Biodiesel WWW Encyclopedia
All the Answers. All the Links
Comprehensive resources for castor crop, castor oil and castor oil derivatives (also CO Dict)
The main page for the Plant Oils section
WWW resources for various uses of plant oils
Edible oil resources
Plant oil uses in cosmetics, fragrances, toiletries
Plant oil uses in medicine, drugs and in pharma industry
Plant oil uses as bio-fuels and bio-diesel
Studies and research on uses and future trends in plant oils
Gunms, gels, extracts, polymers, acids, waxes, dyes and enzymes
WWW resources for over 200 plant oils
Other Sites from eSource
The Biodiesel WWW Encyclopedia provides comprehensive info & WWW resources for bio-diesel. It provides inputs and info on various aspects of biodiesel, and over a thousand relevant web links on biodiesel related topics. It is intended to be a one-stop biodiesel resource, both for information and for WWW links, and is expected to be of use to beginners and experts alike.
While many of you might have only read about biodiesel in passing, it is important to realize that all of us should be more concerned about biodiesel and related renewable, bio-energy sources, as these will affect us a lot more than it appears at first glance. The world is facing an energy crisis (Oh well, when hasnt it been!). Of specific significance is threat posed by the volatile and diminishing nature of fossil fuels (Fossil Fuel from University of Michigan), especially petro-products such as gasoline and diesel.
The 1970s energy crises (The 1973 Oil Crisis Wikipedia), and the recent upheavals in the oil market leading to record oil prices, have again turned the world attention to alternative sources of energy. A number of them are being researched nuclear energy (FAQ on Nuclear Energy, Nuclear Energy from the Energy Story, Nuclear Energy - from Wikipedia), fuel cells (How Fuel Cells Work from How Stuff Works, Fuel Cell Today, Fuel Cell Vehicles from Fuel Economy.gov), hydrogen energy (Hydrogen Energy Center, Hydrogen Energy Resources from US Dept of Energy), wind energy (Wind Energy from the Energy Story, Wind Energy Resources from US Dept of Energy), solar (Solar Energy Resources from US Govt Dept of Energy, International Solar Energy Society) and bio-energy (Bioenergy Information Network, Govt of USA). Use of nuclear energy and hydrogen energy for civilian purposes are in very nascent stages. Fuel cells are more promising, but they are yet to be put in commercial practice. Wind energy and solar energy already find use in a good number of applications though they have their own limitations.
The bio-energy alternative, while it has its limitations as well, is exciting because it provides us with easily available fuel that can fit into todays gasoline and diesel engines with minimal or no changes to existing systems.
Of the bio-energy alternatives, one exciting trend is biodiesel the manufacture and use of diesel-like substitute from plant and animal fats. The Biodiesel WWW Encyclopedia section is about everything Biodiesel.
For the common you and me, biodiesel should be of more than a passing interest. As a wise man put it succinctly, the whole world today runs on two things: money (in the unlikely scenario that you do not know much about money - Money from Wikipedia) and oil, and not necessarily in that order. Money, at least theoretically, is inexhaustible if your country runs out of cash, well, the central bank (Central Bank - from Wikipedia) can print more of it, even if it raises a few eyebrows at the IMF (IMF Homepage). But not oil, sir. Oil from fossil fuel is running out and is non-renewable (Non-renewable Energy Definition).
So, it is not a question of if? It is not even a question of when estimates that suggest that we will run out of oil in the next about 100 years if not earlier.
Hence, the time to start thinking about alternate energy forms is now. Else, it will be too late.
Objective of the Biodiesel WWW Encyclopedia
The objective is to provide resources and links in an objective manner such that one is able to get information on all aspects of bio-diesel. While it is indeed true that bio-diesel has many virtues, it is still in its initial phase of application, and there are many aspects to be considered before complete endorsement can be provided for these fuels. This section attempts to provide resources so that a researcher is able to find content that can give her/him good understanding of all the relevant aspects, and about ongoing research and explorations in many areas of this exciting field.
The Biodiesel WWW Encyclopedia tries to achieve its objective by providing:
1. Brief but hopefully useful content and information on a number of aspects of biodiesel
2. An extensive number of related web resources and links
Through this two-pronged approach, it is hoped that the user will be able to (a) get an analytical insight of the various aspects in the biodiesel framework, and (b) easily access the best of the content available on the web for all these aspects.
Why is it called the WWW Encyclopedia?
It is named the Biodiesel WWW Encyclopedia and not the Biodiesel Encyclopedia for the reason that it is comprehensive both in terms of original content as well as in the provision of WWW links. The WWW Encyclopedia currently contains over 1,500 web links related to biodiesel, and is one of the largest web links directory for biodiesel.
The Biodiesel WWW Encylcopedia will be of use to the following audience
1. A beginner wishing to know the basics of biodiesel
2. An industry professional looking for web resources for specific aspects of biodiesel
3. Those wanting to know how to produce biodiesel
4. Those looking for resources for research and future trends in biodiesel
5. Those looking for inputs on the various plant oils that can be used as feedstock for biodiesel
6. Those wanting to know the usage of biodiesel in their respective geographies.
Comprising over twenty sections, The Biodiesel WWW Encyclopedia provides information and resources for over two hundred different aspects of biodiesel.
We hope you find this to be of use.
Add Links: If you are a web site owner wishing to give a link to the Biodiesel WWW Encyclopedia, please go ahead, it will be our pleasure to be of help to your sites visitors. If you have a web site that you wish to include in this database, do let us know the details by sending a note about your URL to [email protected]. Well quickly review the web site, and if found relevant, add it to the database. Thanks!
Ask Us: Please send us any questions you have on biodiesel, and we will try our best to answer them and provide relevant web resources for the same. You may kindly send your questions to [email protected] . You may also send us your suggestions and feedback to the same email address. We look forward to hearing from you.
Using Content from the Encyclopedia: Anyone is free to use the content from The Biodiesel WWW Encyclopedia on or off the web. You may use any amount of content from the Encyclopedia at absolutely no cost and with no conditions. We would be grateful if you could acknowledge the source and if the content is used online, also provide a link back to The Biodiesel WWW Encyclopedia. This is only a request!
See also: Oilgae.com Biodiesel from Algae
Sections @ the Biodiesel WWW Encyclopedia
Biofuel definition, basics
Biodiesel definition, composition, & bio-diesel chemistry
Where did it start, how did it happen
Biodegradability, non-toxicity, fewer emissions, renewability
Definition of calorific value, cloud point, flash point, melt point, flash point, iodine value, viscosity, cetane number
Links, differences between diesel & gasoline
Links, differences between gasoline & diesel engines
Inputs on biofuels in the context of gasoline engines, biogasoline
About transesterification, dilution, microemulsion, thermal decomposition, catalytic cracking
Plant oils discussed: Rapeseed, palm oil, castor oil, sunflower, safflower, hemp, mustard, soybean, jatropha, algae, radish, artichoke, canola oil, corn oil, rice bran oil, peanut oil, cottonseed oil, coconut oil, tung oil, milk bush, karanj
11. Ethanol as Fuel
Ethanol links, Ethanol & Biodiesel compare & contrast
Links for biodiesel economics, cost-benefits and sustainability
Biodiesel in various countries: North America (USA, Canada, Mexico), Europe (UK, France, Germany, Italy, Spain ), South America (Brazil, Argentina, Chile ), Asia (India, China, Japan ), Australia
Links to biodiesel forums, discussion groups and bio-diesel blogs
Research links for biodiesel technology, bio-diesel production & applications
Links to web sites that in turn provide links and directories for various aspects of biodiesel
News articles, editorials and op-eds on biodiesel and biofuels
Answers & links to questions such as: How long would petrol last? What are the key disadvantages of bio-diesel?...and more
Biodiesel Links A-Z
Oilseed yields, diesel fuel standards, viscosity data
Classes of biofiels, energy content for biofuels
Peak oil & more
Section 1. What is a biofuel?
