ASTM D6277-99
(Test Method)Standard Test Method for Determination of Benzene in Spark-Ignition Engine Fuels Using Mid Infrared Spectroscopy
Standard Test Method for Determination of Benzene in Spark-Ignition Engine Fuels Using Mid Infrared Spectroscopy
SCOPE
1.1 This test method covers the determination of the percentage of benzene in spark-ignition engine fuels. It is applicable to concentrations from 0.1 to 5 volume %.
1.2 SI units of measurement are preferred and used throughout this standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 6277 – 99 An American National Standard
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Test Method for
Determination of Benzene in Spark-Ignition Engine Fuels
Using Mid Infrared Spectroscopy
This standard is issued under the fixed designation D 6277; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 3. Terminology
1.1 This test method covers the determination of the per- 3.1 Definitions:
centage of benzene in spark-ignition engine fuels. It is appli- 3.1.1 multivariate calibration—a process for creating a
cable to concentrations from 0.1 to 5 volume %. calibration model in which multivariate mathematics is applied
1.2 SI units of measurement are preferred and used through- to correlate the absorbances measured for a set of calibration
out this standard. samples to reference component concentrations or property
1.3 This standard does not purport to address all of the values for the set of samples.
safety concerns, if any, associated with its use. It is the 3.1.1.1 Discussion—The resultant multivariate calibration
responsibility of the user of this standard to establish appro- model is applied to the analysis of spectra of unknown samples
priate safety and health practices and determine the applica- to provide an estimate of the component concentration or
bility of regulatory limitations prior to use. property values for the unknown sample.
3.1.1.2 Discussion—Included in the multivariate calibration
2. Referenced Documents
algorithms are Partial Least Squares, Multilinear Regression,
2.1 ASTM Standards: and Classical Least Squares Peak Fitting.
D 1298 Practice for Density, Relative Density (Specific
3.1.2 oxygenate—an oxygen-containing organic compound
Gravity), or API Gravity of Crude Petroleum and Liquid which may be used as a fuel or fuel supplement, for example,
Petroleum Products by Hydrometer Method
various alcohols and ethers.
D 4052 Test Method for Density and Relative Density of
3 4. Summary of Test Method
Liquids by Digital Density Meter
D 4057 Practice for Manual Sampling of Petroleum and 4.1 A sample of spark-ignition engine fuel is introduced into
Petroleum Products a liquid sample cell. A beam of infrared light is imaged through
D 4177 Practice for Automatic Sampling of Petroleum and the sample onto a detector, and the detector response is
Petroleum Products determined. Wavelengths of the spectrum, that correlate highly
D 4307 Practice for Preparation of Liquid Blends for Use as with benzene or interferences, are selected for analysis using
Analytical Standards selective bandpass filters or by mathematically selecting areas
D 5769 Test Method for Determination of Benzene, Tolu- of the whole spectrum. A multivariate mathematical analysis
ene, and Total Aromatics in Finished Gasolines by Gas converts the detector response for the selected areas of the
Chromatography/Mass Spectrometry spectrum of an unknown to a concentration of benzene.
D 5842 Practice for Sampling and Handling of Fuels for
4 5. Significance and Use
Volatility Measurements
5.1 Benzene is a compound that endangers health, and the
D 5854 Practice for Mixing and Handling of Liquid
Samples of Petroleum and Petroleum Products concentration is limited by environmental protection agencies
to produce a less toxic gasoline.
E 168 Practices for General Techniques of Infrared Quanti-
tative Analysis 5.2 This test method is fast, simple to run, and inexpensive.
5.3 This test method is applicable for quality control in the
E 1655 Practices for Infrared Multivariate Quantitative
Analysis production and distribution of spark-ignition engine fuels.
6. Interferences
This test method is under the jurisdiction of ASTM Committee D-2 on
Petroleum Products and Lubricants and is the direct responsibility of Subcommittee 6.1 The primary spectral interferences are toluene and other
D02.04 on Hydrocarbon Analysis.
monosubstituted aromatics. In addition, oxygenates can inter-
Current edition approved April 10, 1999. Published June 1999. Originally
fere with measurements made with filter apparatus. Proper
published as D 6277 — 98. Last previous edition D 6277 — 98.
choice of the apparatus, proper design of a calibration matrix,
Annual Book of ASTM Standards, Vol 05.01.
Annual Book of ASTM Standards, Vol. 05.02.
and proper utilization of multivariate calibration techniques
Annual Book of ASTM Standards, Vol. 05.03.
can minimize these interferences.
Annual Book of ASTM Standards, Vol. 03.06.
