A biofuel is a fuel that contains energy and is derived from plants or biomass.

There are 3 main types of biofuel: Bioethanol, biodiesel, and biojet fuel. Bioethanol is used in engines that burn gasoline, like most cars. Biodiesel is used in engines that burn diesel fuel, like large trucks and tractors. Biojet fuel is used in planes.

A biodiesel is a vegetable oil - or animal fat-based fuel consisting of long chains & containing alkyl (methyl or ethyl or propyl) esters.

Bioethanol is an alcohol made by fermentation, mostly from carbohydrates produced in plants as sugar or starch.

Biojet fuel is made from vegetable oils, sugars, animal fats and even waste biomass, and can be used in existing aviation jet engines without modification.

Jatropha oil is  suitable for conversion to jet fuel. This biojet fuel has received wide acceptance from the airline industry.

A biofuel is a fuel that contains energy and is derived from plants or biomass.

There are 3 main types of biofuel: Bioethanol, biodiesel, and biojet fuel. Bioethanol is used in engines that burn gasoline, like most cars. Biodiesel is used in engines that burn diesel fuel, like large trucks and tractors. Biojet fuel is used in planes.

A biodiesel is a vegetable oil - or animal fat-based fuel consisting of long chains & containing alkyl (methyl or ethyl or propyl) esters.

Bioethanol is an alcohol made by fermentation, mostly from carbohydrates produced in plants as sugar or starch.

Biojet fuel is made from vegetable oils, sugars, animal fats and even waste biomass, and can be used in existing aviation jet engines without modification.

Jatropha oil is  suitable for conversion to jet fuel. This biojet fuel has received wide acceptance from the airline industry.

Jatropha oil can also be used -after transesterification - as biodiesel as well.

As Nizar wrote, bioethanol chemcially is ethanol, can be made from sugars by fermentation.

Biodiesel is a mixture of  estesr of long chain fatty acids, generally a mixture of methyl esters of C16-C22 saturated/unsaturated =0-3 double bond containing ) fatty acids.

 These fattya acids are in jatropha oil in triglyceride form, thus it has to be transesterified before using as biodiesel. .   

Additional comments:

Energy is the capacity to promote change: in any of its many forms, such as thermal, mechanical, electrical and chemical, energy always represents the capacity to cause transformations, either through natural or man-made processes. Chemical energy is energy generated through chemical reactions, by which molecules are converted into products, usually releasing heat.

Bioenergy is one special form of chemical energy. It includes any kind chemical energy accumulated through recent photosynthetic processes. In general, natural resources that contain bioenergy and can be processed to obtain more complex energy carriers suitable for end-uses are called biomass.

Examples of sources of bioenergy include biofuels such as wood and sawmill waste, charcoal, biogas resulting from the anaerobic decomposition of organic waste and other farming waste, as well as liquid biofuels, such as bioethanol (by fermentation from sugar, starch or hydrolyzed cellulosic feedstock), biodiesel (by transesterification of fatty feedstock), and biokerosene for aviation (by several paths and feedstocks), and bioelectricity, generated by burning fuels such as bagasse and wood.

References probably useful:

1. Sugarcane-based ethanol: energy for sustainable development (available free in Researchgate and http://www.bioetanoldecana.org), see first chapter.

2. FAO Unified Bioenergy Terminology (UBET) 2004 (ftp://ftp.fao.org/docrep/fao/007/j4504e/j4504e00.pdf)

3. Flightpath to aviation biofuels in Brazil: action plan (http://www.fapesp.br/publicacoes/flightpath-to-aviation-biofuels-in-brazil-action-plan.pdf)

ftp://ftp.fao.org/docrep/fao/007/j4504e/j4504e00.pdf)

http://www.fapesp.br/publicacoes/flightpath-to-aviation-biofuels-in-brazil-action-plan.pdf

Dear Prof Luiz

Thanks for prompt reply ad valuable data . As, I hope collaborate with you i ear future

by definition biodiesel is a mixture of C14-C22 fatty acid methyl esters (hence: FAME), bio-jet is a severely hydrotreated alkane mixture of feedstock varieties of biologically origin 

Sir, it depends on ignition type.

For engine with spark ignition system we can use ethanol/bioethanol or other alcohol and gasoline and/or mixture of mentioned.

Engines with self ignition system (Diesel/Cummins mostly) burn FAME/FAAE (Fatty Acid Methyl/Ethyl Esters) and Diesel Oil and/or mixture of mentioned.

