Gasoline and Diesel Fuel Quality
Confirmation and Composition by FTIR
Gulf Coast Conference 2012
Agilent Mobile Spectroscopy 5500/4500 FTIR
Frank Higgins Applications Development Scientist October 2012
October 12, 2012 1
Product Portfolio – In Lab Systems
Physical Attributes • 8 lbs • 8” x 8” x 4.5” • External Computer • USB connection • External Power • Full spectral analysis
4500 Series FTIR
Physical Attributes • 15 lbs • 8” x 11.5” x 7.5” • Integrated PDA computer • Optional PC • Internal battery • Dedicated sample interface
• Designed for field use
5500/4500 Series FTIR Sampling Interfaces
Single Transmission Cell
• Fixed path length liquid transmission cell – Standard 100µm
• Liquids only • Quantitative analysis
– 50 ppm to 5 % • Reproducible and easy to use
October 12, 2012 4
5500t FTIR
Single Transmission Cell Operation
October 12, 2012 5
1. Place Sample on Lower Window
3. Once in place analyze
the sample
2. Rotate into place
4. Cleaning is easy!
Gasoline in Diesel Fuel
Gasoline fuel contamination in diesel fuel causes engine failures Causes coke formation on fuel injectors, and excessive wear on fuel
contact parts Problem is worse in Ultra low sulfur diesel (ULSD) engines Much less lubricity than off-road, agricultural or older diesel
formulations Sulfonated hydrocarbons are removed in ULSD
Gasoline can wash varnish deposits into the engine
Lowers the diesel cetane value or energy content
Manufacturers want proof of no gasoline in diesel for warranty engine repairs
October 12, 2012 Confidentiality Label
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Gasoline, 87 Oct Diesel
Gasoline in Diesel Fuel
Wavenumber 3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
Abso
rban
ce
Ethanol Light
Aromatics
Aromatic IR bands from gasoline are best to quantitate the amount of contamination
Ethanol bands are strong with less interference with diesel but are less suitable for quantitative analysis. Pipeline gasoline contamination might not have ethanol Amount used in gasoline varies Some gasolines can use MTBE or ETBE as oxygenates with little or
no EtOH
October 12, 2012 Confidentiality Label
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Gasoline in Diesel Fuel
1606
1505
14
93
1378
1307
876
848
833
806
780 76
6 75
1 741
723
699
Diesel, Danbury CT
1750 1700 1650 1600 1550 1500 1450 1400 1350 1300 1250 1200 1150 1100 1050 1000 950 900 850 800 750 700
3.0
2.5
2.0
1.5
1.0
0.5
0.0
Wavenumber
Abs
orba
nce
729
1607
1516
14
96
1379
1340
1273
1171
1091
1051
967
881
806
795
768 74
2
695
676
Petrol_Gasoline, Danbury CT
1750 1700 1650 1600 1550 1500 1450 1400 1350 1300 1250 1200 1150 1100 1050 1000 950 900 850 800 750 700
3.0
2.5
2.0
1.5
1.0
0.5
0.0
Wavenumber
Abs
orba
nce
Mono phenyl (5 adj. H wag); & 4 adj. H wag
CH2 Rock, Long chain
Mono/meta phenyl, ring pucker
Meta phenyl, 3 adj H wag
Para 2 adj. H wag Lone H wag, Meta phenyl &mono naphthyl
Toluene
Ben
zene
/met
a xy
lene
Meta Xylene Para Xylene
Ortho Xylene
Ethanol
Total Aromatic, Aromatic Ring Quadrant stretch
Aromatic Ring semicircle stretch
Total Aromatic, Aromatic Ring Quadrant stretch
Aromatic Ring semicircle stretch
Gasoline in Diesel Fuel
1150 1100 1050 1000 950 900 850 800 750 700
0.60
0.55
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
-0.05
Wavenumber
Abs
orba
nce
Ethanol, Gasoline
Diesel Aromatics
Toluene, Gasoline
Benzene, Gasoline
0.0% Gasoline 0.5% Gasoline 1.5% Gasoline 3.0% Gasoline 5.0% Gasoline
Gasoline in Diesel Fuel
4331
.5
4258
.9
4167
.5
4069
.1
3633
.3
3602
.2
3347
.7
4600 4500 4400 4300 4200 4100 4000 3900 3800 3700 3600 3500 3400 3300 3200 3100
0.20
0.18
0.16
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0.00
Wavenumber
Abs
orba
nce Ethanol, Gasoline
Diesel Hydrocarbons 0.0% Gasoline 0.5% Gasoline 1.5% Gasoline 3.0% Gasoline 5.0% Gasoline
Gasoline in Diesel Fuel
Winter diesel has more aromatics relative to summer diesel. This causes some interference with the measurement of the
gasoline aromatics. Chemometrics or partial least squares (PLS) calibration models help
reduce the interference from these seasonal variations. PLS models are “trained” with gasoline in diesel standards
prepared from both winter, summer, and 50/50 mixed diesel. PLS calibrations allow the use of multiple regions of the spectra. Agilent’s Microlab software includes conditional reporting
Determines which calibration model is best for the current sample spectrum
Chooses winter, summer, or mixed diesel calibrations. These capabilities allow for more robust and reproducible gasoline
in diesel measurements by FTIR.