Biofuel is any fuel that derives from biomass recently living organisms or their metabolic byproducts. Thus it could be oils from plants, manure from cows, wood from trees and so on. It is a renewable energy source (NREL, Renewable Energy.com), unlike other natural resources such as petroleum, coal and nuclear fuels. (see: Biomass Energy Home Page, Dept of Energy, Govt of USA, Biomass Research Home Page - NREL, Bio-mass Introduction from TERI, India, Biomass Energy The Energy Story, Govt of Canada, Biomass - from Wikipedia)
History of Biofuels
Agricultural products specifically grown for use as biofuels include corn and soybeans, primarily in the United States, and flaxseed and rapeseed, primarily in Europe. Waste from industry, agriculture, forestry, and households can also be used to produce bioenergy; examples include straw, lumber, manure, sewage, garbage and food leftovers. Most biofuel is burned to release its stored chemical energy (Is it Easy to Store Energy?), though research is active into more efficient methods of converting biofuels and other fuels into electricity (see Biomass 101 Apollo Alliance) utilizing fuel cells (see: Fuel Cells .org, How Fuel Cells Work from How Stuff Works).
The production of biofuels to replace petroleum-based oil and natural gas is in active development. The carbon in biofuels was recently extracted from atmospheric carbon dioxide by growing plants, so burning it does not result in a net increase of carbon dioxide in the Earth's atmosphere (see: Atmospheric Carbon-dioxide). As a result, biofuels are seen by many as a way to reduce the amount of carbon dioxide released into the atmosphere by using them to replace non-renewable sources of energy.
To summarise, biofuels are fuels derived from plants and animals. Lets call the plant-based biofuels as botafuels and the animal-based ones as zoofuels.
Biofuels from plants could be derived from plant oils, leaves, wood and twigs, and related plant extracts.
see also: Liquid Fuels from Plants IISc India (PDF), Plant Oils Give Petroleum a Run for their Money - CNN, Plant & Crop Based Renewable Fuels 2020 Dept of Energy, Govt of USA (PDF), Agriculture-based Renewable Energy Production CRS Report for Congress (PDF)
Biofuels from animals could be from animal fats/lipids, and from the animal waste.
More Biofuel Links
Section 2. What is bio-diesel?
Biodiesel refers to any diesel-equivalent biofuel made from renewable biological materials such as vegetable oils (Vegetable Oil from Wikipedia) or animal fats (Animal Fats fro Wikipedia). While there are numerous interpretations being applied to the term biodiesel, the term biodiesel usually refers to an ester, or an oxygenate, made from the oil and methanol (in other words, the name biodiesel can be applied to any transesterified vegetable oil that makes it suitable for use as a diesel fuel).
Technically, as mentioned earlier, biodiesel is vegetable oil methyl ester (Esters & Fatty Acid Methyl Esters from Wikipedia), or in general one could say that biodiesel consists what are called mono alkyl-esters (Alkyl Esters Specs & Specification Charts from Rohm Hass). It is usually produced by a transesterification and esterification (Esters & Esterification from Aus-Tute) reaction of vegetable or waste oil respectively with a low molecular weight alcohol, such as ethanol (Ethanol from Journey to Forever) and methanol (Methanol from UCC, Ireland). During this process, the triglyceride (Triglyceride from Wikipedia) molecule from vegetable oil is removed in the form of glycerin (soap). Once the glycerin is removed from the oil, the remaining molecules are, to a diesel engine, somewhat similar to those of petroleum diesel fuel. There are some notable differences though. While the petroleum and other fossil fuels contain sulfur, ring molecules & aromatics (Aromatics Online), the biodiesel molecules are very simple hydrocarbon chains, containing no sulfur, ring molecules or aromatics. Biodiesel is thus essentially free of sulfur and aromatics. Biodiesel is made up of almost 10% oxygen, making it a naturally "oxygenated" fuel.
The concept of using vegetable oil as a fuel dates back to 1895 when Dr. Rudolf Diesel (Rudolf Diesel from Hemp Car) developed the first diesel engine to run on vegetable oil. Diesel demonstrated his engine at the World Exhibition in Paris in 1900 using peanut oil as fuel.
Bio-diesel can be used in diesel engines either as a standalone or blended with petro diesel. Much of the world uses a system known as the "B" factor to state the amount of biodiesel in any fuel mix. For example, fuel containing 20 % biodiesel is labeled B20. Pure biodiesel is referred to as B100.
Similar to biofuels, biodiesel can be derived from the triglycerides (fats) of either plants or animals, though a very large percetange of biodiesel is today derived from plant oils. Lets call the plant-based bio-diesel as botadiesel, and the animal-based biodiesel as zoodiesel.
As mentioned earlier, plant oils form the feedstock for a very large percentage of the biodiesel in use today. While the most popular plant oils in this regard are from sunflower, soybeans, jatropha, corn, canola, safflower & rapeseed oil, experiments are going on for many more plants to check if their oils could be suitable candidates for biodiesel. More information on the various plant oils that can be used for biodiesel are given in a later section.
Biodiesel from animal fat is much less prevalent than biodiesel from the plant counterparts, but a good amount of research is going on in this area. A few studies suggest that biodiesel from animal fats could cost significantly less (about 20%) than that from plant oils because animal fat is cheaper than fats from plant oils. Some links on the use of animal fat as biodiesel:
biodiesel from thermal depolymerization of particular wastes (wastes from the meat processing industry, old tires, landfill biomass, etc.).
Other Candidates for Biodiesel
· Bio-Dimethyl Ether (Bio-DME): is promising fuel for diesel engines due to its combustion and emission properties and could become of great interest for very low GHG vehicles. It is similar to LPG (a mixture of propane and butane) in terms of physical characteristics and can be used as substitute for LPG or as oxygenated addictive in gasoline, as a blending component of diesel fuel in which it is easily soluble, or as diesel-fuel substitution for modified diesel engines. At present DME is produced from pure methanol by an acid catalyst.
· To round off this section, a summary of the various entities that can be considered for blending with petro-diesel in diesel engines, or used alone ( as in pure biodiesel - B100):
· Biodiesel: a methyl-ester produced from vegetable or animal oil, of diesel quality. This is what this page is all about.
