United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
EMB Report 79-CKO-19
April 1979
Air
Benzene
Coke Ovens
Analysis of Coke Oven
By-Product Process
Samples
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ANALYSIS OF COKE OVEN
BY-PRODUCT PROCESS SAMPLES
NOVEMBER 1979
Prepared for:
Emission Measurements Branch
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
By:
TRW
ENVIRONMENTAL ENGINEERING DIVISION
P. 0. Box 13000
Research Triangle Park, North Carolina 27709
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TABLES
NUMBER PAGE
1 Benzene and BaP Analytical Results 2
2 Partial Pressure Results 6
3 GC/MS Results 11
n
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CONTENTS
Tables ii
Introduction 1
Benzene Analysis Procedure 1
Benzo-a-Pyrene Analysis Procedure 13
Appendix 16
m
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INTRODUCTION
Analyses of samples collected at several coke by-products plants were
performed in order to provide data for coke oven by-product plants. Results
of these analyses are found in Tables 1 and 2. As can be seen, the procedure
for benzene analysis included three phases: an evaluation of the liquid
sample and two gas samples. The first gas phase test is composed of the
vapor above the sample at the temperature the sample was stored. The second
gas phase test is composed of the vapor above the sample with the storage
temperature elevated by 20°C.
BENZENE ANALYSIS PROCEDURE
The analytical procedure arose from incorporating comparison analysis
with samples run on the GC/MS and quality assurance measures. The instru-
mentation used initially was found to be extremely effective and accurate.
This was two Shimadzu flame ionization gas chromatographs in conjunction
with a Shimadzu chromatopak. The chromatopak was programmed to calculate
peak area and retention times which greatly increase the accuracy of measure-
ment and identification.
Initially, the liquid samples were analyzed using 5% OV-101 + 1.75% Ben-
tone 34 columns. The results obtained with these columns proved unsatis-
factory in relation to the estimates of expected concentrations. The primary
cause of the unsatisfactory results was high concentrations of.substances
with retention times near that of benzene which caused the benzene peak to be
obscured. ,
Since the GC/MS values corresponded well with the expected concentrations,
another set of samples were analyzed using the same chromatographic conditions
I
\
1
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TABLE 1. BENZENE AND BoP ANALYTICAL RESULTS
SAMPLE
NUMBER
S77-001-601
S77-001-603
S77-001-604
S77-001-605
S77-001-606
S77-001-607
S77-001-608
1X3 S77-001-609
S77-001-610
S77-001-611
S77-001-612
S77-001-613
S77-001-614
S77-001-615
S77-001-616
S77-001-618
S77-001-620
S77-001-621
S77-001-622
. S77-001-623
S77-001-633
S77-001-634
TYPE OF SAMPLE
Treated Wastewater
Untreated Wastewater -
20% skim, 80% water sample
Water
Napthalene . .
Napthalene
Water
Untreated Wastewater -
Skimmed Oil Sheet
Wastewater
Coal Tar
Weak Ammonia Water
WaterOrganic Layer
Debenzolyzed Wash Oil
Light Oil High Crack
Light Oil -- Medium Crack
Separated Water
Tar and Condensate
Tar
Weak Ammonia Water
Weak Ammonia" Water
Tar Weak Ammonia Water
Spent Carbon Slurry
Effluent From Flotation Unit
BaP
0.0018
0.0233
0.004
. 1.380
1.130 .
0.0048
15.500
0.0015
18.000
0.100
0.0063
43.500
0.170
3.700
0.003
0.120
23.000
0.115
0,170
0.170-
0.0001
0.0092
BENZENE
LIQUID
CONC.
(ppmv)
10
2
4
350
<1
1,224
'
-------
SAMPLE
NUMBER
S77-001-635
S77-001-636
S77-001-637
S77-001-638
.577-001-639
S77-001-640
577-001-641
S77-001-642
1 S77-001-643
S77-001-644
S77-001-645
577-001-646
577-001-647
577-001-649
577-001-651
577-001-653
S77-001-655
577-001-657
577-001-659
577-001-661
577-001-663
TYPE OF SAMPLE
Carbon Adsorber Effluent
Intercepting Sump Water --.Stream B
Intercepting Sump Oil . Stream B
Enriched Final Cooler Oil
Absorber Liquor Circulatory Tank
Tar Storage
Tar Storage Sump
Benzol Scrubber Sump
Ammonia Absorber Effluent
Influent to Wastewater Treatment
Flushing Liquor Decanter - Tar
Tar Storage .
