1、Designation: D3235 06 (Reapproved 2011)Standard Test Method forSolvent Extractables in Petroleum Waxes1This standard is issued under the fixed designation D3235; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revi
2、sion. A number in parentheses 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 the determination of solventextractables in petroleum waxes.1.2 The values stated in SI units are to be
3、 regarded asstandard. 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 practices and deter
4、mine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E1 Specification for ASTM Liquid-in-Glass ThermometersE128 Test Method for Maximum Pore Diameter and Per-meability of Rigid Porous Filters for Laboratory Use3. Summary of Test Method3.1 The samp
5、le 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 theresidue.4. Significan
6、ce 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 are desirable or unde
7、sirable 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 nozzle. Itis provided
8、 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 maximum pore diameter, as
9、 determined by Test Method E128,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 accommodate anydesired number
10、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 device capable of delive
11、ring0.5 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 conventional pressure-reduc
12、ing 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 arubber stopper grooved at the sides to permit the escape ofexcess air. The volume and pressure of the a
13、ir 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 the mercury prevents the1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubri
14、cants and is the direct responsibility of SubcommitteeD02.10.0A on Physical/Chemical Properties.Current edition approved Oct. 1, 2011. Published October 2011. Originallyapproved in 1973. Last previous edition approved in 2006 as D3235 - 06. DOI:10.1520/D3235-06R11.2For referenced ASTM standards, vis
15、it 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.3The sole source of supply of a suitable metal filter stick with designatedporosity G known to t
16、he committee 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 Int
17、ernational Headquarters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee,1which you may attend.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.loss of mercury by spattering. The a
18、ir 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-cation E1 or in the specifications for IP Standard Thermom-e
19、ters. 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 those de-scribed in 5.6.1 are satisfactory for this test metho
20、d, 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 and connections, essentially as illustrated in Fig. 4, andc
21、apable 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 eachjet so that the tip is 15 6 5 mm above the surface of the
22、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 cotton.Periodically check the cleanliness of the air by evap
23、orating 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 indi-cated that improved precision may be achieved by individ
24、ually 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 mm indiameter) or 16 swg. gage, 250 mm long. A 10-mm diamete
25、rloop 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 theAmerican Chemi-cal Society.46.2 Toluene, conforming to the spe
26、cifications of the Com-mittee on Analytical Reagents of the American ChemicalSociety.46.3 Solvent 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.4Reagent
27、 Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand Na
28、tional Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.All dimensions are in millimetres.FIG. 1 Filter StickD3235 06 (2011)27. Sample7.1 Obtain a representative portion by melting the entiresample and stirring thoroughly. This is necessary because theextractables may not be distr
29、ibuted 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 or equivalent measuring device in order toprevent t
30、he 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 mg.NOTE 3The weight of a test tube which is cleaned
31、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 steam bath. Heat the solvent-wax mixture, stirring
32、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 dispersed as a fine cloud.8.2.1 Plunge the test tube into
33、 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, and weigh to at least the nearest 0.1 g.NOTE 5During this operation the loss of solvent through vaporizationshould be less t
34、han 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 containing the wax-solvent slurry inthe cooling bath, which is maintained at 34.5 6 1.0C (30.0All dimensions are in millim
35、etres (inches).FIG. 2 Cooling BathD3235 06 (2011)36 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 device be almost continuous, in order tomaint
36、ain 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 the temperature measurement device from thet
37、ube 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 of 10 min. Seat the ground-glass joint ofthe
38、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 the weight ofthe stoppered weighing bottle. P
39、rior 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 andstopper, place near the balance, and allow
40、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.8.5 Apply air pressure to the filtration as
41、sembly 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 10mg without waiting for it to come to room t
42、emperature.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 hasevaporated, which usually takes less than 30 mi
43、n, 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. Calculation9.1 Calculate the amount of extractables i
44、n 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 contents (8.2), andD = weight of solvent ev
45、aporated, 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 D3235. If the result is negative, report as zero.11. Precision and Bias11.1 The
46、 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 conditions on identical test materialwould, in t
47、he 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 operators work-ing in different laboratories
48、 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 %11.2 The procedure in this test method has no bias becausethe value of solvent extractables can be define
49、d only in termsof a test method.12. Keywords12.1 petroleum waxes; solvent extractables; waxAll dimensions are in millimetres.FIG. 3 Air Pressure RegulatorD3235 06 (2011)4APPENDIX(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 D3235. This method establishes the maximum porediameter and also provides a means of detecting and measuringchanges which
