1、Designation: D 3235 06An American National StandardStandard Test Method forSolvent Extractables in Petroleum Waxes1This standard is issued under the fixed designation D 3235; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、 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.1. Scope*1.1 This test method covers the determination of solventextractables in petroleum waxes.1.2 The values stated in SI
3、units are to be regarded as thestandard. The values given in parentheses are for informationonly.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
4、practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E1 Specification for ASTM Liquid-in-Glass ThermometersE 128 Test Method for Maximum Pore Diameter and Per-meability of Rigid Porous Filters for Laboratory Use3. Summary of Tes
5、t Method3.1 The sample is dissolved in a mixture consisting of 50volume % methyl ethyl ketone and 50 volume % toluene. Thesolution is cooled to 32C (25F) to precipitate the wax,then filtered. The solvent extractables content is determined byevaporating the solvent from the filtrate and weighing ther
6、esidue.4. Significance and Use4.1 The solvent extractables in a wax may have significanteffects on several of its properties such as strength, hardness,flexibility, scuff resistance, coefficient of friction, coefficient ofexpansion, melting point, and staining characteristics. Whetherthese effects a
7、re desirable or undesirable depends on theintended use of the wax.5. Apparatus5.1 Filter Stick and Assembly, consisting of a 10-mmdiameter sintered glass filter stick of 10 to 15 m maximumpore diameter as determined by the method in Appendix X1,provided with an air pressure inlet tube and delivery n
8、ozzle. Itis provided with a ground-glass joint to fit a 25 by 170-mm testtube. The dimensions for a suitable filtration assembly areshown in Fig. 1.NOTE 1A metallic filter stick may be employed if desired. A filterstick3made of stainless steel and having a 12.7-mm (0.50-in.) disk of 10to 15 nm maxim
9、um pore diameter, as determined by Test Method E 128,has been found to be satisfactory. The metallic apparatus is inserted intoa 25 by 150-mm test tube and held in place by means of a cork.5.2 Cooling Bath, consisting of an insulated box with 30 65-mm (1.2 6 0.2-in.) holes in the center to accommoda
10、te anydesired number of test tubes. The bath may be filled with asuitable medium such as kerosine, and may be cooled bycirculating a refrigerant through coils, or by using solid carbondioxide. A suitable cooling bath to accommodate three testtubes is shown in Fig. 2.5.3 Dropper Pipet, dispensing dev
11、ice capable of delivering0.5 6 0.05 g of molten wax.5.4 Transfer Pipet, or equivalent volume dispensing device,capable of delivering 15 6 0.06 mL.5.5 Air Pressure Regulator, designed to supply air to thefiltration assembly (8.5) at sufficient pressure to give an evenflow of filtrate. Either a conven
12、tional pressure-reducing valveor a mercury bubbler-type regulator has been found satisfac-tory. The latter type, illustrated in Fig. 3, consists of a 250-mLglass cylinder and a T-tube held in the cylinder by means of a1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Prod
13、ucts and Lubricants and is the direct responsibility of SubcommitteeD02.10.0A on Physical/Chemical Properties.Current edition approved Nov. 1, 2006. Published November 2006. Originallyapproved in 1973. Last previous edition approved in 2005 as D 323505.2For referenced ASTM standards, visit the ASTM
14、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.3The sole source of supply of a suitable metal filter stick with designatedporosity G known to the committee
15、 at this time is the Pall Trinity Micro Corp.,Route 281, Cortland, NY13045.Alist of United Kingdom suppliers can be obtainedfrom Energy Institute, 61 New Cavendish St., London, W1G 7AR, United King-dom. If you are aware of alternative suppliers, please provide this information toASTM International H
16、eadquarters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee,1which you may attend.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-29
17、59, United States.rubber stopper grooved at the sides to permit the escape ofexcess air. The volume and pressure of the air supplied to thefiltration assembly is regulated by the depth to which theT-tubeis immersed in mercury at the bottom of the cylinder. Absor-bent cotton placed in the space above
18、 the mercury prevents theloss of mercury by spattering. The air pressure regulator isconnected to the filter stick and assembly by means of rubbertubing.5.6 Temperature Measuring Devices:5.6.1 Thermometers, two, having a range as shown belowand conforming to the requirements as prescribed in Specifi
19、-cation E1or in the specifications for IP Standard Thermom-eters. One thermometer is required for the cold bath and asecond thermometer is required for the sample solution.Thermometer NumberTemperature Range ASTM IP37 to +21C 71C 72C35 to +70F 71F 72F5.6.2 Temperature measuring devices other than th
20、ose de-scribed in 5.6.1 are satisfactory for this test method, providedthey exhibit the same temperature response as the equivalentmercury-in-glass thermometers.5.7 Weighing Bottles, glass-stoppered, having a typical ca-pacity of 15-25 mL.5.8 Evaporation Assembly, consisting of an evaporatingcabinet
21、 and connections, essentially as illustrated in Fig. 4, andcapable of maintaining a temperature of 35 6 1C (95 6 2F)around the evaporation flasks. Construct the jets with an insidediameter of 4 6 0.2 mm for delivering a stream of clean, dryair vertically downward into the weighing bottle. Support ea
22、chjet so that the tip is 15 6 5 mm above the surface of the liquidat the start of the evaporation. Supply purified air at the rate of2 to 3 L/min per jet. One way to purify the air is to pass itthrough a tube of approximately 1-cm bore packed loosely toa height of approximately 20 cm with absorbent
23、cotton.Periodically check the cleanliness of the air by evaporating 4mL of the solvent mixture described in 6.3 by the procedurespecified in 8.5. When the residue does not exceed 0.1 mg, theevaporation equipment is operating satisfactorily.NOTE 2Investigations by the European World Federation have i
24、ndi-cated that improved precision may be achieved by individually calibratingeach nozzle to deliver a flow rate of 2 to 3 L/min.5.9 Analytical Balance, capable of reproducing weights to0.1 mg.5.10 Wire StirrerA piece of stiff made of iron, stainlesssteel, or Nichrome wire of about No. 20 Bands (0.9
25、mm indiameter) or 16 swg. gage, 250 mm long. A 10-mm diameterloop is formed at each end, and the loop at the bottom end isbent so that the plane of the loop is perpendicular to the wire.6. Solvent6.1 Methyl Ethyl Ketone, conforming to the specifications ofthe Committee onAnalytical Reagents of theAm
26、erican Chemi-cal Society.46.2 Toluene, conforming to the specifications of the Com-mittee on Analytical Reagents of the American ChemicalSociety.44Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlist
27、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. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.All dimensions are in millimetres.FIG. 1 Filter StickD32350626.3 Solven
28、t MixturePrepare a mixture of 50 volume %methyl ethyl ketone and 50 volume % toluene.6.4 Store the solvent mixture over anhydrous calcium sul-fate (5 weight % of the solvent). Filter prior to use.7. Sample7.1 Obtain a representative portion by melting the entiresample and stirring thoroughly. This i
29、s necessary because theextractables may not be distributed uniformly throughout thesolidified sample.8. Procedure8.1 Melt a representative portion of the sample, using awater bath or oven maintained at 70 to 100C (158 to 212F).As soon as the wax is completely melted, thoroughly mix.Preheat the pipet
30、 or equivalent measuring device in order toprevent the solidification of wax in the tip, and withdraw aportion of the sample as soon as possible after the wax hasmelted. The mass of wax transferred to the test tube must be1.00 6 0.05 g.Allow the test tube to cool, and weigh to at leastthe nearest 1
31、mg.NOTE 3The weight of a test tube which is cleaned by means ofsolvent will not vary to a significant extent. Therefore, a tare weight maybe obtained and used repeatedly.8.2 Pipet 15 mLof the solvent mixture into the test tube andplace the latter just up to the level of its contents in a hot wateror
32、 steam bath. Heat the solvent-wax mixture, stirring up anddown with the wire stirrer, until a homogeneous solution isobtained. Exercise care to avoid loss of solvent by prolongedboiling.NOTE 4Very high-melting wax samples may not form clear solutions.Stir until the undissolved material is well dispe
33、rsed as a fine cloud.All dimensions are in millimetres (inches).FIG. 2 Cooling BathD32350638.2.1 Plunge the test tube into an 800-mL beaker of icewater and continue to stir until the contents are cold. Removethe stirrer. Remove the test tube from the ice bath, wipe dry onthe outside with a cloth, an
34、d weigh to at least the nearest 0.1 g.NOTE 5During this operation the loss of solvent through vaporizationshould be less than 1 %. The weight of the solvent is, therefore, practicallya constant, and after a few samples are weighed, this weight can be usedas a constant factor.8.3 Place the test tube
