ASTM D6810-22

Standard Test Method for Measurement of Hindered Phenolic Antioxidant Content in Non-Zinc Turbine Oils by Linear Sweep Voltammetry

SIGNIFICANCE AND USE
5.1 The quantitative determination of hindered phenol antioxidants in a new turbine oil measures the amount of this material that has been added to the oil as protection against oxidation. Beside phenols, turbine oils can be formulated with other antioxidants such as amines which can extend the oil life. In used oil, the determination measures the amount of original (phenolic) antioxidant remaining after oxidation have reduced its initial concentration. This test method is not designed or intended to detect all of the antioxidant intermediates formed during the thermal and oxidative stressing of the oils, which are recognized as having some contribution to the remaining useful life of the used or in-service oil. Nor does it measure the overall stability of an oil, which is determined by the total contribution of all species present. Before making final judgment on the remaining useful life of the used oil, which might result in the replacement of the oil reservoir, it is advised to perform additional analytical techniques (in accordance with Practices D6224 and D4378), having the capability of measuring remaining oxidative life of the used oil.  
5.1.1 This test method is applicable to non-zinc turbine oils. These are refined mineral oils containing rust and oxidation inhibitors, but not antiwear additives. This test method has not yet been established with sufficient precision for antiwear oils.  
5.2 This test method is also suitable for manufacturing control and specification acceptance.  
5.3 When a voltammetric analysis is obtained for a turbine oil inhibited with a typical hindered phenol antioxidant, there is an increase in the current of the produced voltammogram between 3 s to 5 s (or 0.3 V to 0.6 V applied voltage) (see Note 1) in the basic test solution (Fig. 1—x-axis 1 second = 0.1 V). Hindered phenol antioxidants detected by voltammetric analysis include, but are not limited to, 2,6-di-tert-butyl-4-methylphenol; 2,6-di-tert-butylphenol and 4,4'-meth...
SCOPE
1.1 This test method covers the voltammetric determination of hindered phenol antioxidants in new or in-service non-zinc turbine oils in concentrations from 0.0075 % by weight up to concentrations found in new oils by measuring the amount of current flow at a specified voltage in the produced voltammogram.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 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-Jun-2022
• ICS: 75.100 - Lubricants, industrial oils and related products
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.09.0C - Oxidation of Turbine Oils

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: D6810 − 22
Standard Test Method for
Measurement of Hindered Phenolic Antioxidant Content in
1
Non-Zinc Turbine Oils by Linear Sweep Voltammetry
This standard is issued under the fixed designation D6810; 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* for Auxiliary Power Plant Equipment
D6447 Test Method for Hydroperoxide Number of Aviation
1.1 This test method covers the voltammetric determination
Turbine Fuels by Voltammetric Analysis
of hindered phenol antioxidants in new or in-service non-zinc
D6971 Test Method for Measurement of Hindered Phenolic
turbine oils in concentrations from 0.0075 % by weight up to
and Aromatic Amine Antioxidant Content in Non-zinc
concentrations found in new oils by measuring the amount of
Turbine Oils by Linear Sweep Voltammetry
current flow at a specified voltage in the produced voltammo-
gram.
3. Terminology
1.2 The values stated in SI units are to be regarded as
3.1 Definitions:
standard. No other units of measurement are included in this
3.1.1 See Terminology D4175 for a more extensive list of
standard.
terms used in this test method.
1.3 This standard does not purport to address all of the
3.1.2 electrolytic cell, n—an electrochemical cell in which
safety concerns, if any, associated with its use. It is the
chemicalreactionsarecausedbyapplyinganexternalpotential
responsibility of the user of this standard to establish appro-
difference greater than, and opposite to, the galvanic electro-
3
priate safety, health, and environmental practices and deter-
motive force of the cell. IUPAC
mine the applicability of regulatory limitations prior to use.
3.1.3 linear sweep voltammetry, n—a technique applied to
1.4 This international standard was developed in accor-
the monitoring of antioxidant additive content in lubricants,
dance with internationally recognized principles on standard-
where the current is detected as an applied potential is
ization established in the Decision on Principles for the
increased linearly over a period of time.
Development of International Standards, Guides and Recom-
3.1.4 voltammogram, n—the plot of current versus voltage.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
4. Summary of Test Method
4.1 A measured quantity of sample is dispensed into a vial
2. Referenced Documents
containing a measured quantity of alcohol-based electrolyte
2
2.1 ASTM Standards:
solution and containing a layer of sand. When the vial is
D1193 Specification for Reagent Water
shaken, the hindered phenol antioxidants and other solution
D4057 Practice for Manual Sampling of Petroleum and
soluble oil components present in the sample are extracted into
Petroleum Products
the solution and the remaining droplets suspended in the
D4175 Terminology Relating to Petroleum Products, Liquid
solution are agglomerated by the sand. The sand/droplet
Fuels, and Lubricants
suspension is allowed to settle out and the hindered phenol
D4378 Practice for In-Service Monitoring of Mineral Tur-
antioxidants dissolved in the solution are quantified by volta-
bine Oils for Steam, Gas, and Combined Cycle Turbines
mmetric analysis. The results are calculated and reported as
D6224 PracticeforIn-ServiceMonitoringofLubricatingOil
weight percent of antioxidant or as millimoles (mmol) of
antioxidant per litre of sample for prepared and fresh oils and
as a percent remaining antioxidant for used oils.
1
This test method is under the jurisdiction of ASTM Committee D02 on
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of
4.2 Voltammetric analysis is a technique that applies
Subcommittee D02.09.0C on Oxidation of Turbine Oils.
electro-analytic methods when a sample to be analyzed is
Current edition approved July 1, 2022. Published August 2022. Originally
approved in 2002. Last previous edition approved in 2021 as D6810 – 21. DOI: mixed with an electrolyte and a solvent and placed within an
10.1520/D6810-22.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
3
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Inczedy,J.,Lengyel,T.,andUre,A.M., Orange Book: IUPAC Compendium on
Standards volume information, refer to the standard’s Document Summary page on Analytical Nomenclature, Definitive Rules 1997, 3rd Edition, Blackwell Science,
the ASTM website. 1998.
*A Summary of Changes section appears at the end of t
...

