ASTM D5622-17

Standard Test Methods for Determination of Total Oxygen in Gasoline and Methanol Fuels by Reductive Pyrolysis

SIGNIFICANCE AND USE
4.1 These test methods cover the determination of total oxygen in gasoline and methanol fuels, and they complement Test Method D4815, which covers the determination of several specific oxygen-containing compounds in gasoline.  
4.2 The presence of oxygen-containing compounds in gasoline can promote more complete combustion, which reduces carbon monoxide emissions. The Clean Air Act (1992) requires that gasoline sold within certain specified geographical areas contain a minimum percent of oxygen by mass (presently 2.7 mass %) during certain portions of the year. The requirement can be met by blending compounds such as methyl tertiary butyl ether, ethyl tertiary butyl ether, and ethanol into the gasoline. These test methods cover the quantitative determination of total oxygen which is the regulated parameter.  
4.2.1 Only seven U.S. states have such wintertime requirements, and others with EPA approval have opted out of the program. The minimum oxygen limit now varies from 1.8 % to 3.5 % by mass. For methanol/heavier alcohol blend EPA waivers, the maximum oxygen content allowed is 3.5 % or 3.7 % by mass.
4.2.1.1 Only ethanol is used for such blending in the U.S. Ethers are banned by some states and are not used in all states because of water contamination issues.
SCOPE
1.1 These test methods cover the quantitative determination of total oxygen in gasoline and methanol fuels by reductive pyrolysis.  
1.2 Precision data are provided for 1.0 % to 5.0 % oxygen by mass in gasoline and for 40 % to 50 % oxygen by mass in methanol fuels.  
1.3 Several types of instruments can be satisfactory for these test methods. Instruments can differ in the way that the oxygen-containing species is detected and quantitated. However, these test methods are similar in that the fuel is pyrolyzed in a carbon-rich environment.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 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.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Apr-2017
• ICS: 75.160.20 - Liquid fuels
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.03 - Elemental Analysis

Relations

• Replaces: ASTM D5622-16 - Standard Test Methods for Determination of Total Oxygen in Gasoline and Methanol Fuels by Reductive Pyrolysis
• Effective Date: 01-May-2017
• Refers: ASTM D1298-12a - Standard Test Method for Density, Relative Density (Specific Gravity), or API Gravity of Crude Petroleum and Liquid Petroleum Products by Hydrometer Method
• Effective Date: 15-May-2012
• Refers: ASTM D1298-12 - Standard Test Method for Density, Relative Density (Specific Gravity), or API Gravity of Crude Petroleum and Liquid Petroleum Products by Hydrometer Method
• Effective Date: 01-Apr-2012
• Refers: ASTM D4057-06(2011) - Standard Practice for Manual Sampling of Petroleum and Petroleum Products
• Effective Date: 01-Jun-2011
• Refers: ASTM D4815-09 - Standard Test Method for Determination of MTBE, ETBE, TAME, DIPE, tertiary-Amyl Alcohol and C₁ to C₄ Alcohols in Gasoline by Gas Chromatography
• Effective Date: 01-Oct-2009
• Refers: ASTM D1298-99(2005) - Standard Test Method for Density, Relative Density (Specific Gravity), or API Gravity of Crude Petroleum and Liquid Petroleum Products by Hydrometer Method
• Effective Date: 01-Nov-2005
• Refers: ASTM D4815-03 - Standard Test Method for Determination of MTBE, ETBE, TAME, DIPE, tertiary-Amyl Alcohol and C₁ to C₄ Alcohols in Gasoline by Gas Chromatography
• Effective Date: 10-May-2003
• Refers: ASTM D4057-95(2000) - Standard Practice for Manual Sampling of Petroleum and Petroleum Products
• Effective Date: 10-Apr-2000
• Refers: ASTM D4815-99 - Standard Test Method for Determination of MTBE, ETBE, TAME, DIPE, <I>tertiary</I>-Amyl Alcohol and C₁ to C₄ Alcohols in Gasoline by Gas Chromatography
• Effective Date: 10-Nov-1999
• Refers: ASTM D4815-99e1 - Standard Test Method for Determination of MTBE, ETBE, TAME, DIPE, <I>tertiary</I>-Amyl Alcohol and C₁ to C₄ Alcohols in Gasoline by Gas Chromatography
• Effective Date: 10-Nov-1999
• Refers: ASTM D1298-99e2 - Standard Test Method for Density, Relative Density (Specific Gravity), or API Gravity of Crude Petroleum and Liquid Petroleum Products by Hydrometer Method
• Effective Date: 10-Jun-1999
• Refers: ASTM D1298-99 - Standard Test Method for Density, Relative Density (Specific Gravity), or API Gravity of Crude Petroleum and Liquid Petroleum Products by Hydrometer Method
• Effective Date: 10-Jun-1999
• Refers: ASTM D1298-99e1 - Standard Test Method for Density, Relative Density (Specific Gravity), or API Gravity of Crude Petroleum and Liquid Petroleum Products by Hydrometer Method
• Effective Date: 10-Jun-1999
• Refers: ASTM D4052-96(2002)e1 - Standard Test Method for Density and Relative Density of Liquids by Digital Density Meter
• Effective Date: 10-Apr-1996
• Referred By: ASTM D7455-19 - Standard Practice for Sample Preparation of Petroleum and Lubricant Products for Elemental Analysis
• Effective Date: 01-May-2017