Gasoline in Diesel Fuel
804.626 0.210
pct gasoline(691.497 -0.003)
pure winter diesel test1_2011-08-12t11-15-49(1)
2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700
0.70
0.65
0.60
0.55
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
-0.05
-0.10
Wavenumber
Abs
orba
nce
IR spectra of pure summer diesel (blue) and pure winter diesel (purple). The light aromatics from gasoline absorb in this region as well, but have
frequencies that are shifted relative to the diesel aromatics.
Gasoline in Diesel Fuel
October 12, 2012 Confidentiality Label
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Gasoline in Diesel Fuel Final gasoline in diesel PLS calibration model (vol% Gasoline): SECV= 0.100, R2= 0.9957, 6 factors, LOQ=0.225
5
2
4
3
1
0
Actual Gasoline Concentration (vol%)
Pre
dict
ed G
asol
ine
Con
cent
ratio
n (v
ol%
)
5 2 4 3 1 0
805.
8 2
.507
Petro
l tol
uene
(728
.7 0
.001
)
Pt
l b(6
762
001
2)
1638
.0
1277
.7
diesel fuel audi vin wa1am7419d035555_2010-05-28t11-49-15(1)
1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
-0.1
Abs
orba
nce
Alkyl Nitrate, Cetane booster
Aromatics
Cetane Booster in Diesel Fuel
Biodiesel Analysis
Increased use of Biodiesel. Many countries allow or require biodiesel in regular diesel Some states allow up to 3% biodiesel in diesel without disclosure
Biodiesel is not appropriate for all fuel uses Can clog filters, reduce cold weather performance, or cause problems with
storage. Need exists to measure biodiesel for 2 different goals
1. Monitor % biodiesel for blending B5, B10, B50 Regulatory and compliance
2. Monitor low levels of biodiesel as a contaminant 0.025% to 20%
Regulatory methods specify FTIR EN 14078 : 2009 Transmission Liquid Cell ASTM D7371-07 Mulitple Reflection ATR
Agilent 5500a Multibounce FTIR ASTM D7371-07 Biodiesel in Diesel (1-100%)
October 12, 2012 Confidentiality Label
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Multi-reflection Sampling Crystal – 5500a ASTM D7371-07 Biodiesel in Diesel (1-100%)
October 12, 2012 Confidentiality Label
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Agilent 5500 DialPath
EN 14078 : 2009 Biodiesel in Diesel (0.5-25%)
October 12, 2012 Confidentiality Label
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DialPath Accessory –Closed EN 14078 – 2009 (0.5-25%)
October 12, 2012 Confidentiality Label
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1
2
3
4
5
15
16
17
18
19
29 30 33 34
Quant Validation Plot for EN 14078:2009 Range A Biodiesel % (V/V) R²=1.000
0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40
2.5
2.0
1.5
1.0
0.5
0.0
Peak Height Absorbance
Bio
dies
el C
once
ntra
tion
%(v
/v) % Biodiesel = 5.567(x) – 0.069
Biodiesel Analysis- Range A Biodiesel in Diesel Calibration Plot
Bio
dies
el %
(V/V
)(17
47.2
) Biodiesel in Diesel EN 14078:2009 Range A
1820 1810 1800 1790 1780 1770 1760 1750 1740 1730 1720 1710 1700 1690 1680 1670 1660
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
-0.05
-0.10 Wavenumber
Abso
rban
ce
0.50
Biodiesel Analysis- Range A Biodiesel in Diesel Spectral Overlay
1
3
4
5
6
7
15
17
18
19
20
21 Quant Validation Plot for En 14078:2009 Range B Biodiesel % (V/V) R²=1.000
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3
7
6
5
4
3
2
1
0
Peak Height
Con
cent
ratio
n
% Biodiesel = 5.595(x) - 0.074
Biodiesel Analysis- Range B Biodiesel in Diesel Calibration Plot
Bio
dies
el %
(V/V
)(17
47.1
)
Biodiesel in Diesel EN 14078:2009 Range B
1820 1810 1800 1790 1780 1770 1760 1750 1740 1730 1720 1710 1700 1690 1680 1670 1660
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
-0.2
Wavenumber
Abso
rban
ce
Biodiesel Analysis- Range B Biodiesel in Diesel Calibration Plot
Biodiesel Methods
