Ethylic biodiesel: the bottlenecks for
process optimization
Antonio J. A. Meirelles
Laboratory of Extraction, Applied Thermodynamics and
Equilibrium (EXTRAE)
School of Food Engineering (FEA)
University of Campinas (UNICAMP), São Paulo, Brazil
Co-workers: E. Batista, F. Batista, C. Rodrigues, C. Gonçalves. L.
Bessa, M. Ferreira, M. Cuevas, T. Deboni, T. Porcina, S.
Shiozawa.
Topics
1. Sources of fatty compounds for biodiesel
production.
2. Biodiesel nowadays: methanol vs.
ethanol.
3. An ethylic route for biodiesel production:
extraction, refining, trans/esterification,
purification and ethanol recovery.
Vegetable Oils in the World,
Million metric tons,
14/15 (USDA, 2015)
Crop
Corn
Soybean
Canola
Jatropha
Coconut
Palm
Oil yield
(L/ha)
172
446
1190
1892
2689
5950
Biodiesel in the World
Million m3
USA Germany Brazil Argentina
Source
Energy ratio
Microalgae
0.35 - 1.24
Palm
Soybean
Rapeseed
Sunflower
1.64 - 4.90
0.61 - 2.41
0.91 - 3.00
0.46 - 3.20
Brazil: 4th Soybean Oil, <<< 5th
Palm Oil, 3rd in Biodiesel, 2nd in
Bioethanol.
A controversial subject
1. Agro-ecological zoning by EMBRAPA on the deforested area of Amazon
(2007=13.94% of the Legal Amazon region): 29.7 million ha
appropriate for agricultural cultivation of oil palm (5,87% of the Legal
Amazon region). (Embrapa, 2010)
2. The area investigated by EMBRAPA is composed of  80% of degraded
and abandoned pastures.
3. Cultivation expansion restricted to the already deforested region
according to the images collected before 2008.
10.92
million ha used
1. 2007:
worldwide for oil
palm cultivation (C.
Carter et al. Eur. J. Lipid
Sci. Technol. 109 (2007)
307–314).
Malaysia +
Indonesia= (4+5)
million ha cultivation
of Palm (Homma, 2011).
2. Indonesia:
deforestation related
to the expansion of
oil palm cultivation
(Becker, CONFINS, 2010).
Agribusiness based on Palm Oil/Palm Biodiesel
is similar to that based on Sugar/Bioethanol
1.Oil palm trees/Palm oil: high productivity per
hectare.
2.Palm Oil/Palm Biodiesel Agribusiness uses
cogeneration based on palm tree residues. The
ratio bioenergy generated/fossil energy used 
Sugar Cane Bioethanol (World Watch Institute).
3.EMBRAPA: new varieties adapted to Brazilian
savannah (irrigation) and richer in unsaturated
fatty acids (Embrapa, 13/10/2010, 23/05/2011).
4.Researches on Hydrolysis of lignocellulosic
residues from palm tree (empty fruit bunches
and palm press fiber): coupling production of
palm oil biodiesel and bioethanol (Gutiérrez et al.,
Bioresource Technology, 2009).
“fatty acid methyl esters .. .are still among the most prominent alternative
biofuels, and there are still a lot of challenges …including the use of
ethanol instead of methanol” (M. Mittelbach, Editorial, Eur. J. Lipid Sci.
Technol. 2009, 111, 745–746).
FAEE X FAME GHG gains
Distillery (CD2) X
Sugar + Bioethanol (JP2)
GHG Emission
How to develop a feasible route for ETHYLIC BIODIESEL?
Our Approach: i) bioethanol can be used in the entire sequence of
biodiesel production, from the seed (oil extraction) to the tank; ii) the
main bottleneck is concentrated in the purification steps and recovery, in a
anhydrous form, of bioethanol used in excess.
Oil Extraction with Ethanol
Soybean
Oil
Nitrogen Solubility Index (%)
Extraction Yield (%)
1. Replacing hexane as solvent: extraction of oils for Biodiesel and for
edible purposes.
2. Recovering Nutraceuticals of high added value (oryzanol, tocopherols,
phytosterols, etc.) as byproducts or concentrated in the edible oil.
3. Future of the oil industry  biofuels + food + feed + high added value
products.
Temperature (°C)
Food Research International
62 (2014) 662-670
Oil Deacidification
By LLE with Ethanol
By Ion Exchange
▲ Rice Bran Oil
■ Free Fatty Acids
Breakthrough Curves
○ Soybean Oil
■ Free Fatty Acids
Solubility of anhydrous ethanol in palm oil at 45 oC
25 mass%  86 mol%
Ethanol/oil mol ratio = 6.14
1. Close to Ethanol boiling point, Vegetable Oils highly
soluble in Bioethanol.