Cold Well Water
Hot Well Water
'Tar Intercepting Sump
Oil Intercepting Sump
Tar From Final Cooler
Contaminated Sump Inlet
Contaminated Water From Decanter
Oil Layer From Decanter
. Feed to Crude Stills
BaP
<0.0001
28.000
5.000
18.000
0.400
25.500
0.0322
41.500
0.0013
0.011
18.000
12.900
0.0223
O.Q352'
8.500
11.500
0.300
3.500
0.090 . .
. 7.000 .
1,320
BENZENE
LIQUID
"CONC.
(ppmv)
841
480
590
18,320
4
1.951
7
4,2561
2
2
11
6.321'
. 54
157
6
4,532
.101
560,145
29,420
120,251 .
44,383
VAPOR
CONC. TEMP.
(ppmv) (°C)
282
2,007
1,847
3,536
1,281
421
897
8,397
2,552
617
2,821**
1,229
14,427
974
221 '
5,096
18,900
75,069
15,927
5,113
9,851
45
60
60
40
48
66
70
54
33
74
96
62
28
44
49
. 28
28
32
31
17
26
VAPOR
CONC. TEMP.
(ppmv) (°C)
687
4,998**
3,721**
10,590
6,201
1,827**
3,876**
21,682
7,837
3,681**
*
4,780**
38,791
3,606
.601
6,793
57,251
' 168,553
. 63,108
. 34,547
64,439
65
80
80
60
68
86
90
74
53
94
116
82
48
64
69
48
.48 .
52
.51
37
46
*NOT ANALYZABLE BY METHOD DUE TO TEMPERATURE
**VALUES QUESTIONABLE DUE TO BOILING POINT OF BENZENE
Values checked by GC/MS
-------
SAMPLE
NUMBER
577-001-665
S77-001-667
577-001-669
577-001-671
S77-001-673
577-001-675
S77-001-677
S77-001-679
*> 577-001-681
577-001-683
577-001-685
577-001-687
577-001-689
577-001-691
S77-001-693
S77-001-695
S77-001-697
S77-001-699
S77-001-801
S77-001-802
S77-001-803
TYPE OF SAMPLE .
Drainage From Decanter for #23 Still
Drainage From Decanter for #23 Still
#20 Still Decanter Effluent
Methyl Naphthalene in Circulating Tank
#2 Carbolic Oil
#1 Carbolic Oil .
Middle Creosote
Light Creosote
Heavy Creosote
Pitch
Oil /Water Mixture From V113 Tank (oil)
. Oi 1 /Water Mixture From V113 Tank (water)
Methyl Naphthalene From #1 C.O.
Slop Tank Sump
Light Tar Storage Tank #2 .
Heavy Tar Storage Tank. #3
Inlet to Deperator
Final Cooler Sump
Rich MEA Solution
Feed to Denver Units
Debenzolyzed Wash Oil Decanter Oil
BaP
(yg/ml )
0.001
<0.0001
0.080
10.000
W W I I 1^ I I IV V IS V i** IT* MI ti w » i i
**VALUES QUESTIONABLE DUE TO BOILING POINT OF BENZENE
'Values checked.by GC/MS
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RFM7FMP
SAMPLE
NUMBER
577-003-804
S77-003-805
S77-003-806
S77-003-807
TYPE OF SAMPLE
Gale Sump Water Layer
Gale Sump Oil Layer
Underflow From Denver Unit
Overflow Pit/Sump
BaP
(pg/ml }
.140
0.001
.0015
.110
LIQUID
CONC.
(ppmv)
221
1,294
26,5
104,900
VAPOR
CONC.
(ppmv)
1,920
2,140
505
12,380
TEMP.
(°c)
48
26
28
55
VAPOR
CONC. ,!.
(ppmv) ;
4,880
2,998
1,280
47,150
TEMP.
