Title: Topics for Today
1Sam dedication lecture!
2(No Transcript)
3Topics for Today
- Whats all the other stuff in my gasoline?
- Quiz 8
4Topics for Today
- Gasoline additives (MTBE, ethanol, and oxygenates)
5Readings for Today
- 4.10 Newer fuels and other sources
6Topics for Monday (April 10!)
- The other part of crude oil
7Topics for Monday (April 10!)
8Readings for Monday
- 9.1 Polymers The long, long chain
- 9.2 The Big Six
- 9.3 Addition polymerization
- 9.4 Polyethylene
9Topics for Today
- Whats all the other stuff in my gasoline?
- Quiz 8
10Review
What is the problem with using winter blends in
the summer?
Is the gasoline in the winter more or less
volatile than in the summer?
MORE!
11What is wrong with VOCs?
Becomes more volatile ? VOCs!!
12Should you use the summer blend in the winter?
Why not?
13Does this have anything to do with the octane
number?
NO!!
14What is the octane number?
15- Octane number A measure of how effective a fuel
can resist engine knock.
In other words, how smooth is the combustion of
the fuel?
What is engine knock?
16High octane number smooth burning fuel. More
of a controlled burn.
Low octane number Uncontrolled explosion
How do we determine octane number?
17octane rating 100
Define!
- Iso-octane
-
- CH3 CH3
-
- CH3 C CH2 CH CH3
-
- CH3
18octane rating 0
Define!
n-heptane
H
H
H
H
H
H
H
C
C
C
C
C
C
C
H
H
H
H
H
H
H
H
H
19In the old days
Mix various amounts of n-heptane and isooctane to
see when a test-engine will knock.
20- n-heptane 0
- Isooctane 100
21Another example
22Octane -20!
- n-octane
-
- CH3CH2CH2CH2CH2CH2CH2CH3
-
23octane rating 100
- Iso-octane
-
- CH3 CH3
-
- CH3 C CH2 CH CH3
-
- CH3
24Branched molecules tend to have higher octane
numbers!
Why do we care?
25The gasoline from crude oil has an octane number
of about 60-70.
26BUT
Recommended for most cars
27Why do we use fuel additives?
1) To increase the octane number
28Octane rating 123!
Very toxic. Not used too much anymore
29Octane rating 114!
CH3
30Octane rating 108!
31Alcohol R O H
R some hydrocarbon group (methyl, ethyl, etc)
32Very smooth burn!
Ethanol Ring of Fire!
33Tetraethyl lead
Octane rating 270!
CH2CH3 CH2CH3
Pb CH2CH3
CH2CH3
34Also called ethyl in the old days
35TEL
Why not?
TEL is not used anymore
36Criteria Pollutants
Lead is an extremely potent neurotoxin
- Defined by the EPA
- CO
- SO2
- NOx
- PM2.5 and PM10
- O3 (ozone)
- lead
TEL was banned in the US in 1976
Lead is not very interesting anymore
37If you put 89 octane into your 87 octane car
NOPE!
More power?
38Why do we use fuel additives?
1) To increase the octane number
2) To make a cleaner fuel
39Oxygenates!
Take a hydrocarbon
And just add oxygen!
40Why add oxygen to the fuel?
Review
41If we add oxygen to the fuel, then we can reduce
CO and PM emissions!
Complete Combustion
C O2 ? CO2 C ½ O2 ? CO C O2 ? C O2
Not enough oxygen
Severely depleted oxygen
42Oxygenates
An alcohol
43Spark Plug
Ethanol cannon!!
44Why must ethanol be added at the pump?
Polar or nonpolar?
Is gasoline polar or nonpolar?
45(No Transcript)
46Whats good about using ethanol?
1) Reduced CO emissions
472) Less direct impact if spilled
Whats good about using ethanol?
1) Reduced CO emissions
48Problems with ethanol?
49(No Transcript)
50September 2005 Report
What if WI mandated the use of 10 ethanol across
the state??
51Air Pollution Implications
- means decreased emission means increased
emission
52Problems with ethanol?
1) Air pollution compromise