Engines for aircraft - depends if it is piston engine or jet engine. Piston engine is type of spark ignition - mentioned above. For jet engine You can use FAME/FAAE or other type of biodiesel - but no pure biofuel, usually as additive.

There is a lot of problems with biofuel use because of materials compatibility,

biodegradability, instability of properties during storage, differ cetane/octane number, some other emissions, etc.

What I missed above is the type of engine wchich may burn all type of fuels including solid fuel (as coal, wood) and all type of liquids. I thinking about steam engine and/or Stirling engine. Both with external combustion system.

Hope it helps!

Dear Dr Janusz Rebis '

Thanks for your valuable information and looking forward to know more from you in the future and get cooperate with you in coming years

Dear Nabil Mustafa,

I will just add a comment on what has already been answered by our colleagues. Ethanol (or Bio-ethanol) can be used in any spark ignition engine (Otto Cycle) and has been used in mixtures with gasoline for quite sometime all over the world for it enhances the octane number (anti-knock property) of gasoline and it is also a fuel on its own. In Brazil, we have been using ethanol as fuel since 1979 and, since 2002, we have been using flex-fuel vehicles that can run solely on gasoline, solely on ethanol or on any mixture of the two. The majority of the ethanol produced in Brazil is by fermentation of sugarcane molasses, utilizing Saccharomyces cerevisae yeasts.

Biodiesel is comprised of fatty acid alkyl esters and it is usually produced by transesterification of vegetable oils or tallow with a short chain alcohol (either methanol or ethanol)min the presence of a catalyst (most commonly sodium methoxide). Biodiesel can be used in compression ignition engines (Diesel Cycle) without the need for any modification to the engine. It can be used as such because the properties of biodiesel are quite similar to those of petroleum diesel. The key is the number of carbons (usually in the range of 12 to 22) that matches the number of carbons that comprises the hydrocarbon molecules in petroleum diesel. Because in biodiesel all carbon chains are linear and they contain oxygen (that is not present at significant amounts in petroleu diesel), biodiesel presents higher cetane numbers than petroleum Diesel.

Considering what was commented on biodiesel, a bio-jet fuel would have to be comprised of molecules that would have the same number of carbons than those in kerosene aviation fuel (produced from petroleum). However, in the case of jet fuel, it is not as simple as biodiesel, because the fuel has to present other properties that cannot be easily met by simply esterifying fatty acids with number of carbons matching those of kerosene. One of the major problems is that the fuel has to withstand very low temperatures without freezing. Fatty acids that do not present double bonds are usually solid at ambient pressure and temperature. Thus, it is a bit more complicated to achieve high quality jet biofuel...

thanks for your valuable information Dr Leandro Soares 

However can we used oiive pomace in bio-fuel production?

"However can we used oiive pomace in bio-fuel production?" I think so.

Hi Nabil,

Essentially, a fuel to be used as “jet fuel” has to accomplish several quality criteria that has been established on standards as ASTM 1655 and ASTM D7566. No more, no less.

You can find helpfully information on the following publications among a lot many others; as a matter of fact, jatropha oil has been studied as possible jet fuel component:

  * IATA 2013 Report on Alternative Fuels: www.iata.org/publications/documents/2013-report-alternative-fuels.pdf

  * ASEAN Engineering Journal, Part A, Vol. 4, No. 1, March 2014: http://www.seed-net.org/download/AEJ_Vol_4_No_1_REVISED_2.pdf

Please review here publications regarding jatropha oil on reference part (page. 27) of “REVIEW OF TYPICAL BIOFUEL FOR AVIATION ALTERNATIVE FUEL PURPOSES” paper

  * Standard Specification for Aviation Turbine Fuels, ASTM D1655

  * Standard Specification for Aviation Turbine Fuel Containing Synthesized       Hydrocarbons, ASTM D7566

Bye,

www.iata.org/publications/documents/2013-report-alternative-fuels.pdf

http://www.seed-net.org/download/AEJ_Vol_4_No_1_REVISED_2.pdf

Hi again Nabil,

Please review the following report:

 * ICAO ENVIRONMENTAL REPORT 2010:  http://www.icao.int/environmental-protection/Documents/EnvironmentReport-2010/ENV_Report_2010.pdf

Bye,

http://www.icao.int/environmental-protection/Documents/EnvironmentReport-2010/ENV_Report_2010.pdf

Short answer:

bio-jet = biofuel for aircraft, but only for jet engines - not for piston ones.

bio-ethanol = vodka w/o water (ethyl alcohol + water less than 1%) made of part of renewable resources - may be use for aircraft (find dr Shauk or this masters: https://baylor-ir.tdl.org/baylor-ir/bitstream/handle/2104/5133/Grazia_Zanin_Masters.pdf?sequence=1); this is fuel for spark ignition engines.

bio-diesel = fuel for self ignition engines made of renewable resources such as rapeseed oil, jathtopia, palm oil, algee.

