ASTM D5845-95(2000)e1
(Test Method)Standard Test Method for Determination of MTBE, ETBE, TAME, DIPE, Methanol, Ethanol and tert-Butanol in Gasoline by Infrared Spectroscopy
Standard Test Method for Determination of MTBE, ETBE, TAME, DIPE, Methanol, Ethanol and <i>tert-</i>Butanol in Gasoline by Infrared Spectroscopy
SCOPE
1.1 This test method covers the determination of methanol, ethanol, tert-butanol, methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), and diisopropyl ether (DIPE) in gasoline by infrared spectroscopy. The test method is suitable for determining methanol from 0.1 to 6 mass %, ethanol from 0.1 to 11 mass %, tert-butanol from 0.1 to 14 mass %, and DIPE, MTBE, ETBE and TAME from 0.1 to 20 mass %.
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NOTICE: This standard has either been superseded and replaced by a new version or discontinued.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.
e1
Designation: D 5845 – 95 (Reapproved 2000) An American National Standard
Standard Test Method for
Determination of MTBE, ETBE, TAME, DIPE, Methanol,
Ethanol and tert-Butanol in Gasoline by Infrared
Spectroscopy
This standard is issued under the fixed designation D 5845; 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.
e NOTE—Editorial corrections were made throughout in November 2000.
1. Scope E 1655 Practice for Infrared, Multivariate, Quantitative
Analysis
1.1 This test method covers the determination of methanol,
2.2 Other Standard:
ethanol, tert-butanol, methyl tert-butyl ether (MTBE), ethyl
GC/OFID EPA Test Method—Oxygen and Oxygenate Con-
tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), and
tent Analysis (by way of gas chromatography with
diisopropyl ether (DIPE) in gasoline by infrared spectroscopy.
oxygen-selective flame ionization detection)
The test method is suitable for determining methanol from 0.1
to 6 mass %, ethanol from 0.1 to 11 mass %, tert-butanol from
3. Terminology
0.1 to 14 mass %, and DIPE, MTBE, ETBE and TAME from
3.1 Definitions:
0.1 to 20 mass %.
3.1.1 oxygenate, n—an oxygen-containing organic com-
1.2 SI units of measurement are preferred and used through-
pound, which may be used as a fuel or fuel supplement, for
out this standard.
example, various alcohols or ethers.
1.3 This standard does not purport to address all of the
3.1.2 multivariate calibration, n—a process for creating a
safety concerns, if any, associated with its use. It is the
calibration model in which multivariate mathematics is applied
responsibility of the user of this standard to establish appro-
to correlate the absorbances measured for a set of calibration
priate safety and health practices and determine the applica-
samples to reference component concentrations or property
bility of regulatory limitations prior to use.
values for the set of samples. The resultant multivariate
2. Referenced Documents calibration model is applied to the analysis of spectra of
unknown samples to provide an estimate of the component
2.1 ASTM Standards:
concentration or property values for the unknown sample.
D 1298 Practice for Density, Relative Density (Specific
Gravity), or API Gravity of Crude Petroleum and Liquid
4. Summary of Test Method
Petroleum Products by Hydrometer Method
4.1 A sample of gasoline is introduced into a liquid sample
D 4052 Test Method for Density and Relative Density of
3 cell. A beam of infrared light is imaged through the sample
Liquids by Digital Density Meter
onto a detector, and the detector response is determined.
D 4057 Practice for Manual Sampling of Petroleum and
3 Regions of the infrared spectrum are selected for use in the
Petroleum Products
analysis by either placing highly selective bandpass filters
D 4307 Practice for Preparation of Liquid Blends for Use as
3 before or after the sample or mathematically selecting the
Analytical Standards
regions after the whole spectrum is obtained. A multivariate
D 4815 Test Method for Determination of MTBE, ETBE,
mathematical analysis is carried out which converts the detec-
TAME, DIPE, tert-Amyl Alcohol, and C to C Alcohols
1 4
4 tor response for the selected regions in the spectrum of an
in Gasoline by Gas Chromatography
unknown to a concentration for each component.
D 5599 Test Method for Determination of Oxygenates in
Gasoline by Gas Chromatography and Oxygen Selective
5. Significance and Use
Flame Ionization Detection
5.1 Alcohols and ethers are added to gasoline to produce a
reformulated lower emissions gasoline. Alcohols and ethers
This test method is under the jurisdiction of ASTM Committee D02 on
may also be added to gasoline to increase the octane number.
Petroleum Products and Lubricants and is the direct responsibility of Subcommittee
D02.04.OF on Absorption Spectroscopic Methods.
Current edition approved Oct. 10, 1995. Published December 1995.
2 5
Annual Book of ASTM Standards, Vol 05.01. Annual Book of ASTM Standards, Vol 03.06.
3 6
Annual Book of ASTM Standards, Vol 05.02. Code of Federal Regulations, Part 80 of Title 40, Section 80.46(g); also
Annual Book of ASTM Standards, Vol 05.03. published in the Federal Register, Volume 59, No. 32, February 16, 1994, p 7828.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
D 5845
Type and concentration of various oxygenates are specified and 8. Sampling and Sample Handling
regulated to ensure acceptable commercial gasoline quality.
