Page 123 - Advances in bioenergy (2016)

Biomass catalytic pyrolysis seems to be a very promising technology that could result in a
marketable bio-oil to be finally used as transportation fuel. A catalytic biomass pyrolysis
system is simpler as compared with the biomass to liquid process, whereas catalytic pyrolysis
oil can be produced in the region where the biomass is generated. This will stimulate the local
(decentralized) use of biomass for green transportation fuels. A lot of research is now in
progress for the development and evaluation of new catalysts for the catalytic biomass
pyrolysis producing a bio-oil with less oxygen content, as compared with the conventional bio-
oil. The research till today has shown that the presence of a catalyst in biomass pyrolysis can
significantly affect the bio-oil yield and quality. Zeolites constitute a promising class of

heterogeneous catalysts, and developments in recent years have demonstrated their potential to
find broad use in the conversion of biomass. ZSM-5 catalysts seem to be very active for this
process, as they crack the bio-oil giving lower yields (around 30 wt%) but with a better
quality (oxygen content around 21 wt%). This bio-oil is very promising and could be used as
bio-crude for the production of transportation fuels after a hydrotreating or a catalytic cracking
step.

Research challenges on biomass catalytic pyrolysis remain focused on the understanding of the
mechanism of the catalytic conversion of lignocellulosic biomass into bio-oil, including
structure–property relationships and product distribution, process conditions, and large-scale
production and also novel catalysts development that do not sacrifice the bio-oil yield for its
quality. Optimum catalyst development includes tailoring the porosity, acidity, basicity, metal–
support interactions, controlled formation of appropriate catalyst particles, improved
hydrothermal stability, and resistance to catalyst deactivation. It should be underlined that even
a small improvement in the quality of the bio-oil with a catalytic process would be beneficiary
for any downstream process of bio-oil upgrading.

NOTES

* Correspondence to: angel@cperi.certh.gr

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3. Williams P, Horne P. Analysis of aromatic hydrocarbons in pyrolytic oil derived from
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