1 Biodiesel: Preparation, properties, advantages & disadvantages
Yomen ATASSI
2 Outline Introduction Definition Revision: triglyceride, fatty acids,…
History Comparison: Biodiesel-Petrodiesel Advantages and disadvantages of biodiesel Environment Diesel Engine Industrial process Prototype synthesis Perspectives
3 Introduction Environmental issues: 30% Increase
Burning fossil fuels increases atmospheric levels of carbon dioxide. Fossil fuels are a finite resource. 30% Increase Graph taken from USF Oceanography webpage
4 Introduction-continue
Why not use feedstock vegetable oil directly? More viscous than petrodiesel . Glycerol can cause carbon build-up in the pistons and fuel injectors of diesel engines.
5 Introduction-continue
Biofuel Biodiesel alcans Methyl esters Bioethanol
6 Definition Biodiesel refers to a non-petroleum- based diesel fuel consisting of short chain alkyl (methyl or ethyl) esters, made by transesterification of vegetable oil, which can be used (alone, or blended with conventional petrodiesel) in unmodified diesel- engine vehicles.
7 Definition-Continue Methyl_Linoleate
8 Revision-Fatty acids Linoleic acid
9 Revision-Triglyceride
10 Revision-continue:Transesterification
Fatty Acid Alcohol Glycerin
11 History In 1937 G. Chavanne, belgian patent 'Procedure for the transformation of vegetable oils for their uses as fuels'. in 1977, Brazilian scientist Expedito Parente produced biodiesel using transesterification with ethanol (patent). Currently, Parente's company Tecbio is working with Boeing and NASA to certify bio-Kerosene Global biodiesel production reached 3.8 million tons in Approximately 85% of biodiesel production came from the European Union.
12 History- continue In 2005, DaimlerChrysler released Jeep Liberty CRD diesels with 5% biodiesel blends. In 2007, DaimlerChrysler indicated intention to increase warranty coverage to 20% biodiesel blends. The world's first biofuel-powered commercial aircraft took off from London’s Heathrow Airport on February 24, 2008 and touched down in Amesterdam.
14 Comparison between Biodiesel and Petrodiesel
Composition(% w) Carbon Hydrogen Oxygen 84-87 13-16 77-81 11-12 7-12 Density at 150C 0.88 Boiling point (0C) Solubility in water (50 ppm)
15 Environmental advantages of Biodiesel
Less CO2 emissions. Use animal fat, non-edible vegetable oils, feedstock vegetable oils (recycling method). No sulfur compounds, so no acid rain. Biodrgradable, renewable, Indigenous. Safe. Low odor, no smoke.
16 Environmental disadvantages of Biodiesel
More NOx productions (5%).
17 Advantages for diesel-engine performance
Miscible with petrodiesel ( Blends of biodiesel and petrodiesel from B00-B100). High Lubricity and no sulfur content. Improves cetane index Solvent properties: break down deposits of residue in the fuel lines where petrodiesel has been used. Biodiesel is 3 1/2 times more energy efficient than bioethanol . For every 1 tonne of biodiesel that is manufactured, 100 kg of glycerol are produced
18 Disadvantages for diesel-engine performance
Non-controllable stability. High cloud point (about +50C). Hygroscopic properties. Less detonation power. The calorific value of biodiesel is about 33 MJ/L. This is 9 % lower than petrodiesel.
19 Industrial process Oil preparation Biodiesel synthesis
Free fatty acid esterification in excess of methanol (acid catalysis). Elimination of water and fatty acid using glycerol. Methanol distillation. Biodiesel synthesis Reaction of (triester+methylic ester) with NaOH in MeOH. (6 equiv. MeOH:1 equiv. oil). Aqueous washing to eliminate MeOH, glycerol, NaOH.
20 Industrial process-continue
Why using MeOH? Low molecular weight ester. Cheap. More efficient transesterification reaction. Shorter Reaction time than ethanol.
21 Synthesis-IR spectrum of glycerol
22 Synthesis-continue: IR spectrum of corn oil and BD
23 Synthesis-continue: NMR spectrum of Methyl Oleate
24 Synthesis-continue: NMR spectrum of BD-corn oil
25 Synthesis-continue: NMR spectrum of BD-olive oil
26 Perspectives Heterogeneous catalysis.
Second generation of biodiesel (algae, Honge oil and Jatropha): Advantages of algae grow on non-arable land (deserts, marine environments). Oil yields are much higher. Energy density is better.