· Biodimethylether: dimethylether produced from biomass
· Fischer Tropsh: Fischer Tropsh produced from biomass
· Cold pressed bio-oil: oil produced from oil seed through mechanical processing only
Section 3. Biodiesel History
Contrary to what you might feel, biodiesel is not new. The process of transesterification of vegetable oil has been in vogue for over a hundred years, though the process was mainly used to derive glycerin from vegetable oils. The by-products of such a process were methyl esters, the biodiesel of today!
Even in terms of usage, biodiesel is hardly new. Rudolf Diesel used peanut oil in his original compression-ignition engine in 1898! In fact, the general feeling in the early 20th century was that vegetable fuels (biodiesel) will be the primary fuel for diesel engines, and were used until the 1920s, when petro-diesel made its entry.
Now that we have just begun to run out of petro-fuels, the vegetable based fuels, especially biodiesel, are again coming into currency. History does repeat, doesnt it?
Links on Biodiesel History
Section 4. Advantages of Biofuels & Biodiesel
Primary Advantages & Benefits
· Biodiesels are biodegradable (What is Biodegradability? from Ecomall)
· They are non-toxic (Toxicity, Bioddegradabilty & Environmental Benefirs of Biodiesel - PDF)
· They have significantly fewer noxious emissions than petroleum-based diesel, when burned (Biodiesel Emissions Data - PDF)
· They are renewable
· With a much higher flash point (Flash Point from Univ of Arizona) than it is for petro-diesel (biodiesels have a flash point of about 160 °C), biodiesel is classified as a non-flammable liquid by the Occupational Safety and Health Administration. This property makes a vehicle fueled by pure biodiesel far safer in an accident than one powered by petroleum diesel or the explosively combustible gasoline.
More Biodiesel Facts & Advantages
· Biodiesel is the only alternative fuel that runs in any conventional, unmodified diesel engine. (How Diesel Engines Work from How Stuff Works)
· Biodiesel can be used alone or mixed in any ratio with petroleum diesel fuel. The most common blend however is a mix of 20% biodiesel with 80% petroleum diesel, or "B20."
· Biodiesel is about 10% oxygen by weight and contains no sulfur. The lifecycle production and use of biodiesel produces approximately 80% less carbon dioxide emissions, and almost 100% less sulfur dioxide.
· Combustion of biodiesel alone provides over 90% reduction in total unburned hydrocarbons, and a 75-90% reduction in aromatic hydrocarbons. When burned in a diesel engine, biodiesel replaces the exhaust odor of petroleum diesel with the pleasant smell of popcorn or french fries. Biodiesel further provides significant reductions in particulates and carbon monoxide than petroleum diesel fuel. Thus, biodiesel provides a 90% reduction in cancer risks. In sum, the use of biodiesel will also reduce the following emissions:
- carbon monoxide (Carbon Monoxide Emissions from Carbon Monoxide Kills)
- hazardous diesel particulates of solid combustion products
- acid rain-causing sulfur dioxide (Info about Acid Rain, from EPA)
- lifecycle carbon dioxide
· The use of biodiesel can extend the life of diesel engines because it is more lubricating than petroleum diesel fuel (Biodiesel Lubricity from University of Idaho PDF), while fuel consumption, auto ignition, power output, and engine torque are relatively unaffected by biodiesel.
· Biodiesel is safe to handle and transport because it is as biodegradable as sugar, 10 times less toxic than table salt, and has a high flashpoint of about 300 F compared to petroleum diesel fuel, which has a flash point of 125 F. (Biodiesel Chemical Safety Data Oxford Univ)
· Biodiesel readily blends and stays blended with petrodiesel.
· Biodiesel has a very high flash point (300°F) making it one of the safest of all alternative fuels, from a combustibility point. (Biodiesel Flash Point from Biodiesel Now Forums)
· Biodiesel boasts of a zero total emissions production facility
· Neat vegetable oils pose some problems when subjected to prolonged usage in CI engine. These problems are attributed to high viscosity, low volatility and polyunsaturated character of the neat vegetable oils, and can be reduced significantly by subjecting the vegetable oils to the process of transesterification.
Useful Links: Biodiesel Factsheet
Section 5. Characteristics of Efficient Bio-fuels and Bio-diesels
Biodiesel is noteworthy for its similarity to petroleum-derived diesel fuel, while at the same time having negligible sulfur and ash content. Bioethanol (Bioethanol from Vogelbusch) has only about 70% the heating value of petroleum distillates such as gasoline, but its sulfur and ash contents are also very low. Both of these liquid fuels have lower vapor pressure (Vapor Pressure from Wikipedia) and flammability (Flammability from Wikipedia) than their petroleum-based competitors an advantage in some cases (e.g. use in confined spaces such as mines) but a disadvantage in others (e.g. engine starting at cold temperatures).
Despite their wide range of possible sources, biomass feedstocks (What is a Feedstock?) are remarkably uniform in many of their fuel properties, compared with feedstocks such as coal or petroleum. For example, there are many kinds of coals whose gross heating value (Heating Value Definition from Taftan.com ) ranges from 20 to 30 GJ/T (giga joules per metric tonne). However, nearly all kinds of biomass feedstocks destined for combustion fall in the range 15-19 GJ/T. For most agricultural residues, the heating values are even more uniform about 15-17 GJ/tonne (6450-7300 Btu/lb); the values for most woody materials are 18-19 GJ/tonne (7750-8200 Btu/lb).
However, in contrast to their fairly uniform physical properties, biomass fuels are rather heterogeneous with respect to their chemical elemental composition.
Most biomass materials are more reactive than coal, with higher ignition stability. This characteristic also makes them easier to process thermochemically into higher-value fuels such as methanol (Methanol as Fuel from Ethanol GEC) or hydrogen (Hydrogen Fuel Clean & Secure Energy White House).
Characteristics of Oils or Fats Affecting their Suitability for Use as Biodiesel
Calorific Value, Heat of Combustion Heating Value or Heat of Combustion, is the amount of heating energy released by the combustion of a unit value of fuels.
One of the most important determinants of heating value is moisture content. Air-dried biomass typically has about 15-20% moisture, whereas the moisture content for oven-dried biomass is negligible. Moisture content in coals vary in the range 2-30%. However, the bulk density (and hence energy density) of most biomass feedstocks is generally low, even after densification between about 10 and 40% of the bulk density of most fossil fuels. Liquid biofuels however have bulk densities comparable to those for fossil fuels.
Melt Point or Pour Point - Melt or pour point refers to the temperature at which the oil in solid form starts to melt or pour. In cases where the temperatures fall below the melt point, the entire fuel system including all fuel lines and fuel tank will need to be heated.
Cloud Point - The temperature at which an oil starts to solidify is known as the cloud point. While operating an engine at temperatures below an oils cloud point, heating will be necessary in order to avoid waxing of the fuel. (Cloud Point Definition from Engineers Edge)
Flash Point (FP) - The flash point temperature of diesel fuel is the minimum temperature at which the fuel will ignite (flash) on application of an ignition source. Flash point varies inversely with the fuels volatility. Minimum flash point temperatures are required for proper safety and handling of diesel fuel. (Flash Point from the MSDS Hyper Glossary, Flash Point from Wikipedia)
Iodine Value (IV) - Iodine Value (IV) is a value of the amount of iodine, measured in grams, absorbed by 100 grams of a given oil.