2. Strong acid used in Ion Exchange regeneration can be
also used as the Esterification Catalyst.
Process Simulation and Catalysis
1. Process development based on experimental
studies and computer simulation (Aspen Plus)
2. Simulation requires suitable methods for the
calculation and prediction of properties, especially
phase equilibrium and reaction kinetics.
Biodiesel reaction is a
Two-Phase reversible
reaction
How the presence of two
phases affects the
reaction velocity? 
POSSIBLE MASS
TRANSFER INFLUENCE
k1
TAG  EtOH  DAG  BIOD
k2
k3
DAG  EtOH  MAG  BIOD
k4
k5
MAG  EtOH  GLYC  BIOD
k6
Palm Oil Conversion to Biodiesel
(▲) 308 K; (●) 323K; (■) 338 K.
Time (min)
Concentration (mole/L)
Conversion (%)
Reaction Kinetics at 338,15 K
♦, TAG; ■, DAG; ▲, MAG
×, Biodiesel; ○, Glycerol
Time (min)
LLE for Oil-FFA-Solvent: UNIFAC Parameters readjustment
Databank with 102 commercial fatty systems
360 (2013) 379– 391
LLE for TAG_Corn+DAG+MAG+Ethyl
linoleate+Ethanol at 303.15 K:●,
experimental; ─ NRTL; ∙∙∙∙∙∙
UNIFAC_LLE; --- ,UNIFAC_Readjust.
LLE for HOSO+DAG+MAG+ethyl
oleate+oleic acid+ethanol at T =
303.15 K: ●, experimental; - - - -,
UNIFAC-LLE; ∙∙∙∙∙∙, UNIFAC-Readjust.
JCT, 89
(2015),
148-158
Fluid Phase Equilibria,
404 (2015), 32-41
Biodiesel Purification + Ethanol Recovery
Purification of Ethylic Biodiesel
1. Phase splitting and decanting: (biodiesel rich +
glycerol rich) phases.
2. Ethanol evaporation, dehydration and recycling.
3. Biodiesel washing and drying.
Main Problem: Ethanol Recycling
1. Anhydrous bioethanol contains  0.5 m% Water.
2. Without dehydration bioethanol recycle accumulates
water.
Ethanol Dehydration
1. 3 Industrial Techniques: Extractive Distillation with
EG, Azeotropic Distillation with CH, Molecular Sieve.
2. Not the best solution: expensive in comparison to
Methanol dehydration (no Azeotropy)
Ethanol Dehydration with Ethylene Glycol
Almost 1/3 of the Brazilian Production
Industrial Installations for 300 to 1.000 m3/day
Water
Anhydrous
Bioethanol
Hydrated
Bioethanol
Ethanol
Dehydration
(dehydrant free basis)
yethanol
GLYCEROL´s
EFFECT on
Ethanol +
Water VLE
similar to the
observed for
Ethylene
Glycol
1.0
0.8
0.6
0.4
Glycerol-50 m%
Glycol-50 m%
0.2
Ethanol-Water
Azeotrope
0.0
0.0
0.2
xethanol
0.4
0.6
0.8
(dehydrant free basis)
1.0
Process for ethylic biodiesel
1.
2.
3.
4.
Byproduct GLYCEROL used for dehydrating Bioethanol to be recycled;
Ethanol as new reactant can be fed to the process as hydrous ethanol
and be dehydrated also using glycerol.
Glycerol recycles around 10 times in the installation, being withdrawn
before harmful effects can occur.
Two Brazilian patents (INPI) for deacidifying vegetable oils and for
producing biodiesel.
Ethanol
TAG
MAG
E/O=6:1
Concentration/ mole/L
Biodiesel
Glycerol
DAG
60 oC
Time/ h
Time/ h
■ Kg Steam/L Biodiesel
 Oil Conversion/ %
Molar Ratio Ethanol/Oil
■Biodiesel
Ethanol
Oleic/Linoleic Acids
60 oC
E/A=15:1
Biodiesel Loss, %
Concentration/ mole/L
Aspen Simulation
Molar Ratio Ethanol/Oil
CONCLUSION
Possibilities to integrate the production of
biofuels and edible oils have been
researched and developed in the case of
ethylic biodiesel.
Thank you for
your attention
Acknowledgments: