1、Designation: D2172/D2172M 11Standard Test Methods forQuantitative Extraction of Bitumen From Bituminous PavingMixtures1This standard is issued under the fixed designation D2172/D2172M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision
2、, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 These test methods cove
3、r the quantitative determinationof bitumen in hot-mixed paving mixtures and pavementsamples. Aggregate extracted from a paving mixture may beused for sieve analysis using Test Method D5444.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The valu
4、es stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.2.1 Measurements of volume and mass are only given inSI units because they are the only units ty
5、pically used inpractice when performing this test method.1.3 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 and determine the applica-bili
6、ty of regulatory limitations prior to use. Specific hazards aregiven in Section 7.NOTE 1The results obtained by these test methods may be affected bythe age of the material tested, with older samples tending to yield slightlylower bitumen content. Best quantitative results are obtained when the test
7、is made on mixtures and pavements shortly after their preparation. It isdifficult to remove all the asphalt when some aggregates are used andsome chlorides may remain within the mineral matter affecting themeasured asphalt content.2. Referenced Documents2.1 ASTM Standards:2C128 Test Method for Densi
8、ty, Relative Density (SpecificGravity), and Absorption of Fine AggregateC670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsD70 Test Method for Density of Semi-Solid BituminousMaterials (Pycnometer Method)D604 Specification for Diatomaceous Silica Pigm
9、ent3D979 Practice for Sampling Bituminous Paving MixturesD1461 Test Method for Moisture or Volatile Distillates inBituminous Paving MixturesD1856 Test Method for Recovery of Asphalt From Solutionby Abson MethodD2111 Test Methods for Specific Gravity and Density ofHalogenated Organic Solvents and The
10、ir AdmixturesD3666 Specification for Minimum Requirements for Agen-cies Testing and Inspecting Road and Paving MaterialsD5444 Test Method for Mechanical Size Analysis of Ex-tracted AggregateD6368 Specification for Vapor-Degreasing Solvents Basedon normal-Propyl Bromide and Technical Grade normal-Pro
11、pyl Bromide2.2 Federal Specifications:O-T-634 (latest) normal Propyl Bromide, Technical43. Summary of Test Methods3.1 The paving mixture is extracted with trichloroethylene,normal Propyl Bromide, or methylene chloride using theextraction equipment applicable to the particular method. Thebitumen cont
12、ent is calculated by difference from the mass ofthe extracted aggregate, moisture content, and mineral matterin the extract. The bitumen content is expressed as masspercent of moisture-free mixtures.4. Significance and Use4.1 All of these test methods can be used for quantitativedeterminations of bi
13、tumen in hot-mixed paving mixtures andpavement samples for specification acceptance, service evalu-ation, control, and research. Each method prescribes thesolvent or solvents and any other reagents that can be used in1These test methods are under the jurisdiction of ASTM Committee D04 onRoad and Pav
14、ing Materials and are the direct responsibilities of SubcommitteeD04.25 on Analysis of Bituminous Mixtures.Current edition approved Feb. 1, 2011. Published March 2011. Originallyapproved in 1963. Last previous edition approved in 2005 as D2172 05. DOI:10.1520/D2172-11.2For referenced ASTM standards,
15、 visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.o
16、rg.4Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.the test method. Test Method D1856 requires that Me
17、thod A beused when asphalt is recovered from solution.NOTE 2The quality of the results produced by this standard aredependent on the competence of the personnel performing the procedureand the capability, calibration, and maintenance of the equipment used.Agencies that meet the criteria of Standard
18、Practice D3666 are generallyconsidered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance withPractice D3666 alone does not completely assure reliable results. Reliableresults depend on many factors; following the suggestions of P
19、racticeD3666 or some similar acceptable guideline provides a means ofevaluating and controlling some of those factors.5. Apparatus5.1 Oven, capable of maintaining the temperature at 110 65C 230 6 10F.5.2 Pan, flat, at least 300 mm 12 in. long, 200 mm 8 in.wide, and 25 mm 1 in. deep.5.3 Balance, or b
20、alances having an accuracy of at least0.01 % of the sample mass.5.4 Hot Plate, electric, 700-W continuous or low, medium,and high settings.5.5 Small-Mouth Graduate, 1000 or 2000-mL capacity.Optional small-mouth graduate, 100-mL capacity.5.6 Ignition Dish, 125 mL capacity.5.7 Desiccator.5.8 Analytica
21、l Balance.6. Reagents6.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee onAnalytical Reagents of theAmerican Chemical Society,5where such specifications are availab
22、le. 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.6.2 Ammonium Carbonate SolutionSaturated solution ofreagent grade ammonium carbonate (NH4)2CO3.6.3 Methylene Chloride, tec
23、hnical grade. CautionseeSection 7.6.4 normal-Propyl Bromide (nPB), conforming to Specifi-cation D6368. Cautionsee Section 7.6.5 Trichloroethylene, technical grade, Type 1, FederalSpecification O-T-634, latest revision. Cautionsee Section7.7. Hazards7.1 CautionThe solvents listed in Section 6 should
24、beused only under a hood or with an effective surface exhaustsystem in a well-ventilated area, since they are toxic to variousdegrees. Consult the current Threshold Limit ConcentrationCommittee of the American Conference of GovernmentalIndustrial Hygienists6for the current threshold limit values.8.
