Environmental Engineering Reference
In-Depth Information
states were starting operations, or were under construction/planning. Relatively
large plants can be found in Lithuania, Poland and Romania, with capacities of
100,000 tonnes/year. The conventional methodology for the production of biodiesel
involves the transesterification of triglycerides (TG) from vegetable oils (palm, corn,
soybean, rapeseed, sunflower, etc.) with short chain alcohols including methanol
and ethanol to yield fatty acid (m)ethyl esters (FAM/EE) and glycerol as by product
(Figs. 8.3 and 8.4).
Several reviews on the preparation of biodiesel from different feedstocks can be
found in the literature [12-15]. A very good overview of such technologies has been
TECHNOLOGIES
BIOFUELS
FEEDSTOCKS
Microbial (in)direct
photolysis/
Fermentation
Biohydrogen
Generic Biomass
Non edible
feedstocks (e.g
non-food crops,
microbial oil)
Transesterification/
Hydrogenation
Biodiesel
2
nd
Generation
biofuels
Anaerobic digestion
Biogas
Synthetic
fuels
Waste oils/fats
Gasification/ pyrolysis/
catalytic cracking
Wood, agricultural
and marine waste
Gasification/
Fermentation
Bioalcohols
Saccharification/
Fermentation
Sugar crops
Biobutanol
Oil crops
Biodiesel
and others
Transesterification
1
st
Generation
biofuels
Sugar and
starch crops
Fermentation
Bioethanol
Fig. 8.3
The biofuels ladder. Road map of biofuels production from feedstocks and technologies
O
O
R
O
OH
O
R
Y
O
+
O
3HY
+
OH
R´
O
T
=
50-70
o
C
Y
O
(Y = OMe,
OEt, OBut)
R"
OH
(Cat = NaOMe,
NaOEt, NaOH)
O
Y
R´
R"
Generic Triglyceride
Fatty acid methyl esters
Glycerol
(R,R',R" = C13-C23)
Fig. 8.4
Conventional transesterification of TG for the production of biodiesel
