ASTM D7923-16

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D7923 − 16
Standard Test Method for
Water in Ethanol and Hydrocarbon Blends by Karl Fischer
1
Titration
This standard is issued under the fixed designation D7923; 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 D1193 Specification for Reagent Water
D4057 Practice for Manual Sampling of Petroleum and
1.1 This test method covers the determination of water from
Petroleum Products
0.05 % to 5.0 % by mass in blends of ethanol, hydrocarbon,
D4175 Terminology Relating to Petroleum Products, Liquid
and corresponding blends. It is intended for measuring water
Fuels, and Lubricants
contentofgasolineorotherhydrocarbonblendstock,denatured
D4177 Practice for Automatic Sampling of Petroleum and
fuel ethanol as cited in Specification D4806, and ethanol fuel
Petroleum Products
blends such as those cited in Specification D5798 and Practice
D4806 Specification for Denatured Fuel Ethanol for Blend-
D7794. This test method is not applicable to samples that are
ing with Gasolines for Use as Automotive Spark-Ignition
phase separated.
Engine Fuel
1.1.1 Procedure A—For measurement of water up to 2 % by
D5798 Specification for Ethanol Fuel Blends for Flexible-
mass in ethanol and hydrocarbon blends using coulometric
Fuel Automotive Spark-Ignition Engines
Karl Fischer titration. This is the referee method for samples
D6299 Practice for Applying Statistical Quality Assurance
containing up to 2 % ethanol.
and Control Charting Techniques to Evaluate Analytical
1.1.2 Procedure B—For measurement of water up to 5.4 %
Measurement System Performance
by mass in ethanol and hydrocarbon blends using volumetric
D6708 Practice for StatisticalAssessment and Improvement
Karl Fischer titration.
of Expected Agreement Between Two Test Methods that
1.2 This method measures mass percent water and allows
Purport to Measure the Same Property of a Material
for the alternative reporting of volume percent. This test
D7794 Practice for Blending Mid-Level Ethanol Fuel
method recommends the use of pyridine-free reagents.
BlendsforFlexible-FuelVehicleswithAutomotiveSpark-
1.3 The values stated in SI units are to be regarded as Ignition Engines
standard. No other units of measurement are included in this E203 Test Method for Water Using Volumetric Karl Fischer
Titration
standard.
E1064 Test Method for Water in Organic Liquids by Coulo-
1.4 This standard does not purport to address all of the
metric Karl Fischer Titration
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3. Terminology
priate safety and health practices and determine the applica-
3.1 For general terminology, refer to Terminology D4175.
bility of regulatory limitations prior to use. Specific precau-
tionary statements are given in Section 8. 3.2 Definitions:
3.2.1 denatured fuel ethanol, n—fuel ethanol made unfit for
2. Referenced Documents
beverage use by the addition of denaturants under formula(s)
2
approved by the applicable regulatory agency to prevent the
2.1 ASTM Standards:
imposition of beverage alcohol tax. D4806
D1152 Specification for Methanol (Methyl Alcohol)
3.2.2 hydrocarbon, n—a compound composed solely of
hydrogen and carbon. D5798
1
3.2.2.1 Discussion—The hydrocarbon mixtures used in
This test method is under the jurisdiction of ASTM Committee D02 on
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of
ethanol fuel blends will be unleaded gasoline, gasoline blend-
Subcommittee D02.06 on Analysis of Liquid Fuels and Lubricants.
stock for oxygenate blending (BOB), natural gasoline, or other
Current edition approved July 1, 2016. Published August 2016. DOI: 10.1520/
hydrocarbons in the gasoline boiling range. The hydrocarbon
D7923-16.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or blend components will also contain trace quantities of other
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
elements.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. 3.3 Definitions of Terms Specific to This Standard:
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D7923 − 16
3.3.1 coulometric titration, n—in reference to Karl Fischer vessel that reacts stoichiometrically with the water present in
titration methods, a process of measuring the water content of the sample solution. The titrant solution is standardized to
a sample using an electrolytic proces
...