Overview

ASTM D5622-17: Standard Test Methods for Determination of Total Oxygen in Gasoline and Methanol Fuels by Reductive Pyrolysis establishes reliable procedures for accurately determining total oxygen content in gasoline and methanol fuels. These test methods support regulatory requirements, such as those outlined in the Clean Air Act, which mandate minimum oxygen content in fuels to promote more complete combustion and reduce harmful emissions. By complementing ASTM D4815, which provides methods for specific oxygen compounds, ASTM D5622-17 addresses the quantitative analysis of overall oxygen levels, a key regulated parameter.

Key Topics

• Scope and Relevance

  • Designed for use in the petroleum industry, regulatory compliance, and environmental monitoring.
  • Applicable to gasoline and methanol fuels with oxygen content ranging from 1.0% to 5.0% by mass (gasoline) and 40% to 50% by mass (methanol fuels).
  • Ensures uniformity and accuracy in analyzing both blended and pure fuel samples.

• Test Method Principles

  • Involves reductive pyrolysis of the fuel sample in a carbon-rich environment, converting oxygen into measurable carbon monoxide.
  • Utilizes several instrument configurations for detection and quantification, including various carrier gases and detectors (thermal conductivity, infrared, coulometric).

• Regulatory Context

  • Supports adherence to national environmental standards such as the Clean Air Act.
  • Helps fuel suppliers meet minimum or maximum oxygen content regulations, varying by location and season.

• Precision and Reliability

  • Offers precision data validated through interlaboratory studies.
  • Specifies repeatability and reproducibility thresholds, ensuring test results are both reliable and consistent across laboratories.

Applications

• Quality Assurance in Fuel Production

  • Ensures manufactured gasoline and methanol blends meet specified oxygen content requirements before distribution.
  • Enables compliance with regulations limiting or mandating oxygenate blending, such as ethanol or MTBE.

• Regulatory Compliance Testing

  • Essential for fuel producers and suppliers to demonstrate conformity with EPA and Clean Air Act requirements.
  • Supports monitoring and reporting for jurisdictions with special oxygenate mandates during winter months or in specified regions.

• Environmental Impact Assessment

  • Facilitates evaluation of fuel combustion characteristics linked to emissions reduction strategies.
  • Supports research and policy initiatives aimed at improving air quality by monitoring oxygenate usage.

• Laboratory and Industrial Use

  • Applicable to process control, research and development, and post-production quality checks within refineries and independent laboratories.

Related Standards

• ASTM D4815: Methods for determining specific oxygenates (MTBE, ETBE, TAME, DIPE, ethanol, and other C1 to C4 alcohols) in gasoline.
• ASTM D1298: Test method for density, relative density, or API gravity by hydrometer.
• ASTM D4052: Density and API gravity determination by digital density meter.
• ASTM D4057 & D4177: Guidelines for manual and automatic sampling of petroleum and petroleum products.