(°c)'
68
46
48
75
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TABLE 2. PARTIAL PRESSURE RESULTS
SAMPLE
. 577-001-601
S77-001-603
S77-001-604
.577-001-605
^'577-001-606
577-001-607
577-001-608
S77-001-609
577-001-610
577-001-611
577-001-612
577-001-613
577-001-614
S77-001-615
577-001-616 '
577-001-618 .
. $77-001-620
577-001-621
PARTIAL
PRESSURE
(mmHg )
0.0091
0.0053
0.148
0.365
0.130*
0.098
0.00574
> 0.0845
1.82
1.59*
. - 0.89*
0,129
2,20
4,55
1.53
"'OJ60
!5;
STORAGE
TEMP. '
21
21
38
20
93
18-
29
29
76
82 '.
26 .
51
. : 25 .
82
58
. -54
45;
BAROMETRIC
PRESSURE
(mmHg )
758
755 .
765
750
762
750'
770
761
750 .
. 755 '
755 . ' '" .
' . 761 .
762 . ".-
771 - '
758
770 '
' ' 764 '
772
PARTIAL
PRESSURE
' (mmHg)
o.on
0.0067
0.2066
1.63
- **
0.162 .
0.0274 .
0.224
3.63*
.- **
1.560
0,0337
. . 4.34
5,41*
' -'"2t37 .'
. . '0,831
..' ij1^
STORAGE
' - TEMP. + 20°C
41
41.
58 .
40
- .113
38 '
49
49.
96. .
' 102
46
71
45
102
78
74 .
..: ,.:,^;- '
BAROMETRIC
. PRESSURE
762
748
738
. 753
_
754
762
758
755
--
739
748
749
751
762 .
752
LVALUES QUESTIONABLE DUE TO BOILING POINT-OF BENZENE,
**NOT.ANALYZABLE BY METHOD DUE TO'TEMPERATURE..
-------
TABLE 2. PARTIAL PRESSURE RESULTS (cont'd)-
SAMPLE
S77-001-622
S77-001-623
S77-001-633
$77-001-634
S77-001-635
S77-001-636
S77-001-637
S77-001-638
S77-001-639 .
S77-001-640
$77-001-641
S77-001-642
S77-001-643
S77-001-.644
S77-001-645
S77-001-646
$77-001-647
S77-001-649
PARTIAL
PRESSURE
(mmHg)
--**
0.291
0.113
0.553
0.217
1.523
1.40
2.68
9.971
0.320
0.685 '
:6.38
1.95.
0.470
2.13*
0,930
11,11
0.739
STORAGE
TEMP.
(°c)
100
51
40
46
45
60
60
40 '
48 .
66
70
54
33
'74
96
62
28 .
44
BAROMETRIC
PRESSURE
(mmHg)
-- ** '
765
769
768
770
759 -
760
759
758
760 ..
764
760 .
764
762
755
757 .
770 ' .. . '
759 '
PARTIAL
PRESSURE-
(mmHg)
**
: 0.428
0.396
2.02
0.521
3.82*
2.89*
8.09
4.58
. 1.40*
. 2.94*
16.52
5.87
2.79*
.. **
3.59* :
28.9 ;,-:
. 2.77
STORAGE
TEMP + 200C
(°C)
120
71
60
66
65
80
80
.60
68
86
90
74 .
53
94
116
82
48
64
BAROMETRIC
PRESSURE
(mmHg)
740
747
770
758
765
777
764
739
765
759
762
749
.759
' 751
745
768
*VALUES .QUESTIONABLE DUE TO BOILING POINT OF BENZENE-
**NOT ANALYZABLE BY METHOD.DUE TO TEMPERATURE, .
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TABLE 2. PARTIAL PRESSURE RESULTS (cont'd)
SAMPLE
577-001-651
S77-001-653
S77-001-655
S77-001-657
oo 'S77-001-659
S77-001-661
S77-001-663
S77-001-665
S77-001-667
S77-001-669
S77-001-671
.S77-001-673
S77-001-675
S77-001-677 .
577-001-679
S77-001-681
S77-001-683
. 577-001-685
PARTIAL
PRESSURE
(mmHg)
0.168
3.87
14.57-
57.20
12.30
3.83
7.60
17.38
17.67
2.09.
10.07
11,41, .
13,52 :.'
3.20*
. 0.130
0.756* .
' 0.168* .