Method Name Components Fuel - Biodiesel % in Diesel Version4.a2m Biodiesel 0.025% – 1% *requires 5500t/4500t or DialPath Biodiesel 1% - 10% Biodiesel 10% - 20% Interference – water vapor Interference – diesel oxidation Fuel - Biodiesel ASTM D7371-07 Version3.a2m Biodiesel 1% - 10% *requires 5500/4500a w/ Multi-reflection ATR Biodiesel 10% - 30% Biodiesel 30% - 100% Fuel - Biodiesel EN 14078 2009 Version4.a2m Biodiesel 0.5% -20% *requires 5500/4500 DialPath Peak area @ 1745 cm-1 Fuel - Water in Diesel Version4.a2m Water in diesel 100 ppm – 900 ppm *requires 5500t/4500t or DialPath Water in diesel 900 ppm –3000 ppm *requires Water in Oil Surfactant Kit Diesel oxidation
Petrochemical - Fuel Methods
In addition to Biodiesel contamination, the 5500/4500 can be used to determine fuel quality parameters.
• Water Contamination – Gasoline – Diesel
• Gasoline contamination in diesel • Gasoline performance characteristics
– Oxygenates, RON, MON, Aromatics
Method Name Fuel Type Sample Interface Components Range Fuel - Gasoline Analysis PAL Gasoline TumblIR
MTBE 0.25-16.5 vol% ETBE 0.25-16.5 vol%
Ethanol 0.1-16.5 vol% Total Aromatics 0.5-45 vol%
Total Olefins 2-12 vol% Benzene 0.2-2.5 vol% Toluene 0.5-25 vol%
RON 85-97 MON 80-86 Water Relative
Fuel - Gasoline Water Analysis Gasoline TumblIR Water 150-6000ppm
Fuel - Water in Diesel Stabilized Diesel TumblIR Water 100-4000ppm
Oxidation Relative Fuel - Water in Gasoline (0-80%) Stabilized Gasoline TumblIR
Water 0 - 80 vol% Fuel - Gasoline in Diesel Version5 Diesel TumblIR
Gasoline 2000-10000ppm Oxidation Relative
Antioxidant 150-10000ppm
Petrochemical - Fuel Methods
October 12, 2012 Confidentiality Label
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Ethanol in Gasoline – High Concentrations
Typical standard US gasoline contains 7-10% ethanol (EtOH). New flexfuel engines allow the use of E85 gasoline
E85 has less exhaust emissions High volatility increases octane level and horsepower Lower combustion and exhaust temperatures Renewable Can be produced locally
E85 has some draw backs 30% less energy per gallon compared to normal gasoline with 10% EtOH
On a mileage basis it may be more expensive than normal gasoline Ethanol is hydroscopic and water build up is a potential problem if fuel sits for
a long period of time Inconsistency can cause engine tuning/performance problems
October 12, 2012 Confidentiality Label
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Ethanol in Gasoline – High Concentrations
Inconsistency Problem 85% EtOH is the maximum spec in E85 gasoline E85 can be in spec with as little as 51% EtOH Gasoline is added to meet volatility requirements Seasonal variations in temp require different formulations
Actual EtOH concentrations in E85 can vary widely from pump to pump Auto manufacturers need a fast and easy onsite EtOH in gasoline measurement
Aides in diagnosing engine problems or failures Warranty issues
Ethanol in Gasoline 0-100% The overlaid IR spectra of ethanol in gasoline calibration standards measured at 100um with the DialPath accessory.
October 12, 2012 Confidentiality Label
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ETO
H(1
924.
1)
100v pct etoh, 100um dp6 630 64scns_2012-07-03t16-28-24(1)
2700 2600 2500 2400 2300 2200 2100 2000 1900 1800 1700
.4
.2
.0
0.8
0.6
0.4
0.2
0.0
Wavenumber
High concentration ethanol in gasoline calibration Nine calibration standards are prepared volumetrically in the 0-100% ethanol range. The peak area at 1924cm-1 is used for this Beer’s Law calibration plot.
October 12, 2012 Confidentiality Label
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12
1316
1723
3233
34
35
36
37
38
39
43
Quant Validation Plot for ETOHR²=0.999
0 1 2 3 4 5
100
90
80
70
60
50
40
30
20
10
0
Peak Area
Con
cent
ratio
n
MicroLab FTIR Software: Fuel – Ethanol in Gasoline 0-100% 100um Final result using a 30 second measurement.
