ASTM D4281-95(2005)e1

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
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Designation:D4281–95 (Reapproved 2005)
Standard Test Method for
Oil and Grease (Fluorocarbon Extractable Substances) by
Gravimetric Determination
This standard is issued under the fixed designation D4281; 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.
´ NOTE—The introduction was changed editorially in January 2006.
INTRODUCTION
In the determination of oil and grease, an absolute quantity of a specific substance is not measured.
Rather,groupsofsubstanceswithsimilarphysicalcharacteristicsaredeterminedquantitativelyonthe
basis of their common solubility in a specified fluorocarbon solvent. Oil and grease may therefore, be
said to include hydrocarbons, fatty acids, soaps, fats, waxes, oil, and any other material that is
extracted by the solvent from an acidified sample of the test. It is important that this limitation be
clearly understood. Unlike some constituents—which represent distinct chemical elements, ions,
compounds, or groups of compounds, oils and greases are defined by the method used for their
determination.
Inaccordancewith40CFR82.13,AppendixG,chlorofluorocarbon-113maynotbeusedintheUnited
States ofAmerica for the determination of oil and grease and total petroleum hydrocarbons in water.
1. Scope 1.4 These test methods measure those groups of substance
called oil and grease, whether soluble or insoluble, polar or
1.1 These test methods cover the estimation of oil and
non-polar,orbiologicalormineralinorigin,totheextentthese
grease in water and wastewater by a gravimetric determination
substances partition from the matrix into chlorofluorocarbon-
of fluorocarbon extractable substances from an acidified
113andarenotvolatilizedunderconditionsofthetest.(Seethe
sample. Also included in this estimation of oil and grease are
Introduction and Section 3 of these test methods.)
any other compounds soluble in chlorofluorocarbon-113 and
1.5 Because these test methods include an acidification step
non-volatile under the conditions of test.
prior to extraction, soluble metallic soaps are hydrolyzed and
1.2 The following two test methods are included:
recovered as fatty acids in the extraction step.
1.6 Thesetestmethodswerefullyvalidatedbycollaborative
Sections
testing in reagentType IVwater.The information on precision
Test Method A—Liquid-Liquid Extraction 10-15
Test Method B—Soxhlet Extraction 16-23
may not apply to other waters.
1.3 These test methods are applicable to natural waters and
NOTE 1—Refer to companion procedures (Test Method D3921).
domestic wastewaters. They are also suitable for most indus-
1.7 The values stated in SI units are to be regarded as the
trial wastewaters, although certain wastes may yield low
standard. The values given in parentheses are for information
results because of the presence of either excessive concentra-
only.
tions of natural greases or synthetic or modified compounds
1.8 This standard does not purport to address all of the
that are not well recovered by these test methods.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
This test method is under the jurisdiction ofASTM Committee D19 on Water priate safety and health practices and determine the applica-
andisthedirectresponsibilityofSubcommitteeD19.06onMethodsforAnalysisfor
bility of regulatory limitations prior to use. For specific hazard
Organic Substances in Water.
statements, see 12.1, 13.2, 20.1, and 20.5.
Current edition approved Dec. 1, 2005. Published January 2006. Originally
approved in 1983. Last previous edition approved in 2001 as D4281–95 (2001).
DOI: 10.1520/D4281-95R05E01.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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D4281–95 (2005)
2. Referenced Documents be varied. There may be a gradual increase in weight, presum-
ably due to the absorption of oxygen, or a gradual loss of
2.1 ASTM Standards:
weight due to volatilization.
D1129 Terminology Relating to Water
6.3 Modern industry uses a number of long-chain carbon
D1192 GuideforEquipmentforSamplingWaterandSteam
3 compounds as lubricants and emulsifiers, as well as for other
in Closed Conduits
purposes.Oftenthecompositionofthesematerialsdiffersfrom
D1193 Specification for Reagent Water
that of natural oils and greases, and may render them more
D3370 Practices for Sampling Water from Closed Conduits
soluble in water or more easily emulsified than the natural
D3856 Guide for Good Laboratory Practices in Laborato-
products. As a result, they behave as oils and greases in
ries Engaged in Sampling and Analysis of Water
treatment processes and the receiving water. The procedures
D3921 Test Method for Oil and Grease and Petroleum
described here may fail to provide complete recovery of such
Hydrocarbons in Water
,
4 5
products.