D 6277
7. Apparatus
ATR element material ZnSe
beam condensing optics conical, non-focussing optics
7.1 Mid-IR Spectrometric Analyzer (of one of the following
integral to cell body
element configuration circular cross section with
types):
coaxial conical ends
7.1.1 Filter-based Mid-IR Test Apparatus—The type of
cone half angle 60°
element length 1.55 in.
apparatus suitable for use in this test method minimally
element diameter 0.125 in.
employes an IR source, an infrared transmission cell or a liquid
angle of incidence at
attenuated total internal reflection cell, wavelength discrimi- sample interface 53.8°
maximum range of
nating filters, a chopper wheel, a detector, an A-D converter, a
incidence angles +/– 1.5°
microprocessor, and a method to introduce the sample. The
standard absorbance
(1428 cm−1 band of acetone) 0.38 +/– 0.02 AU
frequencies and bandwidths of the filters are specified in Table
material of construction 316 stainless steel
1.
seals Chemraz or Kalraz o-rings
7.1.2 Fourier Transform Mid-IR Spectrometer—The type of
8. Reagents and Materials (see Note 1 and Note 2)
apparatus suitable for use in this test method employs an IR
8.1 Standards for Calibration, Qualification, and Quality
source, an infrared transmission cell or a liquid attenuated total
Control Check Standards—Use of chemicals of at least 99 %
internal reflection cell, a scanning interferometer, a detector, an
purity, where available, for quality control checks is required
A-D converter, a microprocessor, and a method to introduce
when preparing samples.
the sample. The following performance specifications (through
8.1.1 tert-Amyl methyl ether, TAME [994-05-8].
the ATR cell) must be met:
8.1.2 Benzene [1076-43-3].
–1
scan range 4000 to 600 cm
8.1.3 tert-Butyl ethyl ether, ETBE [637-92-3].
–1
resolution 4 cm
–1 8.1.4 tert-Butyl methyl ether, MTBE [1634-04-4].
S/N at 674 cm >300:1 RMS
8.1.5 1,3 Dimethylbenzene (m-xylene).
The signal to noise level will be established by taking a
8.1.6 Ethanol [64-17-5].
single beam spectrum using air or nitrogen as the reference and
8.1.7 Ethylbenzene [100-41-4].
declaring that spectrum as the background. The background
8.1.8 3–Ethyltoluene [620-14-4].
single beam spectrum obtained can be the average of multiple
8.1.9 Heavy aromatic/reformate petroleum stream (high
FTIR scans, but the total collection time shall not exceed 60 s. boiling cut: IPB of 150 +/− 5° C and EP of 245 +/− 8° C)
If interference from water vapor or carbon dioxide is a certified to contain less than 0.025 % benzene (an absorbance
−1
of less than 0.03 at 675 cm using a 0.2 mm cell and a baseline
problem, the instrument shall be purged with dry air or
−1 −1
between approximately 680 cm and 670 cm ) [64741-68-0].
nitrogen. A subsequent single beam spectrum shall be taken
8.1.10 Hexane (an absorbance versus water of less than 0.1
under the same conditions and ratioed to the background
at 250 nm using a 1cm cell) [110-54-3].
spectrum. The RMS noise of the ratioed spectra, the 100 %
8.1.11 2,2,4-Trimethylpentane (isooctane) [540-84-1].
line, shall not exceed 0.3 % transmittance in the region from
–1
8.1.12 Pentane (an absorbance versus water of less than 0.1
700 to 664 cm .
at 250 nm usinga1cm cell) [109-66-0].
7.2 Absorption Cell— The absorption cell can be either
8.1.13 Propylbenzene [103-65-1].
transmission or attenuated total reflectance.
8.1.14 Toluene [108-88-3].
7.2.1 Transmission Cells, shall have windows of potassium
8.1.15 1,3,5-Trimethylbenzene (mesitylene) [108-67-8].
bromide, zinc selenide, or other material having a significant
8.1.16 m-Xylene [108-38-3].
–1 –1
transmission from 712 cm to 660 cm . The cell path length
NOTE 1—Warning: These materials are flammable and may be harmful
of the transmission cell shall be 0.025 (+/–0.005) mm. The use
if ingested or inhaled.
of a wedged transmission cell with the same nominal path
NOTE 2—Only some of the reagents are required in each calibration or
length is acceptable.
qualification procedure.
