ASTM D7373-12

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Designation: D7373 − 12
Standard Test Method for
Predicting Biodegradability of Lubricants Using a Bio-
1
kinetic Model
This standard is issued under the fixed designation D7373; 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* 3.1.1 aromatics fraction, n—portion of the sample desorbed
with the polar eluants. The aromatics fraction is divided into
1.1 This test method covers a procedure for predicting
nonpolar and polar based. They may contain aromatics, con-
biodegradability of lubricants using a bio-kinetic model.
densed naphthenic-aromatics, aromatic olefins, and com-
1.2 The values stated in SI units are to be regarded as
pounds containing sulfur, nitrogen, and oxygen atoms.
standard. The values given in parentheses are for information
3.1.2 bio-kinetic model, n—model that can predict the bio-
only.
degradability of a lubricant.
1.3 This standard does not purport to address all of the
3.1.3 biodegradability, n—ability of a substance to be bro-
safety concerns, if any, associated with its use. It is the
ken down into simpler substances by bacteria.
responsibility of the user of this standard to establish appro-
3.1.4 effective composition to biodegradation (ECB),
priate safety and health practices and determine the applica-
n—component of material that can be biodegradable by bacte-
bility of regulatory limitations prior to use.
ria.
3.1.4.1 Discussion—The term ECB is a part of bio-kinetic
2. Referenced Documents
model is sum of non-aromatic components in a lubricant.
2
2.1 ASTM Standards:
3.1.5 nonaromatics fraction, n—portion of the sample
D2549 Test Method for Separation of Representative Aro-
eluted with n-pentane. The nonaromatics fraction is a mixture
matics and Nonaromatics Fractions of High-Boiling Oils
of paraffinic and naphthenic hydrocarbons if sample is a
by Elution Chromatography
straight-run material. If the sample is a cracked stock, the
D5864 Test Method for Determining Aerobic Aquatic Bio-
nonaromatics fraction will also contain aliphatic and cyclic
degradation of Lubricants or Their Components
olefins.
D6300 Practice for Determination of Precision and Bias
Data for Use in Test Methods for Petroleum Products and
4. Summary of Test Method
Lubricants
4.1 A weighed amount of sample is charged to the top of a
D6731 Test Method for Determining the Aerobic, Aquatic
glass chromatographic column packed with activated bauxite
Biodegradability of Lubricants or Lubricant Components
and silica gel.To elute the nonaromatics, n-pentane is added to
in a Closed Respirometer
thecolumn.Whenallofthenonaromaticsareeluted,non-polar
aromatics fraction is eluted by additions of an equal mixture of
3. Terminology
toluene and n-pentane.The ester fraction is eluted by additions
3.1 Definitions:
of diethyl ether. Then, the polar-aromatics is eluted by chloro-
form and ethyl alcohol.
1 4.2 The solvents are completely removed by evaporation,
This test method is under the jurisdiction of ASTM Committee D02 on
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of and the residues are weighed and calculated as the
Subcommittee D02.12 on Environmental Standards for Lubricants.
nonaromatics, nonpolar aromatics, ester fractions, and polar
Current edition approved June 1, 2012. Published October 2012. Originally
aromatics of the sample.
ε1
approved in 2007. Last previous edition approved in 2007 as D7373–07 . DOI:
10.1520/D7373-12.
4.3 ECB is calculated based on the amount of nonaromatics
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
and ester fractions with their material ECB coefficients. Then,
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
the biodegradability of a lubricant is calculated using the
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. bio-kinetic model.
*A Summary of Changes section appears at the end of this standard
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D7373 − 12
FIG. 1 Test Apparatus
5. Significance and Use used, provided it is first ascertained that the reagent is of
sufficiently high purity to permit its use without lessening the
5.1 This procedure is able to predict the biodegradability of
3 accuracy of the determination.
lubricants within a day without dealing with microorganisms.
Excellent correlation is established between the test results and 7.2 Bauxite, 20- to 60-mesh—Before use, activate the baux-
the conventional
...