Iodine value (or Iodine number) is commonly used as a measure of the chemical stability properties of different biodiesel fuels against such oxidation as described above. The Iodine value is determined by measuring the number of double bonds in the mixture of fatty acid chains in the fuel by introducing iodine into 100 grams of the sample under test and measuring how many grams of that iodine are absorbed. Iodine absorption occurs at double bond positions - thus a higher IV number indicates a higher quantity of double bonds in the sample, greater potential to polymerise and hence lesser stability.
Iodine Numbers for some plant oils (before conversion into biodiesel):
· Coconut oil: 10
· Rapeseed oil: 94-120
· Soybean oil: 117-143
· Sardine oil: 185
Iodine Numbers after conversion to biodiesel through transesterification (approximate values):
· Rapeseed Methyl Ester (Rapeseed Biodiesel): 97
· Rapeseed Ethyl Ester (Another variety of Rapeseed biodiesel): 100
· Soy Ethyl Ester (Soy biodiesel variety 1): 123
· Soy Methyl Ester (Soy biodiesel variety 2): 133
One can hence see that the process of transesterification (conversion of plant oil int6o biodiesel) reduces the iodine value to a small extent.
Viscosity Viscosity refers to the thickness of the oil, and is determined by measuring the amount of time taken for a given measure of oil to pass through an orifice of a specified size. Viscosity affects injector lubrication and fuel atomization. Fuels with low viscosity may not provide sufficient lubrication for the precision fit of fuel injection pumps, resulting in leakage or increased wear. Fuel atomization (Atomization from Wikipedia) is also affected by fuel viscosity. Diesel fuels with high viscosity tend to form larger droplets on injection which can cause poor combustion, increased exhaust smoke and emissions.
Aniline Point/Cetane Number (CN) - Is a relative measure of the interval between the beginning of injection and autoignition of the fuel. The higher the cetane number, the shorter the delay interval and the greater its combustibility. Fuels with low Cetane Numbers will result in difficult starting, noise and exhaust smoke. In general, diesel engines will operate better on fuels with Cetane Numbers above 50.
Cetane tests provide information on the ignition quality of a diesel fuel. Research using cetane tests will provide information on potential tailoring of vegetable oil-derived compounds and additives to enhance their fuel properties. (References Cetane Number Testing of Bio-diesel from Biodiesel.org (PDF), Cetane Number from Sizes.com, How Does Cetane Number Affect Diesel Engine Operation? ).
Density Is the weight per unit volume. Oils that are denser contain more energy. For example, petrol and diesel fuels give comparable energy by weight, but diesel is denser and hence gives more energy per litre. (Fuel Density)
The aspects listed above are the key aspects that determine the efficiency of a fuel for diesel engines. There are other aspects/characteristics which do not have a direct bearing on the performance, but are important for reasons such as environmental impact etc. These are:
Ash Percentage - Ash is a measure of the amount of metals contained in the fuel. High concentrations of these materials can cause injector tip plugging, combustion deposits and injection system wear. The ash content is important for the heating value, as heating value decreases with increasing ash content.
Ash content for bio-fuels is typically lower than for most coals, and sulphur content is much lower than for many fossil fuels. Unlike coal ash, which may contain toxic metals and other trace contaminants, biomass ash may be used as a soil amendment to help replenish nutrients removed by harvest.
Sulfur Percentage - The percentage by weight, of sulfur in the fuel Sulfur content is limited by law to very small percentages for diesel fuel used in on-road applications. (Ultra-low Sulfur Diesel - PDF)
Potassium Percentage - The percentage by weight, of potassium in the fuel
Engine Manufactures Association (EMA) Recommended Guideline on Diesel Fuel
Source: Engine Manufacturers Association
More Links on Biodiesel Properties
Section 6. All about Petroleum Diesel
Diesel (the common term for petro-diesel) is a fractional distillate (Fractional Distillation from Chem Heritage, How Oil Refining Works from How Stuff Works, Fractional Distillation Definition from About.com) of petroleum used as fuel in a diesel engine, a type of Internal Combustion (IC) engine invented by German engineer Rudolf Diesel. Petro Diesel is about 18% denser than gasoline.
Diesel is generally simpler to refine than gasoline and usually costs less. Petro diesel typically releases about 40.9 megajoules (MJ) per liter when burnt, compared to gasoline which releases 34.8 MJ/L.
Petro diesel, however, often contains higher quantities of sulphur than gasoline. High levels of sulfur in diesel are harmful for the environment, hence the use of devices that reduce the amount of sulfur in diesel. However, lowering sulfur also reduces the lubricity of the fuel, thus increasing the need for lubricating additives must be added to petro diesel. (see also: Diesel Engine Exhaust Emissions PDF, The Challenging Chemistry of Ultra-low Sulfur Diesel - PDF)
Petro diesel comprises about 75% saturated hydrocarbons, and 25% aromatic hydrocarbons. (see also: Chemical Properties & Composition of Fuel Oils, CDC.gov PDF
Section 7. Diesel Engines
Similar to a gasoline engine, a diesel engine is an internal combustion engine that converts chemical energy present in fuel to mechanical energy that moves pistons up and down inside cylinders. The diesel engine has been the IC engine of choice for various heavy-duty applications for over five decades. In its earliest days it was popular more because it was a considered as the portion of the petroleum crude oil that had previously been discarded as waste during refining of gasoline. Later however, the diesels useful properties its durability, high torque capacity, and fuel efficiency - assured its role in many applications. While the diesel engine is not the engine of choice in US passenger cars (less than 2% of cars in the US are diesel-engine powered), they have much better acceptance in Europe (over 25% of the total market).
Section 8. Biofuels & Gasoline Engines Bio-gasoline?
Biogasoline is a term applied to biomass-based fuels that can be used in fuel engines mainly bioethanol and biomethanol. These can either be blended with gasoline (and used in unmodified engines), or used as a high proportion of the fuel (in flexi-engines). More inputs for ethanol as gasoline fuel is provided in the Ethanol section of the Biodiesel WWW Encyclopedia.
The major fuels that can be considered as biogasoline are:
· Bioethanol: ethanol produced from biomass and/or the biodegradable fraction of waste (see also: What is Bioethanol?, Bio-ethanol from Dept of Energy, Government of USA (PDF), Bioethanol & Blends Properties)
· Biomethanol: methanol produced from biomass and/or the biodegradable fraction of waste (Methanol from Biomass, Competitive with Gasoline IAGS, Bio-methanol from Sugar Beet Pulp PDF, Bio-methanol from Black Liquor - PDF). Biomethanol might become a preferred fuel for fuel cell vehicles because of its high hydrogen content. Biomethanol can be produced from bio-syn-gas, mixtures of H2 and CO derived from biomass. At present, methanol is mostly produced from natural gas (world production 27 mio t/year) with a conversion efficiency of 55%. Biomethanol has in a longer term the economic potential of substituting the methanol derived from natural gas.