35、containing the wax-solvent slurry inthe cooling bath, which is maintained at 34.5 6 1.0C (30.06 2.0F). During this chilling operation, stir the contents of thetube by means of a temperature measurement device placed inthe tube. It is important that stirring by means of the tempera-ture measurement d
36、evice be almost continuous, in order tomaintain a slurry of uniform consistency as the wax precipi-tates. Do not allow the wax to set up on the walls of the coolingvessel nor permit any lumps of wax crystals to form. Continuestirring until the temperature reaches 31.7 6 0.3C (25.0 60.5F).8.4 Remove
37、the temperature measurement device from thetube and allow it to drain momentarily into the tube, thenimmediately immerse in the mixture the clean, dry filter stick,which has previously been cooled by placing it in a test tubeand holding at 34.5 6 1.0C (30.0 6 2.0F) in the coolingbath for a minimum o
38、f 10 min. Seat the ground-glass joint ofthe filter so as to make an airtight seal. Place an unstopperedweighing bottle, previously weighed together with the glassstopper to the nearest 0.1 mg, under the delivery nozzle of thefiltration assembly.NOTE 6Take every precaution to ensure the accuracy of t
39、he weight ofthe stoppered weighing bottle. Prior to determining this weight, rinse theclean, dry weighing bottle and stopper with the solvent mixture describedin 6.3, wipe dry on the outside with a cloth, and place in the evaporationassembly to dry for about 5 min. Then remove the weighing bottle an
40、dstopper, place near the balance, and allow to stand for 10 min prior toweighing. Stopper the bottle during this cooling period. Once theweighing bottle and stopper have been dried in the evaporation assembly,lift only with forceps. Take care to remove and replace the glass stopperwith a light touch
41、.8.5 Apply air pressure to the filtration assembly and imme-diately collect about 4 mL of filtrate in the weighing bottle.Release the air pressure to permit the liquid to drain backslowly from the delivery nozzle. Remove the weighing bottleimmediately, and stopper and weigh to at least the nearest 1
42、0mg without waiting for it to come to room temperature.Unstopper the weighing bottle and place it under one of the jetsin the evaporation assembly maintained at 35 6 1C (95 62F), with the air jet centered inside the neck, and the tip 15 65 mm above the surface of the liquid. After the solvent haseva
43、porated, which usually takes less than 30 min, remove thebottle, stopper, and place near the balance. Allow to stand for10 min and weigh to the nearest 0.1 mg. Repeat the evaporationprocedure, using 5 min evaporation periods, until the lossbetween successive weighings is not over 0.2 mg.9. Calculati
44、on9.1 Calculate the amount of extractables in the wax asfollows:Solvent extractables, weight % 5 100 AC/BD (1)where:A = weight of extractables residue, g,B = weight of wax sample, g,C = weight of solvent, g, obtained by subtracting weight oftest tube plus wax sample (8.1) from weight of testtube and
45、 contents (8.2), andD = weight of solvent evaporated, in g, obtained by sub-tracting weight of weighing bottle plus extractablesresidue from weight of weighing bottle plus filtrate(8.5).10. Report10.1 Report the result as solvent extractables, weight %,Test Method D 3235. If the result is negative,
46、report as zero.11. Precision and Bias11.1 The precision of this test method as determined bystatistical examination of interlaboratory results is as follows:11.1.1 RepeatabilityThe difference between two test re-sults, obtained by the same operator with the same apparatusunder constant operating con
47、ditions on identical test materialwould, in the long run, in the normal and correct operation ofthe test method, exceed the following values only in one casein twenty:Range Repeatability15 to 55 % 2 %11.1.2 ReproducibilityThe difference between two singleand independent results obtained by different
48、 operators work-ing in different laboratories on identical test material would, inthe long run, in the normal and correct operation of the testmethod, exceed the following values only in one case intwenty:Range Reproducibility15 to 55 % 5 %All dimensions are in millimetres.FIG. 3 Air Pressure Regula
49、torD323506411.2 The procedure in this test method has no bias becausethe value of solvent extractables can be defined only in termsof a test method.12. Keywords12.1 petroleum waxes; solvent extractables; waxAll dimensions are in millimetres (inches).FIG. 4 Evaporation AssemblyD3235065APPENDIX(Nonmandatory Information)X1. TEST METHOD OF TEST FOR MEASUREMENT OF MAXIMUM PORE DIAMETEROF RIGID POROUS FILTERSX1.1 ScopeX1.1.1 This test method covers the determination of theacceptability of porous filter sticks used for filtration in TestMethod D 3235. T