Practical Value

Implementing ASTM D5622-17 benefits fuel producers, laboratories, and regulatory agencies through:

• Standardized, reproducible testing of oxygen content in a range of fuel types.
• Assured regulatory compliance with varying oxygen content limits in gasoline and methanol blends.
• Improved environmental and combustion performance data to guide fuel formulation and distribution.
• Consistency in results across different laboratories and analytical equipment, supporting global trade and quality assurance.

Keywords: ASTM D5622-17, total oxygen determination, gasoline, methanol fuels, reductive pyrolysis, fuel oxygenates, regulatory compliance, Clean Air Act, oxygen content testing, petroleum analysis.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D5622 − 17
Standard Test Methods for
Determination of Total Oxygen in Gasoline and Methanol
Fuels by Reductive Pyrolysis
This standard is issued under the fixed designation D5622; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* ucts by Hydrometer Method
D4052Test Method for Density, Relative Density, and API
1.1 These test methods cover the quantitative determination
Gravity of Liquids by Digital Density Meter
of total oxygen in gasoline and methanol fuels by reductive
D4057Practice for Manual Sampling of Petroleum and
pyrolysis.
Petroleum Products
1.2 Precision data are provided for 1.0% to 5.0% oxygen
D4177Practice for Automatic Sampling of Petroleum and
by mass in gasoline and for 40% to 50% oxygen by mass in
Petroleum Products
methanol fuels.
D4815Test Method for Determination of MTBE, ETBE,
1.3 Several types of instruments can be satisfactory for TAME, DIPE, tertiary-Amyl Alcohol and C to C Alco-
1 4
hols in Gasoline by Gas Chromatography
these test methods. Instruments can differ in the way that the
oxygen-containing species is detected and quantitated.
2.2 Other Standards:
However, these test methods are similar in that the fuel is
Clean Air Act (1992)
pyrolyzed in a carbon-rich environment.
3. Summary of Test Method
1.4 The values stated in SI units are to be regarded as
3.1 Afuel specimen of 1µLto 10µLis injected by syringe
standard. No other units of measurement are included in this
into a 950°C to 1300°C high-temperature tube furnace that
standard.
containsmetallizedcarbon.Oxygen-containingcompoundsare
1.5 This standard does not purport to address all of the
pyrolyzed, and the oxygen is quantitatively converted into
safety concerns, if any, associated with its use. It is the
carbon monoxide.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica- 3.2 A carrier gas, such as nitrogen, helium, or a helium/
bility of regulatory limitations prior to use. hydrogen mixture, sweeps the pyrolysis gases into any of four
1.6 This international standard was developed in accor- downstream systems of reactors, scrubbers, separators, and
dance with internationally recognized principles on standard- detectors for the determination of the carbon monoxide
ization established in the Decision on Principles for the content, hence of the oxygen in the original fuel sample. The
Development of International Standards, Guides and Recom- result is reported as mass % oxygen in the fuel.
mendations issued by the World Trade Organization Technical
4. Significance and Use
Barriers to Trade (TBT) Committee.
4.1 These test methods cover the determination of total
2. Referenced Documents
oxygen in gasoline and methanol fuels, and they complement
TestMethodD4815,whichcoversthedeterminationofseveral
2.1 ASTM Standards:
specific oxygen-containing compounds in gasoline.
D1298Test Method for Density, Relative Density, or API
Gravity of Crude Petroleum and Liquid Petroleum Prod-
4.2 Thepresenceofoxygen-containingcompoundsingaso-
line can promote more complete combustion, which reduces
carbonmonoxideemissions.TheCleanAirAct(1992)requires
These test methods are under the jurisdiction of Committee D02 on Petroleum
that gasoline sold within certain specified geographical areas
Products, Liquid Fuels, and Lubricants and are the direct responsibility of
contain a minimum percent of oxygen by mass (presently
Subcommittee D02.03 on Elemental Analysis.
