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240 Cha pte r Se v e n

the gasoline range. The results obtained by Piskorz et al. (1989) are
very interesting because it proved the feasibility of hydrotreating
decanted oils. In fact, the oils obtained from the slow pyrolysis reac-
tors and by high-pressure liquefaction are also decanted oils with
relatively low contents of polar compounds and tend to behave satis-
factorily during hydrotreatment. New hydrotreatment studies with
pyrolytic lignin (decanted oil) were carried out in 2005 by UOP LLC,
a Honeywell company, and Pacific Northwest National Laboratory
(PNNL) (Marinangeli et al. 2005). Two catalysts were tested. Although
PNNL used Pd on a carbon catalyst in a continuous pilot plant, UOP
used a Ni–Mo catalyst in a batch autoclave. The results obtained were
very similar to those obtained by Piskorz et al. (1989). The yield of
upgraded oils varies between 40 and 55 percent with an oxygen
removal of 69 to 93 percent. Between 30 and 60 percent of the bio-oil
was converted to naphtha.
UOP, PNNL, and NREL have recently shown (Holmgren et al.
2008) that although it is more difficult, the hydrotreatment of whole
bio-oils is also viable. There was 21 mass% of the oil converted to
distillable products with boiling points similar to naphtha and
another 21 percent was converted to compounds with boiling points
similar to diesel. The rest of the bio-oil was converted to CO , water,
2
and light hydrocarbons. Thus, around 28 mass% of the biomass can
be converted into fungible transportation fuel. These values are very
high if we take into account that current efforts at enzymatic hydro-
lysis only aim at producing 63.2 gallons of ethanol per ton of biomass
processed. The fast pyrolysis/hydrotreatment pathway could yield
148 gallons of ethanol equivalent per ton of biomass. Recent economic
analyses performed by UOP (Marinangeli et al. 2005) suggest that the
hydrotreatment of a bio-oil water-insoluble fraction is economically
viable at petroleum prices over $50 per barrel. Although hydrotreat-
ment of fast pyrolysis oils still requires more development to enable
large commercial operations, it is certainly one of the most promising
alternatives to convert biomass into transportation fuels.

7.7 Bio-Oil Refineries
The use of concepts like bio-based economy and biorefineries is not new,
but their importance has only been recognized recently. It is now gen-
erally accepted that biomass-derived products will have better oppor-
tunities to compete with our dominant petroleum economy.
The equilibrium between the cost of transportation and savings
associated with the economies of scale will determine the feasibility
of building centralized refineries near consumer centers, or distrib-
uted rural refineries closer to the biomass resources. The main goal of
a biorefinery is to produce high-value low-volume (HVLV) and low-
value high-volume (LVHV) marketable products at competitive cost