8.1 General Requirements:
Driveability, vapor pressure, phase separation, and evaporative
8.1.1 Gasoline samples must be handled with meticulous
emissions are some of the concerns associated with oxygenated
care to prevent evaporative loss and composition changes.
fuels.
8.1.2 Gasoline samples to be analyzed by the test method
5.2 This test method is faster, simpler, less expensive and
shall be obtained using method(s) specified by governmental
more portable than current methods.
regulatory agencies or by the procedures outlined in Practice
5.3 This test method may be applicable for quality control in
D 4057 (or equivalent). Do not use the “Sampling by Water
the production of gasoline.
Displacement” method as some alcohols or ethers might be
5.4 This test method is not suitable for testing for compli-
extracted into the water phase.
ance with federal regulations.
8.1.3 Protect samples from excessive temperatures prior to
5.5 False positive readings for some of the samples tested in
testing. This can be accomplished by storage in an appropriate
the round robin were sometimes observed. As only extreme
ice bath or refrigerator at 0 to 5°C.
base gasolines were tested in the round robin, no definitive
8.1.4 Do not test samples stored in leaky containers. Discard
statement can be made as to the expected frequency or
and obtain a new sample if leaks are detected.
magnitude of false positives expected in a wider range of base
8.1.5 Perform the oxygenate determination on fresh samples
gasolines.
from containers that are at least 80 % full. If sample containers
are less than 80 % full or have been opened and sampled
6. Apparatus
multiple times, a new sample shall be obtained.
6.1 Mid-IR Spectrometric Analyzer, of one of the following
8.2 Sample Handling During Analysis:
types:
8.2.1 Prior to the analysis of samples by infrared spectros-
6.1.1 Filter-based Mid-IR Test Apparatus—The type of
copy, the samples should be allowed to equilibrate to the
apparatus suitable for use in this test method minimally
temperature at which they should be analyzed (15 to 38°C).
employs an IR source, an infrared transmission cell or a liquid
8.2.2 After withdrawing the sample, reseal the container,
attenuated total internal reflection cell, wavelength discrimi-
and store the sample in an ice bath or a refrigerator at 0 to 5°C.
nating filters, a chopper wheel, a detector, an A-D converter, a
microprocessor, and a sample introduction system.
9. Preparation, Calibration, and Validation of
6.1.2 Fourier Transform Mid-IR Test Apparatus—The type
Calibration of the Infrared Test Apparatus
of apparatus suitable for use in this test method employs an IR
9.1 Preparation—Prepare the instrument for operation in
source, an infrared transmission cell or a liquid attenuated total
accordance with the manufacturer’s instructions.
internal reflection cell, a scanning interferometer, a detector, an
9.2 Calibration—Each instrument must be calibrated by the
A-D converter, a microprocessor and a sample introduction
manufacturer or user in accordance with Practice E 1655. This
system.
practice serves as a guide for the multivariate calibration of
6.1.3 Dispersive Mid-IR Test Apparatus—The type of appa-
infrared spectrometers used in determining the physical char-
ratus suitable for use in this test method minimally employs an
acteristics of petroleum and petrochemical products. The
IR source, an infrared transmission cell or a liquid attenuated
procedures describe treatment of the data, development of the
total internal reflection cell, a wavelength dispersive element
calibration, and validation of the calibration. Note that bias and
such as a grating or prism, a chopper wheel, a detector, an A-D
slope adjustments are specifically not recommended to im-
converter, a microprocessor and a sample introduction system.
prove calibration or prediction statistics for IR multivariate
models.
7. Reagents and Materials
9.3 Validation of Calibration—The calibration of the instru-
7.1 Standards for Calibration and Quality Control Check
ment must be validated in order to ensure that the instrument
Solutions—Use of chemicals of at least 99 % purity is highly
accurately and precisely measures each oxygenate in the
recommended when preparing calibration and quality control
presence of typical gasoline compounds or other oxygenates
check samples. If reagents of high purity are not available, an
that, in typical concentrations, present spectral interferences.
accurate assay of the reagent must be performed using a
General classes of compounds that will cause interferences
properly calibrated GC or other techniques (for example, water
include aromatics, branched aliphatic hydrocarbons, and other
determination).
oxygenates.
7.1.1 Base gasolines containing no oxygenates,
9.3.1 Preparation of Validation Standards—The minimum
7.1.2 Methanol,
matrix of validation standards is presented in Table 1. Addi-
7.1.3 Ethanol,
tional validation standards may be added. Prepare multicom-
7.1.4 tert-Butanol,
ponent validation standards of the oxygenates by mass accord-
7.1.5 Methyl tert-butyl ether, MTBE,
ing to Practice D 4307 or appropriately scaled for larger
7.1.6 Ethyl tert-butyl ether, ETBE,
blends. To ensure that there is minimum interference from any
7.1.7 tert-Amyl methyl ether, TAME, and
oxygenate present in the base gasolines, a gas chromatographic
7.1.8 Diisopropyl ether, DIPE. analysis of the base gasolines must be performed to ensu
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.