7.2.2 Attenuated Total Reflectance (ATR) Cells, shall have
9. Sampling and Sample Handling
the following specifications:
9.1 General Requirements:
9.1.1 The sensitivity of the measurement of benzene to the
loss of benzene or other components through evaporation and
the resulting changes in composition is such that the utmost
TABLE 1 Specification for Filters Used in Filter-based Mid-IR
precaution and the most meticulous care in the drawing and
Test
handling of samples is required.
Center Wavenumber Bandwidth (in wavelength units)
9.1.2 Fuel samples to be analyzed by the test method shall
(+/− 0.15 % of wavenumber) (full width at half height)
-1
be sampled using procedures outlined in Practices D 4057,
673 cm 1% of l
c
-1
729 cm 1% of l
D 4177, or D 5842, where appropriate. Do not use the “Sam-
c
-1
769 cm 1% of l
c
pling by Water Displacement.” With some alcohol containing
-1
1205 cm 1% of l
c
-1
samples, the alcohol will dissolve in the water phase.
1054 cm 1% of l
c
-1
1188 cm 1% of l
c 9.1.3 Protect samples from excessive temperatures prior to
-1
1117 cm 1% of l
c
testing. This can be accomplished by storage in an appropriate
D 6277
ice bath or refrigerator at 0 to 5°C. prepared in accordance with Practice D 4307 or appropriately
9.1.4 Do not test samples stored in leaky containers. Discard scaled for larger blends and Practices D 5842 and D 5854,
and obtain a new sample if leaks are detected.
where appropriate. Whenever possible, use chemicals of at
9.2 Sample Handling During Analysis:
least 99 % purity. To minimize the evaporation of light
9.2.1 When analyzing samples by the mid infrared appara-
components, chill all chemicals and fuels used to prepare
tus, the sample must be between a temperature of 15 to 38° C.
standards.
Equilibrate all samples to the temperature of the laboratory (15
10.1.1 Calibration Matrix for Filter Based Mid IR
to 38°C) prior to analysis by this test method.
Instruments—Prepare the set of calibration standards as de-
9.2.2 After analysis, if the sample is to be saved, reseal the
fined in Table 2.
container and store the sample in an ice bath or a refrigerator
at 0 to 5°C.
10. Calibration and Standardization of the Apparatus
10.1 Calibration Matrix—Calibration standards shall be
TABLE 2 Filter Based Mid IR Instrument Calibration Sample Set (mass %)
B
Hvy. C C
5 6
Sample Benzene Toluene Xylenes MTBE EtOH TAME ETBE Isooctane
A
Ref.
1 0.00 2.50 12.5 5.00 0.00 00.0 20.0 0.00 30.0 30.0
2 0.00 2.50 25.0 2.50 0.00 0.00 0.00 0.00 35.0 35.0
3 0.00 5.00 7.50 10.0 1.00 0.00 2.50 15.0 25.0 34.0
4 0.00 12.5 12.5 3.00 20.0 0.00 2.50 0.00 25.0 24.5
5 0.00 20.0 10.0 1.00 0.00 10.00 0.00 0.00 25.0 34.0
6 0.00 25.0 7.50 2.50 0.00 0.00 0.00 0.00 40.0 25.0
7 0.00 25.0 2.50 7.50 0.00 4.00 0.00 0.00 20.0 41.0
8 0.25 0.00 10.0 5.00 0.00 0.00 0.00 20.00 25.0 39.75
9 0.25 2.50 6.00 2.50 0.00 0.00 0.00 0.00 35.0 53.75
10 0.25 4.75 15.0 1.00 0.00 7.50 0.00 0.00 25.0 46.50