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How  can decide the extracted oil from Jatropha can be useful to be bio-jet or bio-diesel? Answer is not so easy. Believe it (in most) depends on what climate you got and production of what type of biofuel is less expensive and for which one fuel government will pay more. Political aspects are too. For example in EU someone told that rapeseed oil (which in Poland is most commonly produced) is food and use it as fuel should be prohibited. Of course, we have a lot of great 'farmland' and production of biofuel has no impact on 'public hunger' but economics of EU tell: prohibit to force them all to buy new technologies from France and Germany. Another aspect is materials compatibility - not only of engines but these from which storage and distribution system were made. I do not know which (jatropha of FAME/FAEE) biodiesel is less harmfull for parts of engines and other devices which has contact with this fuel.

Hi,

Be careful here when some one justify the biofuel production in the way of "no impact on public -people- hunger". Very easy: all the resourses comprised on the production a biofuel must be directed to produce food, that means, over every others, the land and the water....

Thanks,

Dear Raul and colleagues,

I agree with you; it is not correct to say that biofuels production do not affect food availability, as it is also wrong to say that biofuels production always affect food availability. But, what is the impact? The key information here the amount of resources (good land, water, labor, money, etc.) required and the effective availability of resources. So, it is a big mistake to assume that "biofuel should be made of non edible feedstock, in order to not harm food supply...", because in some extension biomass production always require inputs, whatever, food, fiber, flowers, energy, etc. But, in fact, in the last decades, food supply per capita have been increasing globally, and hence, today obesity is more worrying than starvation.

I think that there is a large room for increase bioenergy production in developing countries, most of them in wet tropical regions with large availability of land. To give you an example, many countries have an important share of their territory as very low efficiency pastures, a small fraction of this area would be enough to produce relevant amounts of biofuels, generating jobs and income, reducing the burden of importing fossil fuels and, as secondary effect, reducing GHG emissions.

If you and colleagues are interested in this topic, I would suggest some references:

Bioenergy & Sustainability: bridging the gaps, edited by Souza, GM Victoria, RL Joly CA and Verdade, LM, Scientific Committee on Problems of the Environment, SCOPE 72, Paris, 2015

This book (772 pg) is a collective effort with contributions from 137 researchers of 82 institutions in 24 countries, addressing and discussing the main questions related to bioenergy and sustainability. You can download it free in: http://bioenfapesp.org/scopebioenergy/index.php.

In the LACAf project we are exploring exactly these questions and evaluating the sustainable potential of sugarcane bioenergy in L America and Southern Africa. The two papers below present, among other aspects, the potential of producing bioenergy using just 1% of pasture land in Latin American and Southern Africa countries. Maybe you will be surprised about how much renewable energy could be produced in these conditions.

Potential of Sugarcane in Modern Energy Development in Southern Africa, Frontiers in Energy Research 4, December 2016, DOI 10.3389/fenrg.2016.00039

Sugarcane can afford a cleaner energy profile in Latin America & Caribbean, Renewable Energy (Elsevier) January 2018, DOI 10.1016/j.renene.2018.01.024

All the best,

Luiz Horta Nogueira

All the three biofuels serve for the same purpose but in different of operation.

It all starts with a simple classification of a feedstock into lipid (oil) content & non lipid content.

Biodiesel is the transesterified product of the oil (lipid) extracted from the feedstock. Its usually a long chain fatty acid alkyl esters with good cetane number.

Bioethanol is the fermented product of the non lipid content ( residue after oil extract) ,where glucose and sucrose breakdown and get converted into ethanol.

Biojetfuel is the thermally cracked product of the oil(lipid) extracted or biodiesel produced from the feedstock. Its usually a short chain or medium chain hydrocarbon with good octane number.

Good Luck Sir