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6. Fuel Refinery
Chemistry
Back to: Start
Dr. John Sinfelt, Inventor
Through a
lifetime of study of small clusters of metal
atoms - metallic clusters, Dr. John Sinfelt paved
the way for efficient conversion of petroleum
into useful fuels. Consider the before and after
situation regarding TEL. Before its removal, oil
companies wanted to have high quality fuels that
contained BTX components, but they could make up
deficiencies in fuel performance by the addition
of TEL.
But after TEL
was no longer allowed, fuels HAD to be better.
And the amount of BTX components that would be
necessary for the maintenance of fuel quality
would be much larger than before the elimination
of TEL.
That would
require the costly construction of many new
refinery operations to "reform" the
fuel to high BTX levels.
But there is
where Dr. Sinfelt's basic research paid off. He
learned that selected metallic clusters catalyzed
breaking of C-C and C-H bonds and dramatically
increased the rate of chemical reactions that
formed the BTX components. Dr. Sinfelt's timely
inventions allowed much greater capacity amounts
of reformulated fuel to be made in the same
facility.
Dr. Sinfelt, a
1954 graduate of the University of Illinois in
Physical Chemistry, based his success in the
mathematical representation of the processes he
studied. He could observe the results of an
experiment conducted under specific experimental
conditions in a specially designed reactor that
mimiced, on a small scale, the refinery itself.
But his greatest understanding came when he used
the equations and symbols of mathematics to
relate his observations to the known laws of
kinetics and thermodynamics. If we read Dr.
Sinfelts' published works, we are reading a
mathematical interpretation and the successful
predictions that emanated from this symbolic
understanding.
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The TEL phase out
meant that other ways would have to be found to boost
octane levels. Ironically, most of the choices are the
same as those Charles Kettering and the GM research team
considered in the 1920s.
| Petroleum Modifications:
The first and most obvious way to make up the
octane deficiency after a lead phase out was to
further change refinery
operations and increase the amount of
aromatic constituents in the gasoline. BTX
compounds (benzene, toluene and xylene) increased
to more than 20% in the gasoline in the 1970's. Domestic
oil companies have had a century-long history of
research to control the product that comes from
refining of crude oil. Processes such as
"Platforming", Powerforming" and
"Ultraforming" were introduced long
before the lead phase-out in order to improve the
quality of the fuels by introducing branched
chain and BTX compounds.6 – 1990
period.
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This is very much akin to simply
adding benzene, as T.A. Boyd recommended in 1922. Its
health effects are not as severe as lead, but they are
significant, according to a World Bank study. While 5,000
Americans died every year as a result of heart disease
from lead, some 47 people developed cancer from the use
of benzene as a lead replacement. “The health
impacts of aromatics are several orders of magnitude less
than that of lead,” the World Bank told a Nation
magazine reporter.
Today's hydrocarbon fuel composition
depends to a great extent on the catalytic processes invented by
Dr. John Sinfelt at Esso Research in the 1960's.
Additives: Tertiary
Butyl Alcohol, TBA( 2-Methyl-2-Propanol), with an octane
number of 108, is an old stand by in the Sunoco system,
and its use was more widespread after 1976. However, TBA
had supply problems that prevented its use in treating
the total production of gasoline.
One newer alternative is MTBE
(Methyl Tertiary Butyl Ether, also known as
2-methoxy-2-methylpropane). However, MTBE caused serious
problems in water supplies, as we will see in section 26.
Finally, the oldest alternative
fuel, ethanol, is being produced from farm products in
the U.S. at around one percent of the total gasoline
supply, and is routinely blended at 10 percent ratios
with gasoline. Most sales are in the Midwest and in
cities where winter smog is improved by adding an
oxygenated fuel.
In the last ten years, gasoline
overall composition has been changed (from that of
gasoline sold as recently as 1990) to 1) include
oxygenates; 2) reduce the content of olefinsand aromatics
and volatile components, and 3) reduce the content
ofheavy hydrocarbons to meet performance specification
ozone-forming tendency and for release of toxic
substances into the air from both evaporation and
tailpipe emissions.
Gasoline composition is regional and
seasonal. Winter gasolines must have higher volatility
than those used in the summer. State and local laws
preclude or include certain compositions. You can find
one summary of the complex gasoline compositions at http://www.eia.doe.gov/emeu/steo/pub/special/rfg4.html#Summary
You might go on to fuel refinery chemistry or the
reformulation process.
As MEH drove up
I-70 in Colorado, west of Denver a couple of
years ago, his 1993 Infiniti suddenly stalled
out. he was at the entrance to the Eisenhower
Tunnel, at an elevation of nearly 11,000 feet.
Eisenhower Tunnel as You Watch
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That day was a brilliant,
warm spring day that had followed a cold
spell. The Colorado State Patrolman who
rescued MEH told him to sit a while. His
car would start when it had cooled down.
He had a vapor-lock. The fuel in his
carburetor had completely vaporized
because of the low pressure at that
altitude AND because of the warm day AND
because they were still selling
low-boiling, winter-formulated, volatile
fuel in Steamboat Springs, Colorado where
MEH had last filled his tank. |
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