Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations KootK on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

need the chemical composition of diesel 3

Status
Not open for further replies.

960521

Petroleum
Jul 11, 2006
5
Hello everybody,

I have made my best effort to gather information regarding to the chemical composition of diesel, but without result now. I know the composition is different from plant to plant.I just need one or two as an example.

can someone give me some comment?
 
Replies continue below

Recommended for you

Review ASTM D 975, the standard specification for Diesel Fuel Oils. This covers the physical properties of Diesel product. Also review ASTM D396, the Standard Specification for Fuel Oils.

Crude oils vary widely in composition. Diesel and kerosine are among the side draws from the first separation column in a refinery the atmospheric distillation tower. Many compounds exist. Look for crude oil distillation to find a range of compounds that in the Diesel range. Also look for number 2 fuel oil.
 
Thanks JL Seaqull.

I need the chemical composition of the diesel, like the weight percent of butane,pentane, benzene,toluene,etc..the ASTM can't provid it.
 
I dont know if it helps but diesel is often given a cetane number the perfect diesel is supposed to have around the same carbon atoms and properties as cetane. Of course the perfect diesel doesnt exist but if you just want some rough and ready ideas you could use cetane.
 
Thanks all of you who concern my question. What I want to do is evaluate the diverse effects of the diesel to the environment. So I want to know the approximately compounds and their percentage in the diesel, after making clear every compound’s effect then, get the diesel’s effects to the environment. One or two sample as represent is enough for me. Is anybody know the chemical composition of diesel?
 
I suppose nobody will answer your question. What do you mean by diesel? If you are speaking about petroleum car diesel combustible you have to get some samples from several commercial distributors and analyse it in a laboratory in what it concerns contaminants, hydrocarbon content, and additives. Diesel composition as well as contaminants, are influenced by crude origin and varies from one crude mix to another.

Generally speaking Diesel fuels predominantly contain a mixture of C10 through C19 hydrocarbons, which include approximately 64% aliphatic hydrocarbons, l-2% olefin hydrocarbons, and 35% aromatic hydrocarbons in that proportions are included contaminants

Luis

 
Thanks BigInch,the website shows the cetane number,heat combustion, etc.but no percentage of the compounds.
 
Figure 4-2
Tpical Carbon Number Distribution - No2 Diesel

>>> Mass Percentages<<<<

of each carbon chain are shown on the graph. I didn't add them up, but it looks like it totals 100% to me.


====================more info============================
Data Columns headed as follows, Name, Class, Carbon_Number, Density20ºC_g/cm2, Heat_Combustion_25ºC_Btu/lb, Net Heat of Cobustion_25ºC_Btu/Gal

Naphthalene Aromatic 10 1.175 16,704 163,800
Tetralin Aromatic 10 0.9695 17,422 140,960
1, 3-Diethylbenzene Aromatic 10 0.8639 17,792 128,270
n-Butylcyclohexane Naphthene 10 0.7992 18,666 124,500
n-Pentylcyclopentane Naphthene 10 0.7912 18,738 123,720
Decane n-Paraffin 10 0.7301 19,018 115,880
2, 2-Dimethyloctane Isoparaffin 10 0.7245 18,979 114,750
Anthracene Aromatic 14 1.251 16,514 172,410
n-Nonylbenzene Aromatic 15 0.8558 18,120 129,410
n-Nonylcyclohexane Naphthene 15 0.816 18,672 127,150
n-Decylcyclopentane Naphthene 15 0.811 18,721 126,710
n-Pentadecane n-Paraffin 15 0.7684 18,908 121,250
n-Tetradecylbenzene Aromatic 20 0.8549 18,264 130,310
n-Tetradecylcyclohexane Naphthene 20 0.825 18,678 128,590
n-Pentadecylcyclopentane Naphthene 20 0.8213 18,712 128,260
Eicosane n-Paraffin 20 0.7843 18,853 123,400

That's all I can give you.

 
I'm not sure if the mass percentages quoted will answer your question. The piona analysis only tells you that burning diesel gives CO2 and H2O, which you probably already knew.
For environmental effects you may be more interested in sulfur and other ingredients at sub % or even ppm level. I'm sure this must have been studied a zillion times already and you should be able to google up results instead of redoing the exercise.
 
21121956 (Mechanical)
where's the chemicals? These are what I would call mostly physical attributes.



Could be that previous data concerning sulfur may have recently changed or will change with the new low sulfur limits.

 

960521, the Chevron link brought by BigInch, has a graph (fig 4-3) under Diesel Fuel Chemistry showing % for each carbon number.
 
960251:

You are not asking the correct question. As pointed out by Epoisses, all you can do with an analysis of the diesel is to perform some stoichiometric combustion calculations which will only tell you that burning the diesel results in the formation of carbon dioxide, water vapor, some sulfur dioxide and some nitrogen oxides.

For a study of the environmental effects of burning diesel oil in a fired heater, an automobile or other diesel fueled equipment you should be asking what hazardous trace compounds are formed. You should read this U.S. EPA report:

EPA/600/8-90/057F, May 2002, "Health Assessment Document for Diesel Engine Exhaust"

It can be downloaded online at:


Milton Beychok
(Visit me at www.air-dispersion.com)
.
 
thanks mbeychok.I'm afraid you don't know what i am doing.

when transport, storage of the oil(including diesel, gasoline, etc.), there exist leakage of the oil, the leakaged oil can infiltrate to the soil, and then contaminate the soil, surface water and groundwater. In some sense, it is more dangerous than the exhausted gases. So I need to know the original compounds of the diesel rather than the burning results.
 
I think BigInchs mass percentages post may be the most comprehensive quantitative component analysis you may get your hands on. I tries to do a similar exercise with Bitumen a while back and just gave up in the end. Too many heavy and exotic hydrocarbons to effectively analyse.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor