ASTM D8086-20

Standard Test Method for Determination of Methanol and Ethanol in Electrical Insulating Liquids of Petroleum Origin by Headspace (HS)-Gas Chromatography (GC) Using Mass Spectrometry (MS) or Flame Ionization Detection (FID)

SIGNIFICANCE AND USE
5.1 Methanol and ethanol are generated by the degradation of cellulosic materials used in the solid insulation systems of electrical equipment. More particularly, methanol comes from the depolymerization of cellulosic materials.3, 4, 5, 6  
5.2 Methanol and ethanol, which are soluble in an insulating liquid to an appreciable degree, will proportionally migrate to that liquid after being produced from the cellulose.  
5.3 High concentrations or unusual increases in the concentrations of methanol or ethanol, or both, in an insulating liquid may indicate cellulose degradation from aging or incipient fault conditions. Testing for these alcohols may be used to complement dissolved gas-in-oil analysis and furanic compounds as performed in accordance with Test Methods D3612 and D5837 respectively.
SCOPE
1.1 This test method describes the determination of by-products of cellulosic materials degradation found in electrical insulation systems that are immersed in insulating liquid. Such materials include paper, pressboard, wood and cotton materials. This test method allows the analysis of methanol and ethanol from the sample matrix by headspace GC-MS or GC-FID.  
1.2 This test method has been used to test for methanol and ethanol in mineral insulating liquids and less flammable electrical insulating liquids of mineral origin as defined in D3487 and D5222 respectively. Currently, this method is not a practical application for ester liquids.  
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 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-Nov-2020
• ICS: 29.040.10 - Insulating oils
• Technical Committee: D27 - Electrical Insulating Liquids and Gases
• Drafting Committee: D27.03 - Analytical Tests

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: D8086 − 20
Standard Test Method for
Determination of Methanol and Ethanol in Electrical
Insulating Liquids of Petroleum Origin by Headspace (HS)-
Gas Chromatography (GC) Using Mass Spectrometry (MS)
1
or Flame Ionization Detection (FID)
This standard is issued under the fixed designation D8086; 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 D3487Specification for Mineral Insulating Oil Used in
Electrical Apparatus
1.1 This test method describes the determination of by-
D3612Test Method for Analysis of Gases Dissolved in
products of cellulosic materials degradation found in electrical
Electrical Insulating Oil by Gas Chromatography
insulation systems that are immersed in insulating liquid. Such
D5222Specification for High Fire-Point Mineral Electrical
materials include paper, pressboard, wood and cotton materi-
Insulating Oils
als. This test method allows the analysis of methanol and
D5837Test Method for Furanic Compounds in Electrical
ethanol from the sample matrix by headspace GC-MS or
Insulating Liquids by High-Performance Liquid Chroma-
GC-FID.
tography (HPLC)
1.2 This test method has been used to test for methanol and
ethanol in mineral insulating liquids and less flammable
3. Terminology
electrical insulating liquids of mineral origin as defined in
D3487 and D5222 respectively. Currently, this method is not a
3.1 Definitions:
practical application for ester liquids.
3.1.1 extract ion mass spectrum, n—a record that shows a
1.3 The values stated in SI units are to be regarded as specific mass-to-charge ratio (m/z) extracted from a mass
standard. No other units of measurement are included in this spectrum.
standard.
3.1.2 mass spectrum, n—a record that shows the relative
1.4 This standard does not purport to address all of the
numberofionsofvariousmassthatareproducedwhenagiven
safety concerns, if any, associated with its use. It is the
substance is processed in a mass spectrometer.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
4. Summary of Test Method
mine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accor- 4.1 Analysis of methanol (CH OH) and ethanol (C H OH)
3 2 5
dance with internationally recognized principles on standard- inelectricalinsulatingliquidsconsistsofbringinganinsulating
ization established in the Decision on Principles for the liquid sample in contact with a gas phase (headspace) in a
Development of International Standards, Guides and Recom- closedvessel.Thedissolvedspeciescontainedintheinsulating
mendations issued by the World Trade Organization Technical
liquid are then equilibrated between the two phases in contact
Barriers to Trade (TBT) Committee.
under controlled conditions (according to Henry’s law). At
equilibrium, the headspace is over-pressurized with a carrier
2. Referenced Documents
gas and then the content of a loop is filled by the depressur-
2
2.1 ASTM Standards:
ization of the headspace against the ambient atmospheric
D923Practices for Sampling Electrical Insulating Liquids
pressure (see Note 1).
NOTE 1—Other headspace principles may also be used but need to be
1
This test method is under the jurisdiction of ASTM Committee D27 on
verified and the analytical performance may be somewhat different than
Electrical Insulating Liquids and Gases and is the direct responsibility of Subcom-
listed.
mittee D27.03 on Analytical Tests.
CurrenteditionapprovedDec.1,2020.PublishedFebruary2021.DOI:10.1520/
4.2 The gases contained in the loop or in the syringe are
D8086-20.
2 introduced into a gas chromatograph.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
4.3 Methanolandethanolinthetestspecimenarequantified
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. using calibration curves.
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D8086 − 20
TABLE 1 Instrumental Conditions for MS Detection
5. Significance and Use
Headspace Sampler parameters
5.1 Methanol and ethanol are generated by the degradation
Test Specimen Loop volume 0.5 mL
of cellulosic materials used in the solid insulation systems of
Shaking Power
...