1、Designation: D3279 07D3279 12Standard Test Method forn-Heptane Insolubles1This standard is issued under the fixed designation D3279; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses
2、 indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers determination of the mass percent of asphaltenes as defined by insolubility in normal-heptanesolvent. It is applicable to all solid
3、and semi-solid petroleum asphalts containing little or no mineral matter, to gas oils, to heavyfuel oils, and to crude petroleum that has been topped to a cut-point of 343C or higher.1.2 The values stated in SI units are to be regarded as the standard. No other units of measurement are included in t
4、his standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. See
5、 Section 7 for a specific hazard statement.2. Referenced Documents2.1 ASTM Standards:2C670 Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials3. Summary of Test Method3.1 The sample is dispersed in n -heptane and filtered through a glass-fiber pad. The in
6、soluble material is washed, dried, andweighed.4. Significance and Use4.1 This test method is useful in quantifying the asphaltene content of petroleum asphalts, gas oils, heavy fuel oils, and crudepetroleum. Asphaltene content is defined as those components not soluble in n-heptane.5. Apparatus and
7、Materials5.1 The assembly of the dispersing apparatus is illustrated in Fig. 1 with details of the component parts as follows:5.1.1 Erlenmeyer Flask, of 250-mL capacity adapted to anAllihn-type reflux condenser, each with a 35/25 ball joint.condenser.5.1.2 Magnetic Stirrer and Magnetic-Stirrer Hot P
8、late,Plate equipped with a voltage regulator.5.1.3 Bitumen Crucible or Gooch Crucible, glazed inside and outside with the exception of the outside bottom surface. Theapproximate dimensions shall be a diameter of 44 mm at the top tapering to 36 mm at the bottom and a depth of 2030mm.5.1.4 Glass Micro
9、fiber Filter Pad, glass-fiber 32 3234 mm in diameter.diameter fine porosity, fast flow rate, 1.5m particleretention.5.1.5 Filter Flask, heavy-wall with side tube, 500-mL capacity.5.1.6 Filter Tube, 40 to 42 mm in inside diameter.5.1.7 Rubber Tubing, or adapter for holding Gooch crucible on the filte
10、r tube.NOTE 1Other suitable assemblies permitting vacuum filtration with a Gooch crucible may be used.5.1.8 Oven, capable of maintaining a temperature of 110 6 5C.6. SolventReagent6.1 n-Heptane, 99.0 minimum mol % (Pure Grade).1 This test method is under the jurisdiction of ASTM Committee D04 on Roa
11、d and Paving Materials and is the direct responsibility of Subcommittee D04.47 onMiscellaneous Asphalt Tests.Current edition approved Aug. 1, 2007Dec. 1, 2012. Published August 2007December 2012. Originally approved in 1973. Last previous edition approved in 20012007as D3279 97 (2001).D3279 07. DOI:
12、 10.1520/D3279-07.10.1520/D3279-12.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an AS
13、TM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In a
14、ll cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States17. Hazards7.1 n-Heptane has a boiling point of 98C and a flash point of 1C
15、, which means that it should be handled with care. It isrecommended that both the reflux dispersion and filtration steps be conducted in a ventilated hood and away from flames or othersources of heat.8. Preparation of Crucible8.1 Place the Gooch crucible plus one thickness filter pad in an oven at a
16、bout 11065C for 30 min, allow to cool in a desiccatorfor 30 6 5 , and then determine the mass to the nearest 0.1 mg. Designate this mass as A. Store in a desicator until ready for use.9. Sample Preparation9.1 If the sample is not fluid, heat to any convenient temperature, but in any case not more th
17、an 100C above the softening point.10. Procedure10.1 Into the Note Safety precautions in Section 7. Transfer into the tared 250-mL Erlenmeyer flask, weigh to the nearest 0.1mg a quantity of the the approximate amount of sample to be tested, usingtested. Use 0.5 to 0.6 g for airblown asphalts, 0.7 toF
