1、Designation: D 5404 03Standard Practice forRecovery of Asphalt from Solution Using the RotaryEvaporator1This standard is issued under the fixed designation D 5404; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last re
2、vision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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 inthe asphalt
3、properties during the recovery process are mini-mized.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are provided forinformation only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is
4、theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:D 92 Test Method for Flash and Fire Points by ClevelandOpen Cup2D 1856 Test Method fo
5、r Recovery of Asphalt from Solutionby Abson Method3D 2939 Test Methods for Emulsified Bitumens Used asProtective Coatings4D 6368 Specification for Vapor-Degreasing Grade and Gen-eral Solvent Grade Normal-Propyl Bromide52.2 Federal Specification:O-T-634 (latest) Trichloroethylene, Technical63. Summar
6、y of Practice3.1 The solution of solvent and asphalt 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 recov
7、ered asphalt can then besubjected to testing as required.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 so
8、lvent without significantlychanging the asphalts properties. 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.5. Apparatus5.1 Rotary Ev
9、aporator (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 approximately
10、 15.The distillation flask (Note 1), when fully immersed, should beat a depth of approximately 40 mm (1.5 in.).7NOTE 1A flask having a 2000 mL capacity is recommended.5.2 Manometer or Vacuum Gage, suitable for measuring thespecified vacuum.5.3 Gas Flowmeter, capable of indicating a gas flow of up to
11、1000 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 Hg) of the desired level up to andincluding 80 kPa (600 mm Hg).6. Reagents and Materials6.1 Nitrogen Gas or Carbon Dioxide GasA pre
12、ssurizedtank with pressure-reducing valve, or other convenient source.NOTE 2Different flow rates may be required depending on whethernitrogen gas or carbon dioxide gas is used.1This practice is under the jurisdiction of ASTM Committee D04 on Road andPaving Materials and is the direct responsibility
13、of Subcommittee D04.25 onAnalysis of Bituminous Mixtures.Current edition approved Feb. 10, 2003. Published May 2003. Originallyapproved in 1997. Last previous edition approved in 2002 as D 5404 02.2Annual Book of ASTM Standards, Vol 05.01.3Annual Book of ASTM Standards, Vol 04.03.4Annual Book of AST
14、M Standards, Vol 04.04.5Annual Book of ASTM Standards, Vol 15.05.6Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.7The Buchi Rotavapor RE-111A, or its equivalent, has been found satisfactoryfor this purpose. The Buchi
15、Rotavapor is available from Fischer Scientific,Pittsburgh, PA.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2 OilThe oil for the heated oil bath should be USPWhite Oil or Silicone Fluid SWS-101 with flash point above215C (420F) o
16、r an equivalent. The flash point is determinedin accordance with Test Method D 92.6.3 Solvents:6.3.1 Trichloroethylene and Methylene ChlorideThe sol-vent for extracting the asphalt from mixtures should be reagentgrade trichloroethylene or methylene chloride. A technicalgrade of trichloroethylene may
17、 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 asphalt from the mixtures should conform toSpecification D 6368. Because there may be some interactionsdue to d
18、ifferences 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 should be used onlyunder a hood or with an effective surface exhaust system in awell ventilated area, since they
19、 are toxic to various degrees.Consult the current Threshold Limit Concentration Committeeof the American Conference of Governmental Industrial Hy-gienists8for the current threshold limit values.7.2 These solvents in the presence of heat and moisture maybe hydrolyzed to form acids that are extremely
20、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 theeffluent tanks of aluminum vacuum extractors.7.3 Exposure of these solvents or their vapors to hightemperatu
21、res 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 cool, dry location, kept tightly sealed, andopened as infrequently as possible. The hydrogen chloride indecom
22、posed 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 D 1856. This includes the procedure forcentrifuging the solution from a previous extraction.9. Procedure9.1 Heat the oil bath t
23、o 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 5mmHg)below atmospheric pressure and draw approximately 600 mLof asphalt solution from the sample container into the distilla-tion flask by way of the sample line. Begin a nitr
24、ogen or carbondioxide flow of approximately 500 mL/min through the system(Note 3). Begin rotating the distillation flask (at approximately40 rpm) and lower the flask into the oil bath. Initially theimmersion depth of the flask will be determined by the need toachieve a controlled solvent evaporation
25、 rate. The correct rateof evaporation can be observed as a steady controlled stream ofcondensed solvent being collected in the recovery flask.NOTE 3The vacuum and nitrogen or carbon dioxide flow values mayneed to be adjusted depending on the location. Also, low flow values arerecommended at the begi
26、nning 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 depth of immersion of the flask.9.3 When the amount of asphalt solution within the distil-lation flask appears
27、 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 readjust the nitrogen or carbon dioxideflow (Note 4).NOTE 4The equipment may be modified to allow a continuous f
28、low 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 not started until all the solution hasentered the distillation flask.9.4 When the bulk of the solvent has be
29、en distilled from theasphalt and no obvious condensation is occurring on thecondenser, 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 Hg) belowatmospheric pressure. Increase nitrogen or carbon dioxide fl
30、owto approximately 600 mL/min and the spin rate of the distilla-tion flask to about 45 rpm (Note 5). to 2 min delay beforeapplying the vacuum is recommended. Hold or reduce vacuumif foaming or a bubbly formation occurs. When foamingsubsides apply maximum vacuum. Maintain this condition for15 6 1 min
31、.NOTE 5A 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 removal of solvent.NOTE 6Due to the cooling effect of the increa
32、sed 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 300 to 315F (148.9 to157.2C) is satisfactory for this purpose.9.5 At the end of the 15 min
33、 period, remove the distillationflask from the apparatus and wipe the flask clean of oil. Pour8Available from American Conference of Governmental Industrial Hygienists,1330 Kemper Meadow Drive, Cincinnati, OH 45240, (513) 7422020, (www.acgi-h.org).FIG. 1 Rotary Evaporator and Recovery SystemD5404032
34、the asphalt into a proper size container. If needed, the flask maybe inverted and placed into an oven at 165 6 1C (329 6 2F)for 10 to 15 min to cause the 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
35、 asphalt, while still in a liquidstate, can be taken for penetration, softening point, ductility,and kinematic and absolute viscosity determinations as re-quired. If ash content determinations are to be conducted, theyshall be determined in accordance with Methods D 2939 andreported with other test
36、data on the recovered asphalt.NOTE 7Ash contents of recovered asphalts greater than 1 % mayaffect the accuracy of the penetration, ductility, softening point, orviscosity tests.NOTE 8Results reported by the AASHTO Materials Reference Labo-ratory for proficiency samples from 1996 to 1992 indicate tha
37、t thebetween-laboratory precision (1S%) ranges from 16 to 30 % for penetra-tion of recovered asphalt, 10 to 22 % for kinematic viscosity (135C), and16 to 45 % for viscosity at 60C. These ranges are significantly larger thanreported for testing original asphalts.10. Keywords10.1 bituminous paving mix
38、tures; recovery; rotaryevaporatorASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof
39、 infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this s
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41、r views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor 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).D5404033