39,91'
STORAGE
TEMP.
4.9
28
28
32
31
17
26
21
21
24
65
7.9
42"
150
62
104
23,9
60
BAROMETRIC
PRESSURE
(mmHg)
760
760
771
762
772 .
750
771
768
766
770 . .
758
770
756
765
760 ..
771 , ' '
759 '. . ..'
762 ' .
PARTIAL
PRESSURE
(mmHg)
0.450
5.15
43.8
128.1
46.7
26.05
48.84
20.29'
33.15
10.0 .
35.39*
. . 29.11*
33,8
. **
0.562
.' ' 2,13
** . _
' " 149,0*
STORAGE
TEMP + 2QOC
69
,48
48
52
.51
37
. 46
41
41
.44
85
99 .
. , 62
170
82
.124 .
' ' 259 ' .
. ' 80
BAROMETRIC
PRESSURE
(mmHg )
747
758
765
760
740
754 .
758
762
764
762 .
750
.741
748
*
768
' 762
' 750' ; '
*VALUES QUESTIONABLE DUE TO BOILING POINT OF BENZENE,
**NOT ANALYZABLE BY METHOD DUE TO TEMPERATURE,
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TABLE 2. PARTIAL PRESSURE RESULTS (concluded)
SAMPLE
S77-001-687
S77-001-689
577-001-691
S77-001-693
S77-001-695
S77-001-697
S77-001-699
S77-003-801
S77-003-.802
S77-003-803
S77-003-804
S77-003-805
S77-003-806
S77-003-807
PARTIAL
PRESSURE
(mmHg)
1.55
2.40. .
. 0.561
0.301
4.60
6.47 '
4.79
0.0924
0.678
0.965
1,45 .
1.63 '
0.389
9.5Q- .
STORAGE
tEMP.
60
60
" 37
60
71
69
52
32
29 '
28
48
26
28-
55
BAROMETRIC
PRESSURE
(mmHg )
771
774
770
759
774
768
762
764
758
755
754
761
770
767
PARTIAL
PRESSURE
(mmHg)
3.19*
6.77*.
1.81
1.24* .
10.92*.
22.27*
14.41
0.307
1.56
3.01
3.72 :
2.25
0.978
35.41
STORAGE
TEMP + 20°C
(OC)
80
80 .
57
80
91
89 ,
72
52
49
48
68 .
46
48
75
BAROMETRIC
PRESSURE
(mmHg)
758
757
752
762
768
758
760
780
111
772
762
750
764
751
*VALUES QUESTIONABLE DUE TO BOILING POINT OF BENZENE,
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as-the GC/MS. (The GC/MS results are presented in Table 3.) This procedure
called for 0.2%. Carobwax 1500 on Carbopak-C columns with a temperature
program of 50°C to 140°C at a rate of 16°C per minute. The procedure
followed was identical, with the exception of a 15°C per minute rate for the
temperature program set by the 5°C per minute rate increments on the Shimadzu
gas chromatographs. The 0.2% Carbowax 1500 on Carbopak-C columns were much
more desirable for this analysis since they efficiently separated benzene 7
from the other substances, regardless of their concentration, by increasing
the retention times of each substance. The second set of samples produced
the same values obtained with the GC/MS, so this procedure was adopted for
the rest of the analysis.
Tv/o problems became apparent with respect to reproducibility and quality
in the analysis of the liquid samples. First, a procedure for blanking the
gas chromatograph and injection syringes was .needed. It was found that the
instrument required time and flushing with both carbon disulfide and nitrogen
to remove high concentrations of substances, including benzene, found in many
of the liquid samples. The syringes were also contaminated by each liquid
injection and flushing with carbon disulfide with the aid of a high vacuum
pump and syringe cleaner was necessary. For quality assurance purposes,
blanks on both the instrument and syringe were required before each sample
injection. This repeatability requirement for each sample increased greatly
the time required for analysis.
