Diesel vs. Gasoline - why one preferred over another??

Don Stauffer wrote:

> Steve wrote:
>
>> y_p_w wrote:
>>
>>> Steve wrote:
>>>
>>>> Its clear exhaust gas still SMELLS like a Diesel, though.
>>>
>>>
>>>
>>>
>>> Wouldn't that have more to do with the higher-sulfur diesel fuel
>>> sold in the US? I know the amount of sulfur has gone down in
>>> recent years though.
>>
>>
>>
>> Possible, but doubtful. Its not a sulfurous smell at all. I guess
>> we'll find out when we start getting low-sulfur fuel similar to what
>> Europe gets now.
>>
>>
>>
> There are many different sulphur compounds possible in an engine
> exhaust. Each smells different. Most people associate a "sulphur
> smell" with hydrogen sulfide. However, there are many sulphur compounds
> in exhausts that smell nothing like H2S.

Like I said, we'll see when true low-sulfur fuel gets widespread here. I
personally think it'll still smell the same- yes there are different
sulfur compounds, but the vast majority of them do have a recognizable
sulfuroous smell. For example, its perfectly easy to tell sulfur dioxide
from hydrogen sulphide, but the smells are similar enough to both be
recognizable as sulphur compounds.

Mark Levitski wrote:
> Know nothing of cars (electrical person) - used public transportation all my
> life.
>
> Why is that 95% of passenger cars in the US are gasoline, yet diesel used in
> much of Europe? I read somewhere diesel is more efficient, plus unlike gas
> engine even UNMODIFIED diesel unit can run on "biofuels" (filtered cooking,
> etc. natural oils), so why diesel not dominating the market? I thought it's
> even cheaper?
>
> However, my primary question is:
> Is it true Diesel engine causes a much worse pollution, especiall;y
> carcerogenic (CANCER-causing) exhaust?? If so that would answer questions
> above. But again I thought new diesels burn as clean as gasoline?
>
> I wouldn't bother with all this, if it wasn't for the growing interest in
> biofuels and several people said "cooking oil", etc. works ONLY in diesel
> engines, it will NOT run in gasoline - dont even try.
>
> Thanks for your time, I might answer your electrical questions in the
> future, who knows... so it's not a waste of your time.
>
>
Both Diesel AND alcohol exhausts have aromatics in them. Some aromatics
can be carcinogenic, but I have read mixed comments on whether these
specific ones are, at least in reasonable quantities.

Al Haunts wrote:
>>I am in the fix of a state intending to move to 20% ethanol. Even it it
>>WILL work in cars, mfgs will void warranty. I can't afford to buy a new
>>car that does not have a warranty, so I am opposed to this move until
>>Detroit says it is okay. Yet my one car has almost 90,000, the other
>>110,000 miles, so I will be needing new cars soon.
>
>
> Biggest problem with ethanol is the fact it only has about half the
> energy of gasoline by volume. 20% equals 10% worse fuel mileage.
> They should title legislation requiring ethanol to be added to gas the
> "Corn Farmers Endowment Act" 'cause that's the group who really
> benefit.
>
> Regards, Al.
>
Anyone know how many BTUs it takes to make a gallon of ethanol?

I guess I could assume that fermentation creates about 5% alcohol, so
one would need to start with about 20 gallons of alcohol and water, and
raise those 20 to BP. But sure would like to have a better figure.