· BioETBE (ethyl-tertio-butyl-ether): a fuel produced on the basis of bioethanol (What is ETBE from Wikipedia). Bio-Ethyl Tertiary Butyl Ether is a colourless, flammable, oxygenated hydrocarbon. This biofuel is produced by mixing bioethanol (48% in volume) and tertiary butanol (or bioethanol with iso butylene) and reacting them with heat over a catalyst. This biofuel with an octane rating of 112 can be used in existing gasoline engine without any modification shows excellent performance and environmental benefits replacing aromatics and benzene. It is acceptable for direct refinery blending and for common pipeline transport.
· BioMTBE (methyl-tertio-butyl-ether): a fuel produced on the basis of biomethanol. (MTBE from Wikipedia, MTBE Studies). Bio-MTBE is similar to Bio-ETBE, and is obtained by mixing biomethanol and tertiary butanol.
Section 9. How is Bio-diesel Produced from Plant Oils?
The major problem associated with the use of pure vegetable oils as fuels for diesel engines is caused by high fuel viscosity (Viscosity from Physics Hypertextbook) in compression ignition. The vegetable oils are all highly viscous, with viscosities ranging 1020 times those of no. 2 Diesel fuel. Amongst vegetable oils in the context of viscosity, castor oil is in a class by itself, with a viscosity more than 100 times that of no. 2 Diesel fuel (MSDS of No.2 Diesel Fuel PetroCard). Due to their high viscosity and low volatility, they do not burn completely and form deposits in the fuel injector of diesel engines. Furthermore, acrolein (a highly toxic substance) ( Acrolein from EPA) is formed through thermal decomposition of glycerol (Glycerol from Info Please).
Dilution, micro-emulsification (Emulsions & Emulsification from Wikipedia), pyrolysis ( Pyrolysis Definition from AFR) and transesterification are the four techniques applied to solve the problems encountered with the high fuel viscosity. Amongst the four techniques, chemical conversion of the oil to its corresponding fatty ester is the most promising solution to the high viscosity problem. This process - chemical conversion of the oil to its corresponding fatty ester, and thus biodiesel - is called transesterification.
What is transesterification?
· The process of converting vegetable oil into biodiesel fuel is called transesterification, and is fortunately much less complex than it sounds.
· Transesterification refers to a reaction between an ester (Ester from Wikipedia) of one alcohol and a second alcohol to form an ester of the second alcohol and an alcohol from the original ester, as that of methyl acetate and ethyl alcohol to form ethyl acetate and methyl alcohol ( see also interesterification Interesterification from Cyber Lipid) . Chemically, transesterification means taking a triglyceride molecule or a complex fatty acid, neutralizing the free fatty acids, removing the glycerin and creating an alcohol ester. This is accomplished by mixing methanol with sodium hydroxide to make sodium methoxide (Sodium Methoxide from Great Vista Chemicals, Sodium Methoxide MSDS JT Baker) . This liquid is then mixed into vegetable oil. The entire mixture then settles. Glycerin is left on the bottom and methyl esters, or biodiesel, is left on top. The glycerin can be used to make soap (or any one of 1600 other products) and the methyl esters is washed and filtered.
· Transesterification is not a new process. Scientists E. Duy and J. Patrick conducted it as early as 1853. One of the first uses of transesterified vegetable oil was powering heavy-duty vehicles in South Africa before World War II.
More Links on Transesterification
Biodiesel Manufacturing Equipment
Other Methods of Producing Bio-diesel
Other than transesterification, the other methods that have been considered to reduce the high viscosity of vegetable oils are:
· dilution of 25 parts of vegetable oil with 75 parts of diesel fuel
· microemulsions with short chain alcohols (e.g. ethanol or methanol)
· thermal decomposition, which produces alkanes, alkenes, carboxylic acids and aromatic compounds
· catalytic cracking, which produces alkanes, cycloalkanes and alkylbenzenes
However, when compared with the above, the transesterification process appears to be the best choice, as the physical characteristics of fatty acid esters (biodiesel) are very close to those of diesel fuel, and the process is relatively simple. Furthermore, the methyl or ethyl esters of fatty acids can be burned directly in unmodified diesel engines, with very low deposit
More Bio-diesel Production Links
The following web sites provide more inputs on the various methods to produce bio-diesel, including the transesterification process.
· Biodiesel Basics (PDF)
Section 10. Plant Oils Used for Bio-diesel
A variety of biolipids (Biolipds are lipids from biological sources. Lipids are a class of organic compounds essential for the structure and function of living cells, fats are a subset of lipids, belonging to a subcategory of lipids called triglycerides) can be used to produce biodiesel. The main plants whose oils have been considered as feedstock for bio-fuel are: soybean oil, rapeseed oil, palm oil, sunflower oil, safflower oil & jatropha oil. Others in the contention are mustard, hemp, castor oil, waste vegetable oil, and in some cases, even algae. There is ongoing research into finding more suitable crops and improving oil yield. (Biodiesel A Brief Overview From ATTRA provides a table of oil-bearing plants having potential for biodisel)
A complete list of oils that appear to have the potential for biodiesel is provided below ( in alphabetical order of the plant name)
Algae as Bio-diesel
The production of algae to harvest oil for biodiesel has not been undertaken on a commercial scale, but working feasibility studies have been conducted to arrive at the above yield estimate. In addition to a high yield, this solution does not compete with agriculture for food, requiring neither farmland nor fresh water.
Artichoke & Biodiesel
Artichoke has been only mainly as a forage crop for many years, but in recent years new applications have been discovered. The seeds of the artichoke plant can be used to obtain edible oil, while paper and pulp can be obtained from the stalks.
Artichoke oil is similar to the oils from sunflower and safflower in its composition. The approximate oil composition is as follows: 60% linoleic, 25% oleic, 12% palmitic and 3% stearic acid. While experiments are still on for this crop, initial experiments and analysis appear to show that this crop has potential for producing biodiesel.
· Cynara Cardunculus as an Alternative Crop for Biodiesel Production (MS Word Document)
Canola Oil as Bio-diesel
Canola is a cultivated variety of rapesee, and canola oilseeds are rich in oil content ( 40%). The interest in canola oil as feedstock for biodiesel appears to be gaining ground. A small group of farmers in Australia have started producing biodiesel from canola oil for local use, and a company in North Dakota (USA) in investing significantly to produce biodiesel using canola oil.
Castor Oil as Bio-diesel
Castor oil has quite a few characteristics that can make it a suitable candidate for biodiesel. One aspect that could queer the pitch for castor oil is its viscosity. Castor oil in its straight vegetable oil form is about 100 times as viscous as diesel fuel, and while trans-esterification does reduce the viscosity significantly, it is still being researched whether the final viscosity for castor oil biodiesel is within acceptable limits for use in diesel engines.
Coconut Oil as Biodiesel
Coconut has an oil content of about 70%, and has a yield of about 2500 liters per hectare. The Cetane Number (60) and Iodine Value (10) of coconut oil/copra oil are within acceptable limits for use in diesel engines. Its viscosity after trans-esterification is also in the acceptable range. It thus appears to be a good candidate for biodiesel.