25、Sampling8.1 Obtain samples in accordance with Practice D979.8.2 Preparation of Test Specimens:8.2.1 If the mixture is not sufficiently soft to separate with aspatula or trowel, place it in a large, flat pan and warm to 1106 5C 230 6 10F only until it can be handled or mixed.Split or quarter the mate
26、rial until the mass of material requiredfor test is obtained.8.2.2 The size of the test sample shall be governed by thenominal maximum aggregate size of the mixture and shallconform to the mass requirement shown in Table 1 (Note 3):NOTE 3When the mass of the test specimen exceeds the capacity ofthe
27、equipment used (for a particular method), the test specimen may bedivided into suitable increments, tested, and the results appropriatelycombined for calculation of bitumen content (Section 12).8.2.3 In addition, a test specimen is required for the deter-mination of moisture (Section 9) in the mixtu
28、res. Take this testspecimen from the remaining sample of the mixture immedi-ately after obtaining the extraction test specimen.NOTE 4If recovery of bitumen from the solution obtained from theextraction test is not required, the entire test specimen may be dried toconstant mass in an oven at a temper
29、ature of 110 6 5C 230 6 10Fprior to extraction instead of determining the moisture content (Section 9).9. Moisture Content9.1 Determine the moisture content of the mixture (see8.2.2) in accordance using the procedure described in TestMethod D1461.9.2 Calculate the mass of water, W2,(12.1) in the ext
30、ractiontest portion by multiplying mass percent water (9.1)bythemass of the extraction test portion, W1,(12.1).TEST METHOD A10. Apparatus10.1 In addition to the apparatus listed in Section 5, thefollowing apparatus is required for Test Method A:10.1.1 Extraction Apparatus, consisting of a bowl appro
31、xi-mating that shown in Fig. 1 and an apparatus in which the bowlmay be revolved at controlled variable speeds up to 3600r/min. The speed may be controlled manually or with a preset5Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions
32、 on the testing of reagents notlisted 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. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.6Available from American Conference
33、of Governmental Industrial Hygienists,1330 Kemper Meadow Drive, Cincinnati, OH 45240, (513) 7422020, (www.acgi-h.org).TABLE 1 Size of SampleNominal MaximumAggregate Size Standard,mmSieve SizeMinimum Mass of Sample,kg4.75 (No. 4) 0.59.538 in. 112.512 in. 1.519.034 in. 225.0 1 in. 337.5 112 in. 4D2172
34、/D2172M 112speed control. The apparatus should be provided with acontainer for catching the solvent thrown from the bowl and adrain for removing the solvent. The apparatus preferably shallbe provided with explosion-proof features and installed in ahood or an effective surface exhaust system to provi
35、de venti-lation.NOTE 5Similar apparatus of larger size may be used.10.1.2 Filter Rings, felt or paper, to fit the rim of the bowl.10.1.3 Low-ash paper filter rings may be used in place of thefelt filter ring (10.1.2). Such filter rings shall consist of low ashfilter paper stock approximately 1.3 mm
36、0.05 in. thick. Theash content of the paper shall not exceed 0.2 % (approximately0.034 g per ring).11. Procedure11.1 Determine the moisture content of the material inaccordance with Section 9.FIG. 1 Extraction Unit Bowl (Test Method A)D2172/D2172M 11311.2 Place a 650 to 2500-g test portion into a bo
37、wl. SeeAnnex A1 for alternative procedures to those prescribed hereinand in 11.5.11.3 Cover the test portion in the bowl with trichloroethyl-ene, normal Propyl Bromide, or methylene chloride and allowsufficient time for the solvent to disintegrate the test portion(not over 1 h). Place the bowl conta