18、IG. 1 Dispersing ApparatusD3279 1220.8 g for asphalt paving binders and crude residues, and 1.0 to 1.3 g for gas oils and heavy fuel oils (Note 2). Allow the sampleto cool to ambient temperature and determine the nass to the nearest 1mg. Designate this mass a B.Add n-heptane in the ratio 100mL of so
19、lvent per 1 g of sample, using proportionally less or more solvent as dependent upon the sample size. Unless the asphaltis in a granular form, heat the flask gently and turn it to cause the sample to be distributed somewhat over the bottom or lowersides of the flask.NOTE 2Tests show a small amount o
20、f insolubles (60.3 mass %) remain on walls of the precipitation flask despite repeated washings. When expectedlevel of nC7 insolubles is 6 % or less, use of a tared 250-mL Erlenmeyer flask is recommended. After all possible precipitate has been washed from theflask to the filtering crucible in 8.310
21、.3, include the flask with the crucible for the drying, weighing, and calculation procedures in 8.310.3 and 9.111.1.10.2 Place the Erlenmeyer flask, containing the sample plus solvent with magnetic stirrer added, on the magnetic-stirrer hotplate and secure under the reflux condenser. With the magnet
22、ic stirrer in operation, adjust the heat for gentle refluxing for a periodof 15 to 20 min when testing paving binders, fuel oils, gas oils, or crude residues. For airblown asphalts, a reflux period of 25 to30 min is recommended. In all cases, allow the dispersed mixture to cool to room temperature f
23、or a period of 1 h.10.3 Place the Gooch crucible plus one thickness of the glass-fiber filter pad in an oven at about 107C for 15 min, allow tocool in a desiccator, and then weigh to the nearest 0.1 mg. Set up the filtering crucible plus filter pad in the suction flask and pre-wetwith 5 mL of n-hept
24、ane (see Fig. 2). Warm the flask containing the sample plus solvent to 38 to 49C on the hot plate and pourits contents (except for the magnetic stirrer) through the filter using a gentle vacuum. Filtration will proceed most rapidly if thesupernatant liquid is filtered first with the insolubles trans
25、ferred to the filter last. Police the beaker or flask while transferring thefinal precipitate, using either a rubber policeman or stainless steel spatula with a squared end. Wash the precipitate with threeportions of n-heptane of about 10 mL each, first rinsing out the flask therewith. Place the cru
26、cible in the 107C 110 6 5C ovenfor a period of 1530 min, cool in a desiccator, and weigh.determine the mass to the nearest .1 mg. Designate this mass a C.FIG. 2 Filtration ApparatusD3279 12311. Calculation and Report11.1 Calculate the mass percent of normal-heptane insolubles (NHI) as the percentage
27、 by weight of the original sample asfollows:NHI,%5A/B!3100 (1)NHI,%5(C 2A)/B!3100 (1)where:A = total mass of insolubles, andA = mass of crucible and filterB = total mass of sample.C = mass of crucible, filter, and insoluble materialFor percentages of insolubles less than 1.0, report to the nearest 0
28、.01 %; for percentages of insolubles of 1.0 or more, report tothe nearest 0.1 %.12. Precision and Bias12.1 Precision of the method has been determined as follows:Standard DeviationAAcceptable Range ofTwo ResultsASingle-operator 0.53 % NHI 1.51 % NHIMultilaboratory 0.93 % NHI 2.78 % NHI_A These numbe
29、rs represent, respectively, the (1S) and (D2S) limits as described in Practice C670. The precision is for samples covering a range from 4.0 to 29.0 % HI.13. Keywords13.1 asphaltenes; heptane insolublesASTM International takes no position respecting the validity of any patent rights asserted in conne
30、ction 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 infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsi
31、ble 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 standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful con
32、sideration at 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
33、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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).3 Glass filter pads No. 934-AH (Huribut) may be purchased from Reeve Angel and Company, Clifton, NJ.D3279 124