· Possibility of Using Coconut Oil as Fuel Substitute for Diesel Engines (Microsoft PPT Format)
Corn Oil as Bio-diesel
There is a significant interest, especially in the United States, to experiment with corn oil as the feedstock for biodiesel. Till a few years ago, corn was not favoured as a feedstock because the extraction process was not suitable to produce a grade of oil that was suitable enough for producing biodiesel. However newer extraction processes have overcome this problem.
Cottonseed Oil as Biodiesel
Cottonseed oil has energy per unit volume than diesel fuel. This means that more than one gallon of cotton seed oil will be required to replace one gallon of petro-diesel. The current production volumes are quite low ( 0.5 million T per annum in the US) when compared with even reasonable requirements of biodiesel.
Flax Oil as Biodiesel
· The oil from linseed/flax plant can also be considered for biodiesel. Research is ongoing in this area.
Hemp Oil as Bio-diesel
Jatropha Oil as Bio-diesel
Through Jatropha is not as well-known a biodiesel feedstock as is palm oil or soy oil, in India and southeast Asia, the Jatropha tree has been used as a significant fuel source for many years, though use of its oil for biodiesel is quite recent. In these regions, it is also planted for watershed protection and other environmental restoration efforts. Jatropha is a perennial, yielding oil seed for decades after planting. The tree can grow without irrigation in arid conditions where many other biodiesel candidates such as corn and sugar cane could never thrive. Another useful feature of Jatropha is its oil yield the yield is significantly higher than the yields of many other candidates.
· Case Study for Jatropha (PDF)
Jojoba Oil as Biodiesel
While Jojoba is a new entrant in the biodiesel stakes, it has an attraction the jojoba plant can be grown in saline soils, and in desert lands. There are reports that some farmers in Egypt have started cultivating jojoba for the oil to be used as fuel. However, with current inputs and data, it appears that this plant is unlikely to make a significant impact on the overall biodiesel scenario, given the small amounts of cultivation.
Karanj Plant (Pongamia pinnata) as Biodiesel
Karanj, a plant native to India, appears to have good potential for biodiesel. Considered less exotic than Jatropha, there
is a good chance that its oil is cheaper as well. However, only recently has this plant come into the research arena for
biodiesel, and more inputs are awaited.
Kukui Nut Oil as Biodiesel
While it is possible to have the oil from Kukui Nut tree as a biodiesel, it is unlikely that it is a serious candidate since this is not a mainstream crop, and its high price will be a deterrent to its use as fuel
Milk Bush/Pencil Bush (Euphorbia tirucalli) as Biodiesel
The Pencil Bush shrub can grow in arid as well as more mesophytic zones. A large shrub, Euphorbia tirucalli, is used
as a hedge in Brazil. The ability of these plants to grow well in dry regions and on land that are not suitable for growing
food, and the fact that the oil yield from an acre could be comparable to or better than many other biodiesel candidates (
an estimate of oil yield for milk bush/pencil bush is between 10 and 50 barrels of oil per acre, ie., between 25 and 125
barrels per hectare )
Specially bred mustard varieties can produce reasonably high oil yields, and have the added benefit that the meal leftover after the oil has been pressed out can act as an effective and biodegradable pesticide.
Neem Oil as Biodiesel
While it has not yet been produced on a commercial scale, neem oil is being considered for biodiesel, and more research is being done in this area.
Biodiesel from Olive Oil
It has been proven that Olive Oil can produce biodiesel, however, it is unlikely that this crop will be a sustainable
candidate for biodiesel, given the opportunity costs of the use of its oil in other segments, and the cost. One interesting area has been the use of waste olive oil for biodiesel production.
Palm Oil as Bio-diesel
Malaysia and Indonesia are starting pilot-scale production from palm oil. Palm oil so far proved to be efficient as biodiesel.
Peanut Oil as Biodiesel
History tells us that Rudolf Diesel ran his first diesel engine on peanut oil. Even later, during times of fuel shortages, cars and trucks were successfully run on preheated peanut oil. Currently however, peanut oil is used relatively less (when compared to sunflower oil, palm oil or soybean oil) for biodiesel production. One major reason could be the cost.
Radish Oil as Bio-diesel
Wild radish can contain up to 48% oil and its oil is unsuitable for human consumption. This could hence make an interesting biodiesel candidate. Wild radish has adapted itself to be a very resilient weed and possesses a hardy nature with good drought tolerance. However, it is unlikely to become a mainstream biodiesel feedstock.
Rapeseed Oil as Bio-diesel
Rapeseed oil is one of the more prominent oils used for biodiesel preparation. In Europe, rapeseed is the most common base oil used in biodiesel production.
Rice Bran Oil as Bio-diesel
Rice bran oil is a non-conventional, inexpensive and low-grade vegetable oil. Crude rice bran oil is also source of high value added by-products. Thus, if the by-products are derived from the crude rice bran oil and the resultant oil is used as a feedstock for biodiesel, the resulting biodiesel could be quite economical and affordable.
Safflower Oil as Bio-diesel
Quite a number of entities in the United States are experimenting with Safflower oil as biodiesel stock, and there is a opinion among some that safflower oil will make a better candidate than canola oil, which is a relatively more popular feedstock for biodiesel. However, the fact that it is a useful edible oil ( as is canola oil) throws serious doubts about its potential for large scale biodiesel production
Soybean Oil as Bio-diesel
Soybeans are not a very efficient crop solely for the production of biodiesel, but their common use in the United States for food products has led to soybean biodiesel becoming the primary source for biodiesel in that country. Soybean producers have lobbied to increase awareness of soybean biodiesel, expanding the market for their product.
Sunflower Oil as Bio-diesel
Sunflower oil is being tested in quite a few places worldwide for its biodiesel capability. While the chemical properties of the oil lend themselves well for biodiesel manufacture, the high cost of sunflower oil casts doubts on whether it can ever be a significant feedstock for biodiesel production.
Tung Oil as Biodiesel
Research on the use of tung oil for biodiesel is in its initial stages, and more research results and inputs are awaited.
Waste Vegetable Oil as Biodiesel
· Local & Innovative Biodiesel New Feedstock Blending Recipes (PDF) ( see also this (pdf))
Section 11. Ethanol as Fuel
Ethanol is not plant oil, but is an alcohol that is primarily derived from sugarcane molasses, as well as from corn (primarily in the US), but is included here for completeness.
In theory, ethanol can be produced from a range of plants, such as barley, wheat, rice, sorghum, sunflower, potatoes, sugar cane, sugar beet, and corn. Currently however, a large share of ethanol is produced from corn (US) & sugar cane/sugar beet (rest of the world).
As a transportation fuel, ethanol can be used as a total or partial replacement for gasoline. Gasoline containing ten percent ethanol - E10 - is used in many urban areas of the US. Some states promote more widespread use of E10. All vehicles that run on gasoline can use E10 without making changes to their engines.