Current edition approved May 1, 2017. Published May 2017. Originally 2.7mass %) during certain portions of the year. The require-
approved in 1994. Last previous edition approved in 2016 as D5622–16. DOI:
ment can be met by blending compounds such as methyl
10.1520/D5622-17.
tertiary butyl ether, ethyl tertiary butyl ether, and ethanol into
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. Federal Register, Vol 57, No. 24, Feb. 5, 1992, p. 4408.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5622 − 17
the gasoline. These test methods cover the quantitative deter- and water vapor. A reactor containing cupric oxide at 325°C
mination of total oxygen which is the regulated parameter. oxidizesthecarbonmonoxidetocarbondioxide,whichinturn
4.2.1 Only seven U.S. states have such wintertime is transported into a coulometric carbon dioxide detector.
requirements, and others with EPAapproval have opted out of Coulometrically generated base titrates the acid formed by
the program. The minimum oxygen limit now varies from reacting carbon dioxide with monoethanolamine.
1.8% to 3.5 % by mass. For methanol/heavier alcohol blend
5.2 Atechnique must be established to make a quantitative
EPA waivers, the maximum oxygen content allowed is 3.5%
introduction of the test specimen into the analyzer. Specimen
or 3.7 % by mass.
vials and transfer labware must be clean and dry.
4.2.1.1 Only ethanol is used for such blending in the U.S.
5.3 For instruments that measure carbon monoxide only,
Ethers are banned by some states and are not used in all states
pyrolysis conditions must be established to quantitatively
because of water contamination issues.
convert oxygen to carbon monoxide.
5. Apparatus
5.4 A system of scrubbers and separators must be estab-
4,5,6,7,8
lished to effectively remove pyrolysis products that interfere
5.1 Oxygen Elemental Analyzer —Avariety of instru-
with the detection of carbon monoxide or carbon dioxide, or
mentation can be satisfactory. However, the instrument must
both.
reductively pyrolize the specimen and convert oxygen to
carbon monoxide.
5.5 The detector responses must be linear with respect to
4,8
5.1.1 Test Method A —Helium carrier gas transports the
concentration, or nonlinear responses must be detectable and
pyrolysis products through a combination scrubber to remove
accurately related to concentration.
acidicgasesandwatervapor.Theproductsarethentransported
5.6 Selected items are available from the instrument manu-
to a molecular sieve gas chromatographic column where the
facturer.
carbon monoxide is separated from the other pyrolysis prod-
5.6.1 Pyrolysis tubes,
ucts.Athermal conductivity detector generates a response that
5.6.2 Scrubber tubes, and
is proportional to the amount of carbon monoxide.
5,8 5.6.3 Absorber tubes.
5.1.2 Test Method B —Nitrogen carrier gas transports the
pyrolysis products through a scrubber to remove water vapor.
6. Reagents
The pyrolysis products then flow through tandem infrared
6.1 Purity of Reagents —Reagent-grade chemicals shall be
detectors that measure carbon monoxide and carbon dioxide,
used in all tests. Unless otherwise indicated, it is intended that
respectively.
6,8 all reagents conform to the specifications of the Committee on
5.1.3 Test Method C —Amixture of helium and hydrogen
Analytical Reagents of theAmerican Chemical Society where
(95:5%), helium, or argon transports the pyrolysis products
such specifications are available. Other grades may be used,
throughtworeactorsinseries.Thefirstreactorcontainsheated
provided it is first ascertained that the reagent is of sufficiently
copper which removes sulfur-containing products. The second
high purity to permit its use without lessening the accuracy of
reactor contains a scrubber which removes acidic gases and a
the determination.
reactant which oxidizes carbon monoxide to carbon dioxide
(optional). The product gases are then homogenized in a 6.2 Calibration Standards:
mixing chamber, which maintains the reaction products at 6.2.1 Anhydrous methanol, 99.8% minimum assay, can be
absolute conditions of temperature, pressure, and volume. The used to calibrate the instrument for the analysis of methanol
mixing chamber is subsequently depressurized through a fuels.