October 12, 2012 Confidentiality Label
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Water in oil
Low PPM Water quantification by FTIR • Turbine • Gear • Hydraulic • Bunker fuel • Crude Oil • Biodiesel • Diesel • Gasoline • Water/glycol mix
PLS Method with Surfactant: Water in Turbine Oil
Addition of surfactant “oil stabilizer” to the turbine oil • Creates a stable emulsion • Maximum IR water absorbance achieved at 3% surfactant • Two different non-ionic PEO based surfactants used Three fold increase in water absorbance • Less IR scattered light, more absorbed • Smaller water particle (micelle) sizes, with a narrower distribution Water measurements are very reproducible Variability in the non-surfactant method has been eliminated
Preliminary PLS Analysis: Water in Turbine Oil Without Surfactant
turbine oil water.tdf,105 (R² = 0.859309544)turbine oil water.tdf,105 (R² = 0.859309544)
Actual Concentration ( C1 )Actual Concentration ( C1 )
Pred
icte
d C
once
ntra
tion
( F11
C1
)Pr
edic
ted
Con
cent
ratio
n ( F
11 C
1 )
-400
200
800
1400
-100 200 500 800 1100 1400 1700
-400
200
800
1400
-100 200 500 800 1100 1400 1700
91
92
93
94
103
104105
106
107
118
119
120
121
122
133
134
135
136
145
146147
148
158
159
160
161
172
173
174
175
185186187
188
199200201202
211212213214
224
225
226
227
238239
240242
253254
255
256
265
266
267
268
277
278
279
280281
294295
296297
306
307
308
-400
200
800
1400
-100 200 500 800 1100 1400 1700
300ppm span 500ppm Span
FT-IR subtraction spectra without surfactant: 1200ppm standard minus 20ppm spectra on four Instruments – Water absorbance is weak and inconsistent
3410
.8
4600 4400 4200 4000 3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 600
0.022
0.020
0.018
0.016
0.014
0.012
0.010
0.008
0.006
0.004
0.002
0.000
-0.002
Wavenumber
Abso
rban
ce
Water OH stretch
Water HOH Deformation/ Scissors
Water hindered Rotation
1127
.5 0
.313
6
3454
.3
4200 4000 3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 600
0.045
0.040
0.035
0.030
0.025
0.020
0.015
0.010
0.005
0.000
Wavenumber
Abso
rban
ce
FT-IR subtraction spectra with surfactant: 1300ppm spectra minus 5ppm spectra on four Instruments (3x more abs.)
IR spectral overlay of turbine oil (Mobil DTE) calibration standards 5-4300ppm, with surfactant stabilizer
3950 3900 3850 3800 3750 3700 3650 3600 3550 3500 3450 3400 3350 3300 3250 3200 3150 3100 3050
0.22
0.20
0.18
0.16
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0.00
-0.02
-0.04
-0.06
-0.08
Wavenumber
Abs
orba
nce
turbine water surf actant.tdf ,25 (R² = 0.998029969)turbine water surf actant.tdf ,25 (R² = 0.998029969)
Pre
dic
ted C
onc
entr
atio
n (
F4 C
1 )
Pre
dic
ted C
onc
entr
atio
n (
F4 C
1 )
2500
4000
5500
2500
4000
5500
20
21222324
252627
28
2931
32
49505152
545556
57585960
616364
2500
4000
5500
PLS Actual vs. Predicted Quant Plot: Water in Turbine, w/ Surfactant Stabilizers (5-5500ppm)
5500t Predictions: Water in Turbine Oil w/ Surfactant
Stabilizers
PAL (ppm) KF (ppmDifference
(ppm) % Error525 504 21 4.2
1052 965 87 9.02027 2002 25 1.22914 2838 76 2.74835 4753 82 1.7
Fuel Analysis - Conclusions
The 4500t/5500t or DialPath can be used for multiple fuel analysis applications
Gasoline in Diesel
0.2-10% gasoline range
Works in summer, winter, or mixed season diesel
Biodiesel concentration in diesel fuel
Both mixing and contamination levels
Ethanol in Gasoline
Covers the high concentration range for E85 gasoline
Uses the same 100um DialPath or TumblIR used for other oil and fuel methods
Calibrations are pre-defined in the Microlab software
Water in turbine oil surfactant technology applies to diesel, gasoline, and crude oil
Makes FTIR water measurements consistent
Calibrated to Coulometric Karl Fischer water
Easy to use step by step method