Abstract
Project 2 was initiated on 13 January 2006 based on a
proposal by Larry Russo (Office of Biomass Program, US
Department of Energy) to the IEA Bioenergy Executive
Committee. Dr Michael Ladisch (Laboratory of Renewable
Resources Engineering, Purdue University) joined as the
Project Co-Leader. A statement of work was then finalised
and submitted for approval by the Executive Committee
with a start date of June 1, 2006. The project co-leaders
worked with a team of participants from Finland, the
Netherlands, Sweden, UK, USA, and the European Commission
to develop a global view of gaps in research for
addressing production of second-generation liquid
biofuels. The Project 2 team developed its findings based
on inputs from participating countries through a series
of conference calls, published reports, and discussion
and review with experts who are carrying out work
associated with related Tasks within IEA Bioenergy.
Research gaps were found in cellulosic ethanol,
Fischer-Tropsch liquids and green diesel, dimethyl ether
and P-Series fuels.
Lignocellulosic ethanol is derived from pre-treatment,
hydrolysis, and fermentation of the resulting sugars from
cellulosic sources such as wood chips, agricultural
residues, and grasses. Green diesel is a high boiling
component, not derived from vegetable oil, obtained
either from Fischer-Tropsch synthesis or through
pyrolysis of biomass. Dimethyl ether has potential as a
high quality fuel for diesel engines and is produced by
converting syngas into methanol followed by dehydration
of methanol to dimethyl ether. P-Series fuel is a mixture
of ethanol, methyltetrahydrofuran, pentanes and higher
alkanes, and butane.
Methyltetrahydrofuran may be produced from dehydration of
pentose and glucose sugars to form furfural and levulinic
acid respectively, which when hydrogenated result in
methyltetrahydrofuran.
Common denominators in gaps for these different fuels and
the biochemical or thermochemical processes used to
produce them are given by three main areas. These are:
o catalysts and biocatalysts;
o feedstock preparation and bioprocessing; and
o systems integration.
In the biocatalyst (or catalyst) area research is needed
to achieve more robust, versatile, and cost-effective
catalysts. The catalytic systems must be less subject to
inhibition and more stable in the presence of chemically
complex feedstocks derived from biomass materials. With
bioprocessing, the gaps lie in economic enzyme
production, reduction of enzyme inhibition, development
of pentose utilising and cellulase producing
micro-organisms, feedstock preparation (pre-treatment),
and inhibitor removal. For thermochemical systems, the
list is analogous except the term 'catalyst' replaces
'enzyme' or 'microorganism'.
Gaps were identified in feedstock preparation, with this
term being broadly defined. Feedstocks are defined as
biomass materials entering the process, as well as gases
derived from biomass and used for catalytic formation of
diesel or other fuels. Pre-treatment of cellulosic
materials so that they are more efficiently converted to
fermentable sugars is one form of feedstock preparation,
and research that addresses the fundamental science and
process development of pre-treatments should be viewed as
a research gap. Clean-up of gases derived from biomass
before the gases enter a catalytic step is another
important research gap. Both areas impact on the
efficiency, longevity, and cost of biocatalysts and
catalysts.
Systems integration and the integration of bioengineering
with chemical engineering for cost-effective production
and use of second-generation fuels represents a third
research gap. This area encompasses gaps that must be
addressed in better understanding the infrastructure
required to deliver second-generation fuels and policies
that would accelerate their introduction to the market
place.
| Original language | English |
|---|---|
| Number of pages | 20 |
| Publication status | Published - 2008 |
| MoE publication type | D4 Published development or research report or study |