1、Designation: D 3921 96 (Reapproved 2003)e1Standard Test Method forOil and Grease and Petroleum Hydrocarbons in Water1This standard is issued under the fixed designation D 3921; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.e1NOTEEditorial changes were made througho
3、ut in January 2003.1. Scope1.1 This test method covers the determination offluorocarbon-extractable substances as an estimation of thecombined oil and grease and the petroleum hydrocarboncontents of a sample of water or waste water in the range from0.5 to 100 mg/L. It is the users responsibility to
4、assume thevalidity of the standard for untested types of water.1.2 This test method defines oil and grease in water andwaste water as that matter which is extractable in the testmethod and measured by infrared absorption. Similarly, thistest method defines petroleum hydrocarbons in water and wastewa
5、ter as that oil and grease which is not adsorbed by silica gelin the test method and that is measured by infrared absorption.1.3 Low-boiling organic materials are lost by evaporationduring the manipulative transfers. However, these evaporativelosses are generally much lower than those experienced wi
6、thgravimetric procedures that require solvent evaporation beforethe residue is weighed.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices
7、and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:D 1129 Terminology Relating to Water2D 1193 Specification for Reagent Water2D 2777 Practice for Determination of Precision and Bias ofApplicable Methods of Committee D19 on Water2D 3325
8、Practice for Preservation of Waterborne OilSamples3D 3370 Practices for Sampling Water from Closed Con-duits2D 3856 Guide for Good Laboratory Practices in Laborato-ries Engaged in Sampling and Analysis of Water2D 5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for W
9、ater Analysis3E 168 Practices for General Techniques of Infrared Quan-titative Analysis43. Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, refer to Terminology D 1129 and Practices E 168.3.2 Definitions of Terms Specific to This Standard:3.2.1 oil and greasethe organic ma
10、tter extracted fromwater or waste water and measured by this test method.3.2.2 petroleum hydrocarbonsthe oil and grease remain-ing in solution after contact with silica gel and measured bythis test method.4. Summary of Test Method4.1 The acidified sample of water or waste water is ex-tracted seriall
11、y with three 30-mLvolumes of 1, 1, 2-trichloro-1,2, 2-trifluoroethane (referred to in this test method as sol-vent).5The extract is diluted to 100 mL and a portion isexamined by infrared spectroscopy6to measure the amount ofoil and grease removed from the original sample. A majorportion of the remai
12、ning extract is contacted with silica gel toremove polar substances, thereby providing a solution ofpetroleum hydrocarbons. This treated extract is then similarlyexamined by infrared spectroscopy.5. Significance and Use5.1 The presence of oil and grease in domestic and indus-trial waste water is of
13、concern to the public because of itsdeleterious aesthetic effect and its impact on aquatic life.Regulations and standards have been established that requiremonitoring of oil and grease in water and waste water. This test1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is
14、 the direct responsibility of Subcommittee D19.06 on Methods forAnalysis forOrganic Substances in Water.Current edition approved Jan. 10, 2003. Published January 2003. Originallyapproved in 1980. Last previous edition approved in 1996 as D 3921 96.2Annual Book of ASTM Standards, Vol 11.01.3Annual Bo
15、ok of ASTM Standards, Vol 11.02.4Annual Book of ASTM Standards, Vol 03.06.5Gruenfeld, M., “Extraction of Dispersed Oils from Water for QuantitativeAnalysis by Infrared Spectrophotometry,” Environmental Science and Technology,Vol 7, 1973, pp. 636639.6Consult the manufacturers operation manual for the
16、 specific instructionsrelated to the infrared spectrometer or analyzer to be used.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.method provides an analytical procedure to measure oil andgrease in water and waste water.6. Interferen
17、ces6.1 Since the constituents oil and grease and petroleumhydrocarbons are defined as the results of the test procedure,interferences are precluded by definition. Interpretation of testresults on the basis of chemical structure, pollution potential, ortreatability should be approached with caution,
18、however, be-cause of the diversity of substances measured by this proce-dure.6.2 Organic solvents and certain other organic compoundsnot considered as oil and grease on the basis of chemicalstructure may be extracted and measured as oil and grease. Ofthose measured, certain ones may be adsorbed by s