11 0.25 10.0 0.00 10.0 15.00 0.00 0.00 0.00 30.0 34.75
12 0.25 14.0 7.50 3.00 0.00 5.00 0.00 0.00 30.0 40.25
13 0.50 2.50 12.5 5.00 5.00 0.00 5.00 5.00 20.0 44.5
14 0.50 5.00 10.0 2.00 0.00 0.00 0.00 0.00 30.0 42.5
15 0.50 6.00 7.50 7.50 0.00 0.00 20.0 0.00 25.0 33.5
16 0.50 10.0 15.0 2.50 0.00 12.5 0.00 0.00 25.0 34.5
17 0.50 12.5 4.00 7.50 0.00 0.00 0.00 20.0 20.0 35.5
18 0.50 25.0 10.0 1.00 0.00 0.00 0.00 0.00 25.0 38.5
19 0.75 5.00 25.0 1.00 0.00 0.00 0.00 0.00 30.0 38.25
20 0.75 10.0 10.0 5.00 0.00 0.00 0.00 0.00 30.0 44.25
21 0.75 12.5 0.00 10.0 0.00 5.00 0.00 0.00 35.0 36.75
22 0.75 12.5 12.5 1.00 0.00 0.00 0.00 0.00 30.0 43.25
23 0.75 25.0 20.0 10.0 0.00 0.00 0.00 0.00 14.25 30.0
24 1.00 15.00 25.0 1.00 7.50 0.00 15.0 2.50 10.0 23.0
25 1.00 5.00 7.50 10.0 0.00 2.00 0.00 0.00 35.0 39.5
26 1.00 7.50 10.0 7.50 20.00 0.00 0.00 0.00 20.0 34.0
27 1.00 10.0 10.0 5.00 0.00 10.0 0.00 0.00 30.0 34.0
28 1.00 15.0 2.00 2.5 15.0 0.00 2.50 7.50 20.0 37.0
29 1.00 25.0 20.0 0.00 0.00 0.00 0.00 0.00 25.0 29.0
30 1.50 5.00 15.0 5.00 5.00 0.00 10.00 5.00 20.0 33.5
31 1.50 15.0 15.0 1.00 0.00 0.00 5.00 20.0 20.0 22.5
32 1.50 15.0 15.0 1.00 0.00 0.00 0.00 0.00 30.0 37.5
33 1.50 10.0 5.00 7.50 0.00 7.50 0.00 2.50 25.0 41.0
34 1.50 25.0 10.0 0.00 0.00 0.00 0.00 0.00 25.0 38.5
35 2.00 5.00 7.50 2.50 7.50 0.00 2.50 2.00 30.0 41.0
36 2.00 5.00 20.0 0.00 0.00 0.00 0.00 0.00 30.0 43.0
37 2.00 12.5 12.5 5.00 0.00 8.00 0.00 0.00 25.00 35.0
38 2.00 25.0 5.00 3.00 20.00 0.00 0.00 0.00 20.0 25.0
39 2.00 25.0 20.0 0.00 0.00 0.00 0.00 0.00 20.0 33.0
40 2.50 0.00 15.0 2.50 0.00 0.00 15.0 0.00 25.0 40.0
41 2.50 5.00 5.00 10.0 15.0 0.00 0.00 0.00 25.0 37.5
42 2.50 15.0 0.00 7.50 0.00 10.0 0.00 0.00 30.0 35.0
43 2.50 10.0 15.0 2.5 0.00 0.00 0.00 15.0 25.0 30.0
44 2.50 20.0 20.0 3.00 0.00 0.00 0.00 0.00 25.0 29.5
45 3.00 5.00 25.0 5.00 0.00 0.00 7.50 7.50 20.0 27.0
46 3.00 10.0 15.0 5.00 0.00 7.50 0.00 7.50 20.0 32.0
47 3.00 15.0 5.00 2.00 2.50 0.00 10.0 2.50 25.0 35.0
48 3.00 20.0 20.0 5.00 0.00 0.00 0.00 0.00 25.0 27.0
49 3.00 25.0 10.0 2.00 0.00 0.00 0.00 0.00 30.0 30.0
50 4.00 0.00 20.0 2.50 0.00 5.00 0.00 0.00 25.0 43.5
51 4.00 2.50 5.00 10.0 5.00 0.00 5.00 5.00 25.0 38.5
52 4.00 15.0 2.50 5.00 2.00 10.0 2.00 0.00 20.0 39.5
53 4.00 20.0 15.0 2.00 0.00 0.00 0.00 0.00 25.0 34.0
D 6277
TABLE 2 Continued
B
Hvy. C C
5 6
Sample Benzene Toluene Xylenes MTBE EtOH TAME ETBE Isooctane
A
Ref.
54 4.00 25.0 20.0 1.00 0.00 0.00 0.00 0.00 25.0 25.0
55 5.00 5.00 25.00 4.00 0.00 0.00 0.00 0.00 25.0 36.0
56 5.00 7.50 5.00 7.50 0.00 0.00 0.00 15.0 25.0 35.0
57 5.00 12.5 12.5 2.50 15.0 0.00 0.00 0.00 20.0 32.5
58 5.00 20.0 5.00 5.00 0.00 5.00 0.00 0.00 25.0 35.0
59 5.00 20.0 2.50 2.50 0.00 0.00 7.50 0.00 25.0 37.5
60 5.00 25.0 20.0 0.00 0.00 0.00 0.00 0.00 20.0 30.0
A
Heavy reformate petroleum stream
B
50 volume % pentane in hexane
TABLE 4 FTIR Instruments PLS Calibration Sample Set B
10.1.1.1 Measure
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.