The second problem encountered with the liquid samples arose in the prepa-
ration of accurate standards. Initially, standard pipetting methods and serial
'»
dilutions were used but proved inaccurate.' To remedy this situation, a 5 ml
syringe and serial dilutions were used to prepare the standards. After many
repeatable runs, these standards were plotted graphically and mathematically
I
10
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TABLE 3
GC/MS RESULTS
SAMPLE #
577-001-640
577-001-642
577-001-646
577-001-693
ppmv
by
GC/MS
4.0
>2000*
7.0
8.0
ppmv
by
GC
1.95
4,256
6.32
9.12
* Detector flooded
11
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and were found to be linear, thus assuring the quality of the standards.
The gas phases of the analysis also had similar problems. For both the
ambient collection temperature tests and the 20°C elevation temperature tests
the Shimadzu Gas Chromatographs with the 0.2% Carbowax 1500 on Carbopak-C
columns and 50°C to 140°C temperature program were used. Again with the gas
phases, there were problems associated with blanking the machines and syringes.
To remove the contamination in the columns, a flushing with pure nitrogen gas
was used. A switch from glass syringes to disposable syringes removed the
necessity for blanking the syringe between each sample.
The standards used for the gas analysis were commercially prepared by
Scott Specialty Gases. Several different concentrations were analyzed,
plotted graphically and found to be linear, thus assuring quality of the stan-
dards.
A third quality assurance measure was taken in the gas phases analysis.
The Shimadzu gas chromatographs have a separate external loop for gas sampl-
ing which aids in sample size repeatability. The trap size is 1 ml but a
10 ml sample is injected through the loop to assure a complete sample. The
sample in this analysis is specific for temperature so the sample loop was
controlled at the gas collection temperature. This assures that the sample
is monitored at the required temperature.
One additional procedure was instituted to insure validity of the results
for the gas phase analysis. The initial analysis was carried out by storing
the liquid in a container controlled at the liquid storage temperature. For
the lower temperature samples (up to 40°C), a glass vial with teflon lid and
septum was used to store the sample while 'bringing it up to the storage
perature. For higher storage temperature samples, a standard Parr bomb
apparatus v/as used to eliminate the possibility of container rupture due to
12
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internal pressure. This device is a completely sealed steel container with
an inner container of all teflon. In both cases the containers were carefully
opened under a hood to release pressure, then a gas phase sample was quickly
extracted through either the septum or a small opening around the lid using
a gas-tight syringe. The sample was then raised slowly by 20°C and the
procedure repeated. Some samples showed lower values at the + 20°C tempera-
ture, indicating benzene depletion in the sample. To correct this- problem,
a fresh aliquot was used for the temperature + 20°C analysis. Temperatures
were maintained by immersing the sample in a constant temperature water bath,
and in all cases the liquid level in the containers was approximately 75
percent of the volume of the container. The containers were 80 mi Hi liters in
volume.
The procedure described above with the modifications for both liquid
and gas samples was adopted and all the samples were re-analyzed using these
methods and quality assurance techniques.
Several of the samples collected for benzene were to be analyzed for
the vapor phase at temperatures above the normal boiling temperature for
benzene. This v/ould produce a boiling condition, which would not give a
representative, steady state value. Therefore, these values are questionable.
A few samples could not be analyzed effectively due to the frothing or rapid
boiling at the designated temperature.
BENZO-a-PYRENE ANALYSIS PROCEDURE . '
Fluorescence spectrophotometry was used to analyze for BaP. The
equipment used for this analysis was the Aminco Model SPF-125 Spectrophoto-
fluorometer with 7mm lightpath cell. This instrument accurately measures
concentrations of BaP as low as 0.001 ppm. The wavelength settings were
378 nm excitation and 403 nm emission with respective slitwidth openings of
13
-------
Imn and 5mm. All the samples were in a liquid state, so the only preparations
involved examining each sample and diluting in cyclohexane any sample which
was darkly colored, contained abundant suspended material, or was extremely
viscous. This was necessary because any particles or opacity will affect
the absorbence. This instrument becomes extremely substance specific at very
narrow slit widths, as were used in this analysis.
Filtered particulates and solid samples required an eight hour extrac-
tion period in cyclohexane before analysis could be performed. A cyclohexane
blank was run and taken into account on all extracted and diluted samples in
the final calculations.