column that separates carbon monoxide (or carbon dioxide, if 6.2.2 Isooctane, or other hydrocarbons, can be used as the
operating in the oxidation mode) from interfering compounds. blank provided the purity is satisfactory.
A thermal conductivity detector measures a response propor-
6.3 The instrument manufacturers require additional re-
tional to the amount of carbon monoxide or carbon dioxide.
agents.
7,8
4,8
5.1.4 Test Method D —Nitrogen carrier gas transports the
6.3.1 Test Method A:
pyrolysis products through scrubbers to remove acidic gases
6.3.1.1 Anhydrone (anhydrous magnesium perchlorate),
6.3.1.2 Ascarite II (sodium hydroxide on silica),
6.3.1.3 Helium carrier gas, 99.995% pure,
The sole source of supply of the apparatus (Thermo Scientific formerly known
6.3.1.4 Molecular sieve, 5Å, 60 to 80 mesh,
as Carlo Erba Models 1108, 1110, now FLASH 1112 and FLASH 2000) known to
the committee at this time is CE Elantech, Inc., 170 Oberlin Ave. N., Ste 5,
6.3.1.5 Nickel wool,
Lakewood, NJ 08701.
6.3.1.6 Nickelized carbon, 20% loading,
Thesolesourceofsupplyoftheapparatus(LecoModelRO-478)knowntothe
6.3.1.7 Quartz chips, and
committee at this time is Leco Corp., 3000 Lakeview Ave., St. Joseph, MI 49085.
6.3.1.8 Quartz wool.
The sole source of supply of the apparatus (Perkin-Elmer Series 2400) known
to the committee at this time is Perkin-Elmer Corp., 761 Main Ave., Norwalk, CT
06859.
7 9
Thesolesourceofsupplyoftheapparatus(UIC,Inc./CoulometricsModel5012 Reagent Chemicals, American Chemical Society Specifications, American
CO coulometer and Model 5220 autosampler-furnace) known to the committee at Chemical Society, Washington, DC. For Suggestions on the testing of reagents not
this time is UIC Inc., Box 863, Joliet, IL 60434. listed by the American Chemical Society, see Annual Standards for Laboratory
If you are aware of alternative suppliers, please provide this information to Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
ASTM International Headquarters. Your comments will receive careful consider- and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
ation at a meeting of the responsible technical committee, which you may attend. MD.
D5622 − 17
5,8
6.3.2 Test Method B: where:
6.3.2.1 Anhydrone (anhydrous magnesium perchlorate),
C = mass% oxygen in the calibration standard,
std
6.3.2.2 Carbon pyrolysis pellets, and
M = mass of the calibration standard, mg,
std
= volume of the calibration standard (µL)×density of
6.3.2.3 Nitrogen carrier gas, 99.99% pure.
6,8
the calibration standard (g/mL), and
6.3.3 Test M
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D5622 − 16 D5622 − 17
Standard Test Methods for
Determination of Total Oxygen in Gasoline and Methanol
Fuels by Reductive Pyrolysis
This standard is issued under the fixed designation D5622; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 These test methods cover the quantitative determination of total oxygen in gasoline and methanol fuels by reductive
pyrolysis.
1.2 Precision data are provided for 1.0 % to 5.0 % oxygen by mass in gasoline and for 40 % to 50 % oxygen by mass in
methanol fuels.
1.3 Several types of instruments can be satisfactory for these test methods. Instruments can differ in the way that the
oxygen-containing species is detected and quantitated. However, these test methods are similar in that the fuel is pyrolyzed in a
carbon-rich environment.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 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.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D1298 Test Method for Density, Relative Density, or API Gravity of Crude Petroleum and Liquid Petroleum Products by
Hydrometer Method
D4052 Test Method for Density, Relative Density, and API Gravity of Liquids by Digital Density Meter
D4057 Practice for Manual Sampling of Petroleum and Petroleum Products
D4177 Practice for Automatic Sampling of Petroleum and Petroleum Products
D4815 Test Method for Determination of MTBE, ETBE, TAME, DIPE, tertiary-Amyl Alcohol and C to C Alcohols in
1 4
Gasoline by Gas Chromatography
2.2 Other Standards:
Clean Air Act (1992)
3. Summary of Test Method
3.1 A fuel specimen of 1 μL to 10 μL is injected by syringe into a 950 °C to 1300 °C high-temperature tube furnace that contains