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: D6810 − 21 D6810 − 22
Standard Test Method for
Measurement of Hindered Phenolic Antioxidant Content in
1
Non-Zinc Turbine Oils by Linear Sweep Voltammetry
This standard is issued under the fixed designation D6810; 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 This test method covers the voltammetric determination of hindered phenol antioxidants in new or in-service non-zinc turbine
oils in concentrations from 0.0075 % by weight up to concentrations found in new oils by measuring the amount of current flow
at a specified voltage in the produced voltammogram.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in 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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.4 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
2.1 ASTM Standards:
D1193 Specification for Reagent Water
D4057 Practice for Manual Sampling of Petroleum and Petroleum Products
D4175 Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
D4378 Practice for In-Service Monitoring of Mineral Turbine Oils for Steam, Gas, and Combined Cycle Turbines
D6224 Practice for In-Service Monitoring of Lubricating Oil for Auxiliary Power Plant Equipment
D6447 Test Method for Hydroperoxide Number of Aviation Turbine Fuels by Voltammetric Analysis
D6971 Test Method for Measurement of Hindered Phenolic and Aromatic Amine Antioxidant Content in Non-zinc Turbine Oils
by Linear Sweep Voltammetry
3. Terminology
3.1 For definitions of terms used in this method, refer to Terminology D4175.
3.1 Definitions:
1
This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcommittee
D02.09.0C on Oxidation of Turbine Oils.
Current edition approved July 1, 2021July 1, 2022. Published August 2021August 2022. Originally approved in 2002. Last previous edition approved in 20132021 as
D6810 – 13.D6810 – 21. DOI: 10.1520/D6810-21.10.1520/D6810-22.
2
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.
*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
1

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D6810 − 22
3.1.1 See Terminology D4175 for a more extensive list of terms used in this test method.
3.1.2 electrolytic cell, n—an electrochemical cell in which chemical reactions are caused by applying an external potential
3
difference greater than, and opposite to, the galvanic electromotive force of the cell. IUPAC
3.1.3 linear sweep voltammetry, n—a technique applied to the monitoring of antioxidant additive content in lubricants, where the
current is detected as an applied potential is increased linearly over a period of time.
3.1.4 voltammogram, n—the plot of current versus voltage.
4. Summary of Test Method
4.1 A measured quantity of sample is dispensed into a vial containing a measured quantity of alcohol-based electrolyte solution
and containing a layer of sand. When the vial is shaken, the hindered phenol antioxidants and other solution soluble oil components
present in the sample are extracted into the solution and the remaining droplets suspended in the solution are agglomerated by the
sand. The sand/droplet suspension is allowed to settle out and the hindered phenol antioxidants dissolved in the solution are
quantified by voltammetric analysis. The results are calculated and reported as weight percent of antioxidant or as m
...