D4210 Practice for Intralaboratory Quality Control Proce-
6.4 Organic based boiler and cooling water chemicals such
dures and a Discussion on Reporting Low-Level Data
as polymeric dispersants and chelants, antifoams, filming and
D5789 Practice for Writing Quality Control Specifications
neutralizing amines, and oxygen scavengers may be recovered
for Standard Test Methods for Organic Constituents
as oil and grease when these test methods are applied to such
3. Terminology waters.
6.5 Low-boiling fractions are lost in the solvent-removal
3.1 Definitions—For definitions of terms used in these test
steps of the gravimetric procedures. Even lubrication oil
methods, refer to Terminology D1129.
fractions evaporate at a significant rate at the temperature
3.2 Definitions of Terms Specific to This Standard:
necessary for removal of the last traces of the extraction
3.2.1 oil and grease—the organic matter and other mate-
solvent. Kerosine is still more volatile and gasoline cannot be
rials extracted by the solvent from water and wastewater and
determined with any reliability by a gravimetric method.
measured by these test methods.
6.6 Suspendedsolidsmayinterferebycontributingtoemul-
4. Summary of Test Method sions.
4.1 In this test method, an acidified water sample is ex-
7. Apparatus
tracted with fluorocarbon solvent in a separatory funnel.
7.1 Drying Oven, 103°C.
4.2 In the gravimetric portion of the procedure, the fluoro-
7.2 Evaporating Flask, 250-mL capacity. A flat-bottom
carbonsolventcontainingtheextractedmaterialsisevaporated
boiling flask with standard taper fitting is recommended to
and the residue is determined gravimetrically.
facilitate solvent recycling.
7.3 Distillation Apparatus, water-cooled condenser, side
5. Significance and Use
arm, and receiver, all of appropriate standard taper fitting.
5.1 Aknowledgeofthequantityofoilandgreasepresentin
7.4 Separatory Funnels,2-LfunnelswithTFE-fluorocarbon
a waste is helpful in overcoming difficulties in wastewater
stopcocks.
treatmentplantoperation,indeterminingplantefficiencies,and
7.5 Steam Bath.
in controlling the subsequent discharge of these materials to
7.6 Desiccator.
receiving streams.
5.2 When oils and greases are discharged in wastewater or
8. Purity of Reagents
treated effluents, they often cause surface films and shoreline
8.1 Reagent grade chemicals shall be used in all tests.
deposits.
Unlessotherwiseindicated,itisintendedthatallreagentsshall
conform to the specifications of the Committee on Analytical
6. Interferences
Reagents of the American Chemical Society, where such
6.1 This test method is entirely empirical, and duplicate 6
specifications are available. Other grades may be used,
results can be obtained only by strict adherence to all details.
provided it is first ascertained that the reagent is of sufficiently
By definition, any material recovered is called oil and grease
high purity to permit its use without lessening the accuracy of
including such things as elemental sulfur and certain organic
the determination.
dyes.Inaddition,heavierresidualsofpetroleummaycontaina
8.2 Purity of Water—Unlessotherwiseindicated,references
significant portion of material insoluble in the solvent used.
to water shall be understood to mean Type IV reagent water
6.2 The rate and time of extraction in the soxhlet apparatus
conforming to Specification D1193.
must be exactly as directed because of varying solubilities of
different oils and greases. In addition, the length of time
Chanin, G., E. H. Chow, R. B.Alexander, and J. F. Powers, “ScumAnalysis:A
required for drying and cooling the extracted material cannot
New Solution to a Difficult Problem,” WWWEA-5,6-49-68.
Taras, M. J. and K. A. Blum, “Determination of Emulsifying Oil in Industrial
Wastewater,” JWPFA-40-R404-68.
2 6
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Reagent Chemicals, American Chemical Society Specifications, American
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Chemical Society, Washington, DC. For suggestions on the testing of reagents not
Standards volume information, refer to the standard’s Document Summary page on listed by the American Chemical Society, see Analar Standards for Laboratory
the ASTM website. Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
Withdrawn. The last approved version of this historical standard is referenced and National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,
on www.astm.org. MD.
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D4281–95 (2005)
9. Sampling a desiccator to room temperature. Caution—Always handle
the flask with metal tongs or weighing gloves to avoid
9.1 Collect the samples in accordance with Specification
deposition of body oils.
D1192 or Practices D3370, when applicable.