E85 is an alternative fuel that is 85 percent ethanol and 15 percent gasoline. In order to run on E85, vehicles are specially manufactured as flexible fuel vehicles (FFV). Flexible Fuel Vehicles (Flexible Fuel Vehicle Info from Fuel Economy, from Wikipedia) can use any mixture of ethanol and gasoline up to E85. FFV's have been designed for versatility. They will operate on unleaded gasoline or any mixture of gasoline and ethanol up to an 85 percent blend.
Ethanol, when used as a gasoline component, improves combustion and reduces carbon monoxide emissions.
Brazil (The Brazilian Ethanol Program University of Rio de Janeiro PDF, Ethanol in Brazil - Wikipedia) and Sweden (Why is Ethanol Given Importance over Methanol in Sweden A Research Paper PDF) use significant quantities of ethanol as a fuel. Some Canadian provinces promote ethanol (Ethanol from Canadian Renewable Fuels Association) use as a fuel by offering subsidies. India is in the beginning stages of initiating the use of ethanol as an automotive fuel (Ethanol India). In France, ethanol is produced from grapes that are of insufficient quality for wine production.
Brazil has been one of the pioneering countries in the context of using ethanol in gasoline engines. Brazilian ethanol is made mainly from sugar cane (Sugarcane for Energy PDF). Prompted by the increase in oil prices in the 1970's, Brazil introduced a program to produce ethanol for use in automobiles. A significant percentage of automobiles in Brazil used pure ethanol (100% ethanol). The remaining vehicles use blends of about 20% ethanol with 80% gasoline.
While the main use of ethanol is in gasoline engines, in a few cases ethanol is also used in diesel engines. More research is underway on this concept of Ethanol Diesel E-diesel. E-diesel is usually a a blend of up 15% ethanol, 5% blending additive, and at least 80% petro-diesel. Testing to date has proven that E-diesel can lower particulate emissions by 20% to 30%, reduce sulfur content, and out-perform No. 2 diesel fuel in winter conditions, all without mechanical changes or problems. Additional research is under way to move E-diesel toward commercialization (About E-diesel Fuel from E-diesel Fuel Consortium)
More Ethanol Links & Resources
· Ethanol & Methanol as Bio-fuels for ICEs Envocare, UK (see their Alternative Energy & Renewable Energy Sources Page for more resources)
Ethanol & Biodiesel Compare & Contrast
Section 12. The Economics & Sustainability of Bio-diesel
Biodiesel is, without doubt, a good idea. The real topic that is debated hotly today is whether biodiesel is an economically sustainable idea, given the costs of production, fossil and non-fossil energy spent for producing energy from biodiesel, opportunity costs for the respective plant oils, and the competing fuels (mainly fossil fuels) already available.
The following web resources focus on the economics, cost-benefits & sustainability of bio-fuels in general and biodiesel in particular.
· Interesting Blog Comments on Energy Efficiencies of Biofuel and Bio-diesel Future Pundit (skip the article and see the comments!)
· Biodiesel Experiment (PDF)
· Biodiesel European Overview (PDF)
· Biodiesel Economics in Brazil (PDF)
Biodiesel & Environment
Reducing the Cost of Biodiesel
Section 13 Problems with and Disadvantages of Biodiesel
While biodiesel has its myriad advantages and benefits, there is a flip side as well. This section provides inputs on the various (perceived) disadvantages of biodiesel, as well as problems that have been reported while using biodiesel.
Some of the disadvantages of and problems with biodiesel are:
· It is currently more expensive (see also: Biodiesel Performance, Costs & Use from the Dept of Energy, Govt of USA)
· Disadvantages of using biodiesel produced from agricultural crops involve additional land use, as land area is taken up and various agricultural inputs with their environmental effects are inevitable. Switching to biodiesel on a large scale requires considerable use of our arable area. Even modest usages of biodiesel would consume almost all cropland in some countries in Europe! If the same thing is to happen all over the world, the impact on global food supply could be a major concern, and could make some countries being net importers of food products, from their current status of net exporters! It Could so happen that most lands on the planet are deployed to produce food for cars, not people! ( see also: Biodiesel & Deforestation, Amount of Biodiesel That Could be Produced from Available Land in the UK An Estimate)
· It gives out more nitrogen oxide emissions (Nitrogen oxide emissions from biodiesel blends could possibly be reduced by blending with kerosene or Fischer-Tropsch diesel) (NOx & Biodiesel Journey to Forever, Study Shows NOx Emissions Reduction in Biodiesel with Additives PDF)
· Transportation & storage of biodiesel require special management. Some properties of biodiesel make it undesirable for use at high concentrations. For example, pure biodiesel doesn't flow well at low temperatures, which can cause problems for customers with outdoor storage tanks in colder climates. A related disadvantage is that biodiesel, because of its nature, cant be transported in pipelines. It has to be transported by truck or rail, which increases the cost.
· Biodiesel is less suitable for use in low temperatures, than petrodiesel. The cloud point is the temperature at which a sample of the fuel starts to appear cloudy, indicating that wax crystals have begun to form. At even lower temperatures, the fuel becomes a gel that cannot be pumped. The pour point is the temperature below which the fuel will not flow. As the cloud and pour points for biodiesel are higher than those for petroleum diesel, the performance of biodiesel in cold conditions is markedly worse than that of petroleum diesel. At low temperatures, diesel fuel forms wax crystals, which can clog fuel lines and filters in a vehicles fuel system. Vehicles running on biodiesel blends may therefore exhibit more drivability problems at less severe winter temperatures than do vehicles running on petroleum diesel.
· Another disadvantage of biodiesel is that it tends to reduce fuel economy. Energy efficiency is the percentage of the fuels thermal energy that is delivered as engine output, and biodiesel has shown no significant effect on the energy efficiency of any test engine. The energy content per gallon of biodiesel is approximately 11 percent lower than that of petroleum diesel. Vehicles running on biodiesel are therefore expected to achieve about 10% fewer miles per gallon of fuel than petrodiesel.
· There have been a few concerns regarding biodiesels impact on engine durability
· Biodiesel has excellent solvent properties. Hence, any deposits in the filters and in the delivery systems may be dissolved by biodiesel and result in need for replacement of the filters. Petroleum diesel forms deposits in vehicular fuel systems, and because biodiesel can loosen those deposits, they can migrate and clog fuel lines and filters.
· The solvent property of biodiesel could also cause other fuel-system problems. Biodiesel may be incompatible with the seals used in the fuel systems of older vehicles and machinery, necessitating the replacement of those parts if biodiesel blends are used.
