the catalysts on the selectivity
of the pyrolysis product assisted by microwave cornstalks and aspen. Oxides, salts
and metal, including K 2 Cr 2 O 7 , Al 2 O 3 , KAc, H 3 BO 3 , Na 2 HPO 4 , MgCl 2 , AICl 3 ,
CoCl 2 and ZnCl 2 , were premixed with corn stalks or wood pellets especially for
pyrolysis using microwave heating. The thermal process produced three product
fractions, namely, bio-oil, gas and charcoal. The effects of catalysts on fractional
yields have been studied. It was found that the yield of the bio-oil efficiency of coal
or gas increased with KAc, Al 2 O 3 , MgCl 2 , H 3 BO 3 and Na 2 HPO 4 . These catalysts
can accelerate as absorbents for microwave heating or take part in a recovery in situ
pyrolytic vapour during the pyrolysis of biomass assisted by microwaves. GC-MS
analysis of the bio-oils revealed that the chloride salts favoured some reactions while
suppressing most of the other reactions observed for the control samples. In a
biomass of 8 g MgCl2/100, the total ion chromatograms GC-MS bio-oil from the
corn stalk or aspen treated shows one main peak of furfural covering about 80% of
the acreage spectrum. It was concluded that some catalysts enhance bio-oil yields,
and in particular chloride salts simplify the chemical composition of the resulting
bio-oil and thereby improve product selectivity of the pyrolysis process.
Fahmi et al. (2008) focused on the pyrolysis of four reference fuels and three
low-lignin Lolium-Festuca grasses to produce pyrolysis oils. The oils were analysed
to determine their quality and stability, which made it possible to identify the
properties of the raw materials that influence the stability of the oil. Two washed
raw materials were also subjected to pyrolysis to determine if a wax could improve
the quality of the pyrolysis oil. Minerals appeared to have a dominant effect on
pyrolysis compared to the lignin content, in terms of pyrolysis yields for organic
matter, coal and gases. However, the higher molecular weight compounds present in
the pyrolysis oil are due to the lignin-derived compounds as determined by the
results of GC and liquid GC/MS. The yield of the light organic fraction also
increased, but its water content was lowered as the metals increased at the expense
of the lignin content. It has been found that the fresh oil and the aged oil have
different intensities/concentrations of compounds, which is the result of a large
number of reactions that occur during daily oil aging. These results are consistent
with previous reports suggesting that a large amount of repolymerisation occurred,
since the levoglucose yields increased during aging, while hydroxyacetaldehyde
decreased. In summary, the article describes a window for producing a more stable
pyrolysis oil using energy crops and also shows that washing with biomass can
improve the quality and stability of the oil for high-quality raw materials, in the ash,
but less for energy crops.
12 Modelling and Simulation of Pyrolysis of Teak (Tectona Grandis) Sawdust
337