metallized carbon. Oxygen-containing compounds are pyrolyzed, and the oxygen is quantitatively converted into carbon
monoxide.
3.2 A carrier gas, such as nitrogen, helium, or a helium/hydrogen mixture, sweeps the pyrolysis gases into any of four
downstream systems of reactors, scrubbers, separators, and detectors for the determination of the carbon monoxide content, hence
of the oxygen in the original fuel sample. The result is reported as mass % oxygen in the fuel.
These test methods are under the jurisdiction of Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and are the direct responsibility of Subcommittee
D02.03 on Elemental Analysis.
Current edition approved June 1, 2016May 1, 2017. Published June 2016May 2017. Originally approved in 1994. Last previous edition approved in 20112016 as
D5622 – 95 (2011).D5622 – 16. DOI: 10.1520/D5622-16.10.1520/D5622-17.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Federal Register, Vol 57, No. 24, Feb. 5, 1992, p. 4408.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5622 − 17
4. Significance and Use
4.1 These test methods cover the determination of total oxygen in gasoline and methanol fuels, and they complement Test
Method D4815, which covers the determination of several specific oxygen-containing compounds in gasoline.
4.2 The presence of oxygen-containing compounds in gasoline can promote more complete combustion, which reduces carbon
monoxide emissions. The Clean Air Act (1992) requires that gasoline sold within certain,certain specified geographical areas
contain a minimum percent of oxygen by mass (presently 2.7 mass 2.7 mass %) during certain portions of the year. The
requirement can be met by blending compounds such as methyl tertiary butyl ether, ethyl tertiary butyl ether, and ethanol into the
gasoline. These test methods cover the quantitative determination of total oxygen which is the regulated parameter.
4.2.1 Only seven U.S. states have such wintertime requirements, and others with EPA approval have opted out of the program.
The minimum oxygen limit now varies from 1.8 % to 3.5 % by mass. For methanol/heavier alcohol blend EPA waivers, the
maximum oxygen content allowed is 3.5 % or 3.7 % by mass.
4.2.1.1 Only ethanol is used for such blending in the U.S. Ethers are banned by some states and are not used in all states because
of water contamination issues.
5. Apparatus
4,5,6,7,8
5.1 Oxygen Elemental Analyzer —A variety of instrumentation can be satisfactory. However, the instrument must
reductively pyrolize the specimen and convert oxygen to carbon monoxide.
4,8
5.1.1 Test Method A —Helium carrier gas transports the pyrolysis products through a combination scrubber to remove acidic
gases and water vapor. The products are then transported to a molecular sieve gas chromatographic column where the carbon
monoxide is separated from the other pyrolysis products. A thermal conductivity detector generates a response that is proportional
to the amount of carbon monoxide.
5,8
5.1.2 Test Method B —Nitrogen carrier gas transports the pyrolysis products through a scrubber to remove water vapor. The
pyrolysis products then flow through tandem infrared detectors that measure carbon monoxide and carbon dioxide, respectively.
6,8
5.1.3 Test Method C —A mixture of helium and hydrogen (95:5 %), helium, or argon transports the pyrolysis products through
two reactors in series. The first reactor contains heated copper which removes sulfur-containing products. The second reactor
contains a scrubber which removes acidic gases and a reactant which oxidizes carbon monoxide to carbon dioxide (optional). The
product gases are then homogenized in a mixing chamber, which maintains the reaction products at absolute conditions of
temperature, pressure, and volume. The mixing chamber is subsequently depressurized through a column that separates carbon
monoxide (or carbon dioxide, if operating in the oxidation mode) from interfering compounds. A thermal conductivity detector
measures a response proportional to the amount of carbon monoxide or carbon dioxide.
7,8
5.1.4 Test Method D —Nitrogen carrier gas transports the pyrolysis products through scrubbers to remove acidic gases and