19、ilica gelwhile others may not. Those which are not adsorbed aremeasured as petroleum hydrocarbons.7. Apparatus7.1 Cell(s), quartz, 10-mm path length, two required fordouble-beam operation, one required for single-beam opera-tion, or built-in cell for nondispersive infrared analyzer opera-tion.7.2 Fi
20、lter Paper, ashless, quantitative, general-purpose,11-cm or equivalent.7.3 Glass Bottle, approximately 1000-mL, with screw caphaving a TFE-fluorocarbon liner.7.4 Graduated Cylinder, 1000-mL.7.5 Infrared Spectrometer, double-beam dispersive, single-beam dispersive, Fourier transform, or nondispersive
21、 infraredanalyzer.7.6 Magnetic Stirrer, with small TFE-fluorocarbon stirringbar.7.7 Separatory Funnel, 2000-mL, with TFE-fluorocarbonstopcock (one for each sample analyzed during any one periodof time).7.8 Volumetric Flask, 100-mL (minimum of six required forcalibration plus one for each sample anal
22、yzed during any oneperiod of time).8. Reagents8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specification of the Committeeon Analytical Reagents of the American Chemical Society,7where such sp
23、ecifications are available. Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.8.2 Purity of Water Unless otherwise indicated, refer-ences to water (not sample water) shall be u
24、nderstood to meanreagent water conforming to Specification D 1193, Type II.8.3 Calibration Oil and Grease, similar in composition tooil and grease determined by this test method for possible useas calibration material.8.4 Cetane (n-Hexadecane), 99 % minimum purity, forpossible use in calibration mix
25、ture.8.5 Isooctane (2,2,4-Trimethylpentane), 99 % minimum pu-rity, for possible use in calibration mixture.8.6 Silica Gel8, 100 to 200 mesh, which has been deacti-vated with 2 % water.8.7 Sodium Bisulfate (NaHSO4), monohydrate.8.8 Sodium Sulfate (Na2SO4), anhydrous, granular.8.9 Solvent 1, 1, 2-tric
26、hloro-1, 2, 2- trifluoroethane.9NOTE 1Frequently, this solvent will extract plasticizer from the linerof its shipping container. Check for such contamination by evaporating100 mL of solvent in a steam bath and weighing its residue. If this valueexceeds 0.1 mg, purify the solvent by distillation and
27、check the overheadmaterial for residue. Store the purified solvent in clean, glass bottleshaving TFE-Fluorocarbon cap liners. Purification of this solvent as amatter of course is highly desirable.8.10 Sulfuric Acid (1 + 1)Slowly and carefully add 1volume of sulfuric acid (H2SO4, sp gr 1.84) to 1 vol
28、ume ofwater, stirring and cooling the solution during the addition.9. Sampling9.1 Collect the sample in accordance with the principlesdescribed in Practices D 3370, using a glass bottle equippedwith a screw cap having a TFE-fluorocarbon liner.9.2 A sample of about 750 mL is required for this test. U
29、sethe entire sample since no portion should be removed for othertests.9.3 Preserve the sample with a sufficient quantity of eithersulfuric acid (see 8.10) or sodium bisulfate (see 8.7) to attain apH of 2 or lower. The amount of reagent required will bedependent upon the pH of the sample at the time
30、of collectionand upon its buffer capacity.10. CalibrationNOTE 2Achoice of two calibration species is available to the analyst.The preferred material is a sample of the same oil and grease that is knownto be present in the sample of water or waste water awaiting analysis. Theother material is a mixtu
31、re of isooctane and cetane. This latter blend is tobe used when the same (as described) material is not available.10.1 If the blend of isooctane and cetane is to be used forcalibration, prepare a calibration mixture by pipetting 15 mLofisooctane and 15 mL of cetane into a glass-stoppered bottle.Mix
32、the contents well and maintain the integrity of the mixtureby keeping the container tightly sealed except when a portionis withdrawn for blending.10.2 Calibration Solution Blend APlace about 20 mL ofsolvent into a 100-mL volumetric flask, stopper, and weigh. Tothis flask quickly add about 1 mL of ei
33、ther the calibration oiland grease or the calibration mixture of isooctane and cetane.Obtain its exact weight by difference. Fill to the mark with7Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlist
34、ed by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,MD.8Silica Gel, Davison Chemical Grade 923 has been found to be satisfact
35、ory forthis purpose. Other available types from the same or different suppliers may besuitable.9This solvent is available also as Freon 113, Freon TF, Freon PCA, Genetron113, Genesolve D, and as other names.D 3921 96 (2003)e12solvent and mix the liquid well by shaking the flask. Calculatethe exact c
