ASTM D5404 D5404M-2011 Standard Practice for Recovery of Asphalt from Solution Using the Rotary Evaporator《用旋转蒸气装置从溶液中回收沥青的标准操作规程》.pdf

1、Designation: D5404/D5404M 11Standard Practice forRecovery of Asphalt from Solution Using the RotaryEvaporator1This standard is issued under the fixed designation D5404/D5404M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the yea

2、r 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.1. Scope1.1 This practice is intended to recover asphalt from asolvent using the rotary evaporator to ensure that changes int

3、he asphalt properties during the recovery process are mini-mized.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combin

4、ingvalues from the two systems may result in non-conformancewith the standard.1.2.1 Residual pressure measurements are shown in both theSI unit of kPa and the commonly used non-standard equivalentunit of “mm of Hg”.1.2.2 Measurements of volume and mass are only given inSI units because they are the

5、only units typically used inpractice when performing this standard practice.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 determi

6、ne the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D92 Test Method for Flash and Fire Points by ClevelandOpen Cup TesterD1856 Test Method for Recovery of Asphalt From Solutionby Abson MethodD2939 Test Methods for Emulsified Bitumens Used asProtect

7、ive CoatingsD3666 Specification for Minimum Requirements for Agen-cies Testing and Inspecting Road and Paving MaterialsD6368 Specification for Vapor-Degreasing Solvents Basedon normal-Propyl Bromide and Technical Grade normal-Propyl Bromide3. Summary of Practice3.1 The solution of solvent and asphal

8、t from a prior extrac-tion is distilled by partially immersing the rotating distillationflask of the rotary evaporator in a heated oil bath while thesolution is subjected to a partial vacuum and a flow of nitrogengas or carbon dioxide gas. The recovered asphalt can then besubjected to testing as req

9、uired.4. Significance and Use4.1 In order to determine the characteristics of the asphalt inan asphalt paving mixture, it is necessary to extract the asphaltfrom the aggregate by means of a suitable solvent and then torecover the asphalt from the solvent without significantlychanging the asphalts pr

10、operties. The asphalt recovered fromthe solvent by this practice can be tested using the samemethods as for the original asphalt cement, and comparisonsbetween the properties of the original and recovered asphaltcan be made.NOTE 1The quality of the results produced by this standard aredependent on t

11、he competence of the personnel performing the procedureand the capability, calibration, and maintenance of the equipment used.Agencies that meet the criteria of Standard Practice D3666 are generallyconsidered capable of competent and objective testing/sampling/inspection/etc. Users of this standard

12、are cautioned that compliance withPractice D3666 alone does not completely assure reliable results. Reliableresults depend on many factors; following the suggestions of PracticeD3666 or some similar acceptable guideline provides a means ofevaluating and controlling some of those factors.5. Apparatus

13、5.1 Rotary Evaporator (see Fig. 1), equipped with a distil-lation flask, a variable speed motor capable of rotating thedistillation flask at a rate of at least 50 rpm, condenser, solventrecovery flask, and heated oil bath. The angle of the distillationflask from the horizontal to the bath is set at

14、approximately 15.1This practice is under the jurisdiction of ASTM Committee D04 on Road andPaving Materials and is the direct responsibility of Subcommittee D04.25 onAnalysis of Bituminous Mixtures.Current edition approved Jan. 1, 2011. Published March 2011. Originallyapproved in 1997. Last previous

15、 edition approved in 2003 as D5404 03. DOI:10.1520/D5404_D5404M-11.2For referenced ASTM standards, 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 we

16、bsite.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.The distillation flask (Note 2), when fully immersed, should beat a depth of approximately 40 mm 1.5 in.NOTE 2A flask having a 2000 mL capacity is recommended.5.2 Manometer or Vac

17、uum Gage, suitable for measuring thespecified vacuum.5.3 Gas Flowmeter, capable of indicating a gas flow of up to1000 mL/min.5.4 Sample Container, having adequate volume to hold thesample and added solvent.5.5 Vacuum System, capable of maintaining a vacuum towithin 60.7 kPa 65 mm of Hg of the desire

18、d level up to andincluding 80 kPa 600 mm of Hg.6. Reagents and Materials6.1 Nitrogen Gas or Carbon Dioxide GasA pressurizedtank with pressure-reducing valve, or other convenient source.NOTE 3Different flow rates may be required depending on whethernitrogen gas or carbon dioxide gas is used.6.2 OilTh

19、e oil for the heated oil bath should be USPWhite Oil or Silicone Fluid SWS-101 with flash point above215C 420F or an equivalent. The flash point is determinedin accordance with Test Method D92.6.3 Solvents:6.3.1 Trichloroethylene and Methylene ChlorideThe sol-vent for extracting the asphalt from mix

20、tures should be reagentgrade trichloroethylene or methylene chloride. A technicalgrade of trichloroethylene may be used, but it is recommendedthat for each new supply of solvent, a blank should be run onan asphalt with known properties.6.3.2 Normal Propyl Bromides (nPB)The solvent forextracting the

21、asphalt from the mixtures should conform toSpecification D6368. Because there may be some interactionsdue to differences in nPB products, it is recommended that fora new supply of solvent, a blank should be run on an asphaltwith known properties.7. Precautions7.1 CautionThe solvents listed in 6.3 sh

22、ould be used onlyunder a hood or with an effective surface exhaust system in awell ventilated area, since they are toxic to various degrees.Consult the current Threshold Limit Concentration Committeeof the American Conference of Governmental Industrial Hy-gienists3for the current threshold limit val