water vapor. A reactor containing cupric oxide at 325 °C oxidizes the carbon monoxide to carbon dioxide, which in turn is
transported into a coulometric carbon dioxide detector. Coulometrically generated base titrates the acid formed by reacting carbon
dioxide with monoethanolamine.
5.2 A technique must be established to make a quantitative introduction of the test specimen into the analyzer. Specimen vials
and transfer labware must be clean and dry.
5.3 For instruments that measure carbon monoxide only, pyrolysis conditions must be established to quantitatively convert
oxygen to carbon monoxide.
5.4 A system of scrubbers and separators must be established to effectively remove pyrolysis products that interfere with the
detection of carbon monoxide or carbon dioxide, or both.
5.5 The detector responses must be linear with respect to concentration, or nonlinear responses must be detectable and
accurately related to concentration.
5.6 Selected items are available from the instrument manufacturer.
5.6.1 Pyrolysis tubes,
5.6.2 Scrubber tubes, and
5.6.3 Absorber Tubes.tubes.
The sole source of supply of the apparatus (Thermo Scientific formerly known as Carlo Erba Models 1108, 1110, now FLASH 1112 and FLASH 2000) known to the
committee at this time is CE Elantech, Inc., 170 Oberlin Ave. N., Ste 5, Lakewood, NJ 08701.
The sole source of supply of the apparatus (Leco Model RO-478) known to the committee at this time is Leco Corp., 3000 Lakeview Ave., St. Joseph, MI 49085.
The sole source of supply of the apparatus (Perkin-Elmer Series 2400) known to the committee at this time is Perkin-Elmer Corp., 761 Main Ave., Norwalk, CT 06859.
The sole source of supply of the apparatus (UIC, Inc./Coulometrics Model 5012 CO coulometer and Model 5220 autosampler-furnace) known to the committee at this
time is UIC Inc., Box 863, Joliet, IL 60434.
If you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a
meeting of the responsible technical committee, which you may attend.
D5622 − 17
6. Reagents
6.1 Purity of Reagents —Reagent grade Reagent-grade chemicals shall be used in all tests. Unless otherwise indicated, it is
intended that all reagents conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society
where such specifications are available. Other grades may be used, provided it is first ascertained that the reagent is of sufficiently
high purity to permit its use without lessening the accuracy of the determination.
6.2 Calibration Standards:
6.2.1 NIST SRM 1837, which contains certified concentrations of methanol and t-butanol in reference fuel, can be used to
calibrate the instrument for the analysis of oxygenates in gasoline.
6.2.1 Anhydrous methanol, 99.8 % minimum assay, can be used to calibrate the instrument for the analysis of methanol fuels.
6.2.2 Isooctane, or other hydrocarbons, can be used as the blank provided the purity is satisfactory.
6.3 Quality Control Standard—NIST SRM 1838 can be used to check the accuracy of the calibration.
6.3 The instrument manufacturers require additional reagents.
4,84,8
6.3.1 Test Method A:
6.3.1.1 Anhydrone (anhydrous magnesium perchlorate),
6.3.1.2 Ascarite II (sodium hydroxide on silica),
6.3.1.3 Helium carrier gas, 99.995 % pure,
6.3.1.4 Molecular sieve, 5Å, 60 to 80 mesh,
6.3.1.5 Nickel wool,
6.3.1.6 Nickelized carbon, 20 % loading,
6.3.1.7 Quartz chips, and
6.3.1.8 Quartz wool.
5,8
6.3.2 Test Method B:
6.3.2.1 Anhydrone (anhydrous magnesium perchlorate),
6.3.2.2 Carbon pyrolysis pellets, and
6.3.2.3 Nitrogen carrier gas, 99.99 % pure.
6,8
6.3.3 Test Method C:
6.3.3.1 Anhydrone (anhydrous magnesium perchlorate),
6.3.3.2 Ascarite II (sodium hydroxide on silica),
6.3.3.3 Carrier gas, either helium (95 %) ⁄hydrogen (5 %), mixture, 99.99 % pure; helium, 99.995 % pure; or argon, 99.98 %
pure,
6.3.3.4 Copper plus, wire form, and
6.3.3.5 Platinized carbon.
7,8
6.3.4 Test Method D:
6.3.4.1 Anhydrone (anhydrous magnesium perchlorate),
6.3.4.2 Ascarite II (sodium hydroxide on silica),
6.3.4.3 Copper (II) oxide,
6.3.4.4 Coulometric cell solutions, including a cathode solution of monoethanolamine in dimethyl sulfoxide and an anode
solution of water and potassium
...