More Links on Biodiesel Disadvantages
Section 14. Biodiesel Case Studies
· The Development of Biodiesel (PDF)
· Biodiesel Fleet Use & Benefits (PDF)
· Study of Biodiesel from Tallow (PDF)
· Biofuels for CHP in Buildings (PDF)
Biodiesel in North America
· Biodiesel for Arkansas (PDF)
· Seattle Biodiesel Set to Expand (PDF)
· Biobus Project, Canada (PDF)
· Biodiesel Made in Manitoba (PDF)
Biodiesel in Europe
Biodiesel in South America
Biodiesel Case Studies in Other Geographies
France, Italy, Japan, Korea, Australia, India, China, Russia, Canada, Brazil, Argentina, South Africa, Middle East, Spain, UK, Germany, Scandinavia, Benelux, Mexico, Indonesia, Thailand, Turkey, Philippines
Section 15. Biodiesel Forums, Discussion Boards & Blogs
· The DieselStop Forums (Use the Biofuels Forum Link)
Section 16. Bio-diesel Research & Future Trends
The following web resources provide inputs on the various research activities happening in the biodiesel front:
Section 17. Bio-diesel Links & Directory Pages
These page provide (similar to ours) links to a large number of biodiesel resources on the web. We hope you find these useful
Section 18. Articles & Opinions
Section 19. Biodiesel - Questions & More Questions
Can animal fat be used as biodiesel?
How long would petro-diesel/gasoline last?
· Long Term World Oil Supply Dept of Energy, Govt of USA ( see also here)
What are the other alternatives to biodiesel?
What are the key disadvantages of biodiesel?
What is the cost of biodiesel vis a vis petro diesel?
Can I make biodiesel at home?
What is the experience of biodiesel made from waste oil?
How much biodiesel would be required to completely replace petro-diesel? What % of this is available currently?
The current world consumption of petro-fuels is about 12 Million Tons per day = about 5 billion T per annum. Since the energy provided by biodiesel is slightly (about 10%) lower than that of petro-fuels, the world would require about 5.5 billion T of bio-diesel to completely replace petro-diesel, at the current levels of consumption. The total world production of vegetable oils was only about 0.06 billion T in 2005. That is, the total production of vegetable oil in the world is just one-hundredth of what will be required for complete replacement. It is easy to see that it very early days for biodiesel. (see also: What is Biodiesel from Becon, Iowa State University)
What are the likely scenarios with regard to biodiesel usage in future?
· Managing Future Fuels Complexity (PDF)
What is the chemical structure of biodiesel?
Can biodiesel be produced at lower costs at much higher capacities economies of scale?
What are the various forms of bio-energy?
Are there any changes I should make to my diesel engine in order to use biodiesel?
Biodiesel can be used without any changes to a diesel engine.
Are there more biodiesel FAQs on the web?
Are there alternative methods of biodiesel processing/manufacture currently being contemplated?
Transesterification is the main process that is used to make biodiesel from plant and vegetable oils. The alternative methods (to transesterification) are:
· dilution of 25 parts of vegetable oil with 75 parts of diesel fuel
· microemulsions with short chain alcohols (e.g. ethanol or methanol)
· thermal decomposition, which produces alkanes, alkenes, carboxylic acids and aromatic compounds
· catalytic cracking, which produces alkanes, cycloalkanes and alkylbenzenes
Tell me more about Biodiesel blends with petro-diesel/gasoline?
Are there biodiesel glossaries online?
What are the legacy petro companies response to biodiesel?
Which are the major companies foraying into biodiesel?
What are the market segments for biodiesel?
Market Segment - Electricity Generation
Market Segment - Farming
Market Segment - Fleets
Market Segment - Heating Oil
Market Segment - Marine
Are there Biodiesel publications & magazines online?
Can Biodiesel help mitigate global warming?
Section 20. Biodiesel Breakthroughs
The following links provide inputs on the recent breakthroughs in the field of biodiesel
Section 21. Biodiesel Links A-Z
Section 22. Biodiesel Data & Stats
Biodiesels has physical properties very similar to conventional diesel (source: Alternative Fuels Data Center, Department of Energy, Govt of USA)
Typical Extraction Yields of Oil from Oilseeds
(Kg of oil from 100 Kg of oilseed)
Yield of Various Plant Oils
Crop Oil in Liters per hectare
Some Gasoline/Petrol & Diesel Facts:
Sulfur Content: 0.05 percent maximum allowed for diesel
Density: 7.076 lb/gal (diesel) 6.15 lb/gal (gasoline)
Heating Values: Diesel: 19300 Btu/lb (136,567 Btu/gal); Gasoline: 20300 Btu/lb (124,845 Btu/gal) - Approximately 45-47 GJ/T
American standard testing methods (ASTM) tests and limits for Diesel fuels
Test ASTM Test No. ASTM limits for no. 2 Diesel fuel
Carbon residue (wt.%) D 524 0.35 % max.
Cetane no. D 613 40 min.
Distillation range (K) D 86 555611
Flash point (K) D 93 325 min.
Higher heating value (MJ kg_1) D 2015 45.2 min.
Viscosity (mm2 s_1) D 445 1.94.1
Kinematic Viscosity Specs & Standards
Specifications: (viscosities in mm2/s)
Europe Petrodiesel: 2.04.5
Europe Biodiesel : 3.55.0
US specification of viscosity for low-sulfur No.2 diesel fuel: 1.9-4.1 mm2/s (this is the fuel that is biodiesel is most often compared to)
US Specification for No. 1 diesel fuel is 1.32.4 mm2/s.
Most alkyl esters of vegetable oils have kinematic viscosities less than 5.0 mm2/s.
Section 23. Biofuel Reference
Classes of Biofuels
There are many forms of solid biomass that are combustible as a fuel such as:
· Straw and other dried plants
· Animal waste such as poultry droppings or cattle dung
· Crops such as maize, rice, soybean, peanut and cotton (usually just the husks or shells) & sugarcane- or agave-derived bagasse.
There are also a number of liquid forms of biomass that can be used as a fuel:
· Ethanol usually produced from sugarcane, also from corn
· Methanol, which is currently produced from natural gas, can also be produced from biomass. The methanol economy is an interesting alternative to the hydrogen economy
· Butanol, formed by A.B.E. fermentation (Acetone, Butanol Ethanol) and experimental modifications of the ABE process show potentially high net energy gains. Butanol can be burned "straight" in existing gasoline engines (without modification to the engine or car), produces more energy and is less corrosive and less water soluble than ethanol, and can be distributed via existing infrastructures.
· Biologically produced oils (bio-oils) can be used in diesel engines
· Straight vegetable oil (SVO)
· Waste vegetable oil (WVO)
· Biodiesel obtained from transesterification of animal fats and vegetable oil, directly usable in petroleum diesel engines
· Oils produced from various wastes
· Thermal depolymerization from waste materials can extract methane and oil similar to petroleum
· Methane and oils are being extracted from landfill wells and leachate in test sites
· Bio-methane produced by the natural decay of garbage or agricultural manure can be collected for use as fuel
· Wood gas can be extracted from wood and used in petrol engines.
· Hydrogen can be produced in water electrolysis or, less ecologically, by cracking any hydrocarbon fuel in a reformer, some fermentation processes also produce hydrogen, such as A.B.E. fermentation
· Gasification, that produces carbon monoxide.
The specific energy densities ( in MJ/kg) of various fuels
· Wood Fuel 16-21
· Methanol 20-23
· Ethanol 24-27
· Butanol - 36
· Biodiesel - 38
· Methane 55-56
· Hydrogen 120-140
Fossil Fuels (for comparison)
· Coal 29-34
Section 24. Fossil Fuel Energy Limitations & Crises