38、ining the test portion andthe solvent in the extraction apparatus. Dry and determine themass of the filter ring and fit it around the edge of the bowl.Clamp the cover on the bowl tightly and place a beaker underthe drain to collect the extract.11.4 Start the centrifuge revolving slowly and gradually
39、increase the speed to a maximum of 3600 r/min or until solventceases to flow from the drain. Allow the machine to stop, add200 mL of trichloroethylene, normal Propyl Bromide, ormethylene chloride and repeat the procedure. Use sufficient200-mL solvent additions (not less than three) so that theextrac
40、t is not darker than a light straw color. Collect the extractand the washings in a suitable graduate.11.5 Remove the filter ring from the bowl and dry in air. Iffelt filter rings are used, brush off mineral matter adhering tothe surface of the ring and add to the extracted aggregate. Drythe ring to
41、constant mass in an oven at 110 6 5C 230 610F. Carefully remove all the contents of the bowl into ametal pan and dry on a steam bath and then, dry to constantmass in an oven or on a hot plate at 110 6 5C 230 6 10F.If trichloroethylene or normal Propyl Bromide is used as theextraction solvent, the pr
42、eliminary drying on a steam bath maybe omitted. The mass of the extracted aggregate, W3, is equalto the mass of the aggregate in the pan plus the increase in massof the filter rings.11.5.1 Use the following alternative procedure when low-ash filter rings are used: Place the aggregate and filter ring
43、s ina clean metal pan. Dry as specified above. Carefully fold thedried filter ring and stand it on the aggregate. Burn the filterring by igniting with a bunsen burner or match. Determine themass of the extracted aggregate in the pan, W3.NOTE 6Since dry aggregate absorbs moisture when exposed to airc
44、ontaining moisture, determine the mass of the extracted aggregateimmediately after cooling to a suitable temperature.11.6 Determine the amount of mineral matter in the extractby any of the following test methods:11.6.1 Ashing Method:11.6.1.1 Record the volume of the total extract in thegraduate (11.
45、4). Determine the mass of an ignition dish.Agitatethe extract thoroughly and immediately measure approximately100 mL into the ignition dish. Evaporate to dryness on a steambath or hot plate, except use a steam bath when the solvent isbenzene. Ash residue at a dull red heat 500 to 600C 930 to1110F, c
46、ool, and add 5 mL of saturated ammonium carbonatesolution per gram of ash. Digest at room temperature for 1 h.Dry in an oven at 100C to constant mass, cool in a desiccator,and determine the mass.11.6.1.2 Calculate the mass of mineral matter in the totalvolume of extract, W4, as follows:W45 GV1/V12 V
47、2!# (1)where:G = ash in aliquot, g,V1= total volume, mL, andV2= volume after removing aliquot, mL.11.6.2 Centrifuge Method:11.6.2.1 For this test method use any suitable high-speed(3000 g or higher) centrifuge of the continuous-flow type.11.6.2.2 Determine the mass of a clean empty centrifugecup (or
48、 bowl) to 0.01 6 0.005 g and place in the centrifuge.Position a container at the appropriate spout to catch theeffluent from the centrifuging operation. Transfer all of theextract (from Test Methods A, B, C, D, or E as appropriate) toan appropriate (feed) container suitably equipped with a feedcontr
49、ol (valve or clamp, etc.). To ensure quantitative transfer ofthe extract to the feed container, the receptacle containing theextract should be washed several times with small amounts ofclean solvent and the washings added to the feed container.Start the centrifuge and allow to reach a constant operationalspeed (for example, 9000 r/min for the SMM type and20 000 + r/min for the Sharples type). Open the feed line andfeed the extract into the centrifuge at a rate of 100 to 150mL/min.After all the extract has passed through the cen