23、ues.7.2 These solvents in the presence of heat and moisture maybe hydrolyzed to form acids that are extremely corrosive tocertain metals, particularly when subject to contact overlengthy periods of time. Proper precautions should be taken tonot allow these solvents to remain in small quantities in t

24、heeffluent tanks of aluminum vacuum extractors.7.3 Exposure of these solvents or their vapors to hightemperatures such as contact with flames, hot glowing surfaces,or electric arcs can produce decomposition products such ashydrogen chloride. Steel drums containing these solventsshould be stored in a

25、 cool, dry location, kept tightly sealed, andopened as infrequently as possible. The hydrogen chloride indecomposed solvent may harden an asphalt during the extrac-tion and recovery test.8. Sample Preparation8.1 The sample shall be obtained and handled in accordancewith Test Method D1856. This inclu

26、des the procedure forcentrifuging the solution from a previous extraction.9. Procedure9.1 Heat the oil bath to a temperature of 140 6 3C 285 65F. Circulate cold water through the condenser.9.2 Apply a vacuum of 5.3 6 0.7 kPa 40 6 5mmofHgbelow atmospheric pressure and draw approximately 600 mLof asph

27、alt solution from the sample container into the distilla-tion flask by way of the sample line. Begin a nitrogen or carbondioxide flow of approximately 500 mL/min through the system(Note 4). Begin rotating the distillation flask (at approximately40 rpm) and lower the flask into the oil bath. Initiall

28、y theimmersion depth of the flask will be determined by the need toachieve a controlled solvent evaporation rate. The correct rateof evaporation can be observed as a steady controlled stream ofcondensed solvent being collected in the recovery flask.NOTE 4The vacuum and nitrogen or carbon dioxide flo

29、w values mayneed to be adjusted depending on the location. Also, low flow values arerecommended at the beginning of the rotary process when the samplevolume is large because of the possibility of back flow into the vacuumsystem. The possibility of back flow can also be minimized by regulatingthe dep

30、th of immersion of the flask.9.3 When the amount of asphalt solution within the distil-lation flask appears low enough so that more solution may beadded, discontinue the nitrogen or carbon dioxide flow. Drawthe remaining asphalt solution from the sample container intothe distillation flask and readj

31、ust the nitrogen or carbon dioxideflow (Note 5).NOTE 5The equipment may be modified to allow a continuous flow ofsolution from the sample container into the distillation flask such that thevolume in the distillation flask is maintained at approximately 600 mL.The nitrogen or carbon dioxide flow is n

32、ot started until all the solution hasentered the distillation flask.9.4 When the bulk of the solvent has been distilled from theasphalt and no obvious condensation is occurring on the3Available from American Conference of Governmental Industrial Hygienists,1330 Kemper Meadow Drive, Cincinnati, OH 45

33、240, (513) 7422020, (www.acgi-h.org).FIG. 1 Rotary Evaporator and Recovery SystemD5404/D5404M 112condenser, immerse the flask to the recommended maximumimmersion depth of approximately 40 mm 1.5 in. Slowlyapply a vacuum of 80.0 6 0.7 kPa 600 65 mm of Hg belowatmospheric pressure. Increase nitrogen o

34、r carbon dioxide flowto approximately 600 mL/min and the spin rate of the distilla-tion flask to about 45 rpm (Note 6). Hold or reduce vacuum iffoaming or a bubbly formation occurs. When foaming subsidesapply maximum vacuum. Maintain this condition for 15 6 1min.NOTE 6It is recommended that the flas

35、k be immersed for up to 2 minbefore slowly applying the vacuum.NOTE 7A faster flask spin rate exposes more surface area of theasphalt and, hence, dislodges more traces of solvent from the asphalt. Therotation speed of the flask may also be varied or the flask rotation may bestopped to enhance the re

36、moval of solvent.NOTE 8Due to the cooling effect of the increased nitrogen or carbondioxide flow, an increase in the temperature of the oil bath is generallyneeded to maintain a constant sample temperature. Experience has shownthat a typical oil bath temperature range of 150 to 155C300 to 310F issat

37、isfactory for this purpose.9.5 At the end of the 15 min period, remove the distillationflask from the apparatus and wipe the flask clean of oil. Pourthe asphalt into a proper size container. If needed, the flask maybe inverted and placed into an oven at 165 6 1C 329 6 2Ffor 10 to 15 min to cause the

38、 asphalt to flow into the container.The asphalt should not be allowed to be distributed over theinterior of the flask.9.6 Portions of the recovered asphalt, while still in a liquidstate, can be taken for penetration, softening point, ductility,and kinematic and absolute viscosity determinations as r

39、e-quired. If ash content determinations are to be conducted, theyshall be determined in accordance with Methods D2939 andreported with other test data on the recovered asphalt.NOTE 9Ash contents of recovered asphalts greater than 1 % mayaffect the accuracy of the penetration, ductility, softening po

40、int, orviscosity tests.NOTE 10Results reported by the AASHTO Materials ReferenceLaboratory for proficiency samples from 1992 to 1996 indicate that thebetween-laboratory precision (1S%) ranges from 16 to 30 % for penetra-tion of recovered asphalt, 10 to 22 % for kinematic viscosity (135C275F), and 16

41、 to 45 % for viscosity at 60C 140F. These ranges aresignificantly larger than reported for testing original asphalts.10. Keywords10.1 bituminous paving mixtures; recovery; rotaryevaporatorASTM International takes no position respecting the validity of any patent rights asserted in connection with an

42、y item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical

43、 committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration a

44、t a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor

45、Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D5404/D5404M 113