36、oncentration of the calibrating material in solution interms of mg/100 mL. If the calibration oil and grease is used,proceed to 10.3. If the calibration mixture is used, multiply thiscalculated concentration (about 730 mg/100 mL) by 1.4 (referto Note 3). This new concentration value (about 1022 mg/1
37、00mL) is to be used for Blend A throughout the remainder of thistest method.NOTE 3Dating back to at least 1951,10for many years a mixture ofisooctane, cetane, and benzene was accepted as a standard for calibration.Concern regarding the hazards of exposure to benzene, which acts hereonly as a diluent
38、 having no contribution at 2930 cm1(3.41 m), hasprompted elimination of this chemical as a component for calibration. Tomaintain relevance between current and future analytical data with thoseof the past, it is necessary to compensate for differences in concentrationand in density between the former
39、 and the present calibration standards.The factor of 1.4 accomplishes this because the weight ratio of combinedisooctane plus cetane in the new two-way mixture to that in the olderthree-way mixture is 1.000 to 0.714, or 1.40. Henceforth, all concentra-tions involving the calibration mixture will be
40、based upon the convertedvalue obtained in 10.2.10.3 Calibration Solution Blend BDilute 4 mLof BlendAwith solvent in a 100-mL volumetric flask (about 41 mg/100mL).10.4 Calibration Solution Blend CDilute 3 mLof BlendAwith solvent in a 100-mL volumetric flask (about 31 mg/100mL).10.5 Calibration Soluti
41、on Blend DDilute 50 mL of BlendB with solvent in a 100-mL volumetric flask (about 20 mg/100mL).10.6 Calibration Solution Blend EDilute 30 mL of BlendC with solvent in a 100-mL volumetric flask (about 9 mg/100mL).10.7 Calibration Solution Blend FDilute 10 mL of BlendE with solvent in a 100-mL volumet
42、ric flask (about 0.9 mg/100mL).NOTE 4During the calibration events which follow, the cell used forthe blends must be thoroughly cleaned with fresh solvent and then driedprior to the addition of a new blend. Take care to avoid insertion of the cellstopper so tightly that the cell could burst from exp
43、ansion of its contentsas it resides in the light beam. It is desirable to flush the cell compartmentof the spectrometer with nitrogen or dry air to prevent chemical reactionof solvent fumes with components of the instrument. For double-beamoperation, either block the light beam from the reference ce
44、ll containingsolvent or remove the reference cell from the instrument during theintervals between scans in order to protect the solvent from unnecessarywarming. However, place the reference cell in the reference beam duringall scans. For single-beam operation, use the same cell throughout thecalibra
45、tion procedure. Rely upon sole recommendations of the manufac-turer for single-beam and nondispersive infrared analyzers since variationsin design make it impractical to offer instructions for their use with thismethod. Also, in relation to nondispersive infrared operation, reference toscanning or r
46、unning, or both, should be interpreted to mean obtaining areading or a plot of the 2930-cm1(3.41-m) band.10.8 Fill the reference cell (for double-beam operation) andthe sample cell with solvent and scan from 3200 cm1(3.13m) to 2700 cm1(3.70 m). A nearly horizontal, straight lineshould be obtained. I
47、f it is not, check cells for cleanliness,matching, etc. Drain and clean the sample cell. Obtain spectraldata for the solvent at this time for single-beam and nondis-persive infrared instruments, also. After running, drain, andclean the sample cell.10.9 Fill the sample cell with Blend B. Scan as in 1
48、0.8;drain, and clean the sample cell.10.10 Fill the sample cell with Blend C. Scan as in 10.8;drain, and clean the sample cell.10.11 Fill the sample cell with Blend D. Scan as in 10.8;drain, and clean the sample cell.10.12 Fill the sample cell with Blend E. Scan as in 10.8;drain, and clean the sampl
49、e cell.10.13 Fill the sample cell with Blend F. Scan as in 10.8;drain, and clean the sample cell.10.14 For each double-beam spectrum obtained in 10.9through 10.13, draw a baseline similar to that found in Fig. 1.Obtain the net absorbance for the peak that occurs near 2930cm1(3.41 m). Obtain net values for single-beam andnondispersive infrared runs as recommended.NOTE 5For infrared instruments having computer capability, datamay be obtained automatically or as described in 10.14. However, all datamust be obtained consistently by one means or the other, no