9.2 Collect grab samples only directly into the sample
NOTE 3—Run a reagent and materials blank to show that they contain
bottle. Oils and greases may be lost on any sampling equip-
nosignificantresiduewithrespecttotheprecisionofthetestmethodatthe
ment used. Do not rinse the sample bottles with the sample level measured.
prior to filling as the oils may adhere to the inside of the bottle
NOTE 4—Frequently,solventwillextractplasticizerfromplastictubing
that is used to transfer from one container to another and from shipping
and lead to high results.
container liner. Check for contamination by evaporating 180 mL of
9.3 Because a portion of the collected oils and greases may
solvent on a steam bath and weighing the residue. The solvent should
adhere to the sample bottle, analyze all of the sample collected
leavenomeasurableresiduegreaterthan0.1mg.Ifthisvalueisexceeded,
as one specimen. One-litre samples are normally specified,
distill the solvent and check the distillate for residue.
although larger or smaller samples may be taken depending on
12.2 Mark the sample bottle at the water meniscus for later
the concentration of extractables expected to be present.
determinationofsamplevolume.Pourtheacidifiedsampleinto
9.4 Leave an air space above the liquid in the sample bottle
a separatory funnel.
to facilitate handling during analysis.
9.5 Collect all samples in glass bottles with nonorganic or
12.3 Add 60 mL of fluorocarbon solvent to the sample
insoluble caps, or both. bottle, cap, and shake the bottle well. Pour the solvent into the
9.6 Acidify the sample to < pH 2 with HCl (1+1) or
separatoryfunnelandextractthesamplebyshakingvigorously
H SO (1+1) to maintain the integrity of the sample. for 2 min. Invert the separatory funnel and vent with stopcock
2 4
to relieve pressure buildup during the extraction. After the
NOTE 2—ForCleanWaterActpurposesonlyH SO shouldbeusedand
2 4
7 layers have separated, drain the solvent layer through filter
the sample should be cooled to 4°C and analyzed within 28 days.
paper held by a small funnel into the tared boiling flask. If
TEST METHOD A—LIQUID-LIQUID EXTRACTION
emulsionproblemsareanticipated,add1gNa SO tothefilter
2 4
paper cone and slowly drain the solvent through the crystals.
10. Scope
Add more Na SO if necessary.
2 4
10.1 This test method covers the estimation of oil and
NOTE 5—Solvent phase separation paper helps to keep water out.
grease from 4 to 100 mg/L in water and wastewater by a
gravimetric determination of fluorocarbon extractable sub-
12.4 If a clear solvent layer cannot be obtained due to
stances from an acidified sample.
emulsion with water, add up to 100 g of NaCl to separatory
10.2 This test method is generally applicable to samples
funnel.Shaketodissolvethesalt.Frequentlythiswillbreakthe
containing extractable substances.
emulsion.Iftheemulsioncannotbebroken,thistypeofsample
must be analyzed by the Soxhlet extraction test method.
11. Reagents and Materials
12.5 Repeat the bottle rinse and extraction with two addi-
11.1 Acetone ((CH ) CO), technical grade.
3 2
tional 60-mL portions of solvent, combining all solvent in the
11.2 Filter Paper, any high flow, low-retention grade, or
flask. Rinse the filter with 20 mL of solvent, into the flask.
optionally phase separating paper.
12.6 Proceed to 13.1.
11.3 Fluorocarbon Solvent (Chlorofluorocarbon-113 or
1,1,2-Trichloro-1,2,2-Trifluoroethane) mustbeshowntocon-
13. Procedure, Gravimetric for Test Methods A and B
tain no significant residue on evaporation. Redistill if neces-
13.1 Evaporate the solvent from the boiling flask (12.5,
sary.
20.8) on a hot water bath or steam bath. (Recovering solvent
11.4 Hydrochloric Acid (HCl), sp gr 1.19.
using a condenser system is recommended.)
11.5 Sodium Bisulfate—(NaHSO ·H O).
4 2
11.6 Sodium Chloride (NaCl). 13.2 When only a few millilitres of solvent remain (under
10 mL of solvent is not recommended), leave the flask on the
11.7 Sodium Sulfate (Na SO ), anhydrous.
2 4
11.8 Sulfuric Acid (H SO ), sp gr 1.84. steam bath and draw air through the flask using vacuum for 5
2 4
min to remove the last traces of solvent or residual water.
12. Procedure
Carefullywipetheexterioroftheflaskwithalintfreeclothand
asmallamountofacetonetoremoveanywateradheringtothe
12.1 Tare,tothenearesttenthofamilligram,aboilingflask
that has been dried at 103°C in an oven for 1 h and cooled in flask. Warning—Wear protective gloves (polyethylene or
similar solvent-resistant material) to prevent the acetone from
coming in contact with the skin. Use acetone in a fume hood.
See Title 40, Code of Federal Regulations, Part 136 (40 CFR 136), Table 2,
13.3 Place in a desiccator for 1 h, remove, and weigh
Required Containers, Preservation Techniques, and Holding Times, by the U.S.
immediately, to the nearest tenth of a milligram.
Environmental Protection Agency, available from Superintendent of Documents,
U.S. Government Print
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