The quality assurance procedures taken for this analysis included pre-
paration of a series of BaP standards, exclusion from light, and spiking. A
set of standards were prepared for each range (high, medium, and low concen-
trations) by serial dilutions. Each set was'"analyzed for linearity by
continual measurement throughout the days testing. Since BaP is light sensi-
tive, standards and sample aliquots were discarded after analysis and the
samples were kept in closed, dark containers. Lastly, a spiking procedure
was used to determine recovery efficiencies on solid and filtered samples,
and on samples with very low BaP concentrations. A spiking procedure was
followed to assure accurate detection near the limits of the machine.
No major problems were encountered with the fluorescence spectrophoto-
metric procedure for BaP analysis. This method is preferred over the thin
layer chromatographic (TLC) method for low level BaP analysis, as the TLC
method had only about 0.01 the sensitivity of direct liquid measurement..
r,
On higher concentration samples, selected samples were re-run using TLC
and a TLC scanning attachment for the fluorescence spectrophotometer.
14
-------
Comparable results were produced.
The benzo-a-pyrene method was tailored to these samples. The method
originally chosen was intended to be a thin layer chromatography separation
with measurement by scanning in-situ with a scanning attachment for the
fluorescence spectrophotometer.
This method lacked the sensitivity required for the analyses. The
samples were to be pre-concentrated using Kuderna-Danish concentrators with
a nitrogen stream flowing over them. However, most of the samples would not
reduce in a reasonable time. Some samples took several weeks to reduce their
volume by 50 percent while others would not reduce within two weeks, even
with ethanol added. It was found by reviewing the literature that no compound
expected to be present in these samples had a similar excitation/emission
spectrum to benzo-a-pyrene. Previous analyses by GC/MS on similar samples .
were the basis of the compounds to be considered as interferences. In. addi-
tion, a general compendium of poly-organic materials and other organtcs showed
no similar spectrum. It was, therefore, decided to go to a direct in-situ
method as previously described.
Fluorescence and Phosphorescence Data Compendium,
Donald L. Helman, American Instrument Co., 1977.
15
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APPENDIX
Calculations
Benzene
Partial Pressure
Benzo-a-Pyrene
Typical Chormatograms - Benzene Standards
Typical BaP Calibration Chart
Typical BaP Calibration Curve
16
-------
CALCULATIONS
Benzene
1. Prepare standard curve to check linearity.
2. Calculate constant (K) by: area (from chromatopak)
' J concentration of standard
3. Concentration of benzene in sample: (area) x (K)
Partial Pressure
Assuming an ideal gas: ^oles benzene (pressure)
10 moles total
Therefore: PPmv benzene (Atmospheric Pressure mm Hg)
10 ppmv total
Benzo-ct-Pyrene
1. Prepare a standard curve.
2. Read, "as analyzed" concentration from curve.
3. Correct by dilution factor, if any.
17
-------
TYPICAL CHROMATOGRAM
BENZENE STANDARD
,'.. .-'--.i PPM
fIVEL 21.2
THPT OR. .16. 15.28.
9.4
'ti
r! i H
18=74
C-RtH
?:MPL *
FILE *
REPT ft
METHOD
ji
0
iji
fl£l
2
6
41
HHHE TIME
9.4
10.74
'i'OTflL
p
'^'
rfiNC f'1K
4.4572
93.5427
99.9999
RRER
319
6838
7158
i EVEL
-15
2J..4
18
Vi. -
-------
TYPICAL CHROMATOGRAM
BENZENE STANDARD
STflRT Q8.16.15.52.
fi.4
LEVEL -281.2
L£V EL
-18
16.34
STOP
ORlfl
SMPL tt m
FFLE * 2
METHOD 41
» HHf'iE TIME
e
CONC MK
0.3335
i-3.^-4
RRtH
377
c a «\ <
19;
-------
TYPICAL CHROMATOGRAM
BENZENE STANDARD
PPM
" 98,16.16.33.
18.41
STOP
f:-P!R
00
FILE *
PEPT #
METHOD
if
i?
2
3
41
MRMF
TIME
e.33
COHC
0.071
9
flREfl
376
, - -_ . c <
20
-------
F"
5
/L
O
1
A_JL
,_..
-
P xx
\ -
~i
_L_I^_
f
V3
~n~rr^z:~!'~'
TT
1-1-
-pJ_r^
i, -i'j:,-
BaP STANDARDS - pg/ml
21
-------
Calibration Curve for BAP Analysis
0-
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