ASTM D87-2009(2018) Standard Test Method for Melting Point of Petroleum Wax (Cooling Curve).pdf

《ASTM D87-2009(2018) Standard Test Method for Melting Point of Petroleum Wax (Cooling Curve).pdf》由会员分享，可在线阅读，更多相关《ASTM D87-2009(2018) Standard Test Method for Melting Point of Petroleum Wax (Cooling Curve).pdf（5页珍藏版）》请在麦多课文档分享上搜索。

1、Designation: D87 09 (Reapproved 2018) Technical Association of Pulpand Paper IndustryStandard Method T 630m-61Method 1402-Federal TestMethod Standard No. 791bBritish Standard 4695Designation: 55/77(83)Standard Test Method forMelting Point of Petroleum Wax (Cooling Curve)1This standard is issued unde

2、r the fixed designation D87; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscriptepsilon () indicates an editorial change since the

3、last revision or reapproval.1. Scope1.1 This test method covers the determination of the meltingpoint (cooling curve) of petroleum wax. It is unsuitable forwaxes of the petrolatum group, microcrystalline waxes, orblends of such waxes with paraffin wax or scale wax.NOTE 1For additional methods used f

4、or testing petroleum waxes, seeTest Method D127 and Test Method D938. Results may differ, dependingon the method used. For pharmaceutical petrolatum, Test Method D127usually is used.1.2 The values stated in SI units are to be regarded asstandard. The values given in parentheses after SI units arepro

5、vided for information only and are not considered standard.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, health, and environmental practices and deter-mi

6、ne the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations

7、 issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D127 Test Method for Drop Melting Point of PetroleumWax, Including PetrolatumD938 Test Method for Congealing Point of PetroleumWaxes, Including PetrolatumD6299 Practice for A

8、pplying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System PerformanceE1 Specification for ASTM Liquid-in-Glass Thermometers3. Terminology3.1 Definitions:3.1.1 melting point (cooling curve) of petroleum waxtemperature at which melted petroleum wax f

9、irst shows aminimum rate of temperature change when allowed to coolunder prescribed conditions.3.1.1.1 DiscussionThe so-called “American MeltingPoint” is arbitrarily 1.65 C (3 F) above the Melting Point(Cooling Curve) of Petroleum Wax.4. Summary of Test Method4.1 In Procedure A (Manual Method), a sp

10、ecimen of moltenwax in a test tube fitted with a thermometer or equivalenttemperature measuring device is placed in an air bath, which inturn is surrounded by a water bath held at 16 C to 28 C (60 Fto 80 F). As the molten wax cools, periodic readings of itstemperature are taken. When solidification

11、of the wax occurs,the rate of temperature change decreases, yielding a plateau inthe cooling curve. The temperature at that point is recorded asthe melting point (cooling curve) of the sample.4.2 In Procedure B, an automatic analyzer is used. As themolten wax cools, the sample temperature decrease i

12、s mea-sured every 15 s in 0.01 C (0.1 F) readings. The meltingpoint is considered to be reached when five consecutivemeasurements are constant within a given temperature interval,usually 0.1 C (0.2 F).5. Significance and Use5.1 Melting point (cooling curve) is a test that is widelyused by wax suppli

13、ers and consumers. it is particularly applied1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.10.0A on Physical/Chemical Properties.In the IP, this test method is under the jurisdi

14、ction of the StandardizationCommittee. This test method was adopted as a joint ASTM-IP standard in 1966.Current edition approved Oct. 1, 2018. Published November 2018. Originallyapproved in 1921. Last previous edition approved in 2014 as D87 09 (2014). DOI:10.1520/D0087-09R18.2For referenced ASTM st

15、andards, 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 website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,

16、 PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organizatio

17、n Technical Barriers to Trade (TBT) Committee.1to petroleum waxes that are rather highly paraffinic or crystal-line in nature. A plateau occurs with specimens containingappreciable amounts of hydrocarbons that crystallize at thesame temperature, giving up heat of fusion, thus temporarilyretarding th

18、e cooling rate. In general, petroleum waxes withlarge amounts of non-normal hydrocarbons or with amorphoussolid forms will not exhibit a plateau.6. Apparatus6.1 The necessary apparatus for Procedure A is described inAnnex A1.6.2 The automatic instrument consists of a bath (forexample, an aluminum bl

19、ock with two measuring locations,two apertures to place the test tubes, and two apertures for thetemperature probes). The apparatus may have an accessorydigital display and a printer.6.2.1 The temperature of the bath is maintained between22 C and 26 C (72 F and 79 F). A heating device is used toincr

20、ease the temperature, and a cooling device with cold watercirculation is used to decrease the temperature.6.2.2 The temperature may be monitored with a calibratedthermometer or an electronic temperature measuring device ofequivalent precision and accuracy.6.3 Other types of equivalent automatic appa

21、ratus are ac-ceptable.7. Test Specimen7.1 Obtain a sample of wax representative of the shipmentto be tested. From each test unit obtain a portion of waxweighing at least 25 g for each melting point determination.8. Procedure A (Manual Method)8.1 Support the air bath in its proper position in the wat

22、erbath. Fill the water bath to within 13 mm (12 in.) of the topwith water at a temperature of 16 C to 28 C (60 F to 80 F).The bath temperature is kept within these limits throughout thetest.8.2 Heat the wax sample to at least 8 C (15 F) above itsexpected melting point (see Note 2). To heat the wax s

23、ampleuse a suitable container in an oven or water bath which is heldat a temperature not exceeding 93 C (200 F).Avoid the use ofdirect heat such as flame or hot plate. Do not keep the samplein the molten state longer than 1 h.NOTE 2If no estimate of the melting point is available, heat the waxsample

24、 to 10 C (15 F) above the temperature at which the wax iscompletely molten, or to from 90 C to 93 C (195 F to 200 F) beforeproceeding to the next step.8.3 Fill the test tube to a height of 51 mm (2 in.) with themelted sample. Insert the melting point temperature measuringdevice through the center of

25、 a one-holed stopper, such as acork. In the case of a thermometer, position the 79 mm (318 in.)immersion line at the lower surface of the stopper. Insert thestopper into the test tube so that the bottom of the thermometerbulb or temperature measuring probe is 10 mm (38 in.) fromthe bottom of the tes

26、t tube. Support the test tube assembly inthe air bath, as shown in Fig.A1.1, while the temperature of themolten wax is still at least 8 C (15 F) above its expectedmelting point (Note 2).8.4 Take a temperature reading every 15 s. Record eachreading to at least the nearest 0.05 C (0.1 F). Monitor thep

27、rogress of these sequential readings to determine the appear-ance of the plateau. Identify the plateau as the first fiveconsecutive readings all of which agree within 0.1 C (0.2 F).You may discontinue the test after obtaining these five plateaureadings.NOTE 3If no plateau appears as defined above, t

28、he reading procedureis continued until either (1) the temperature reached 38 C (100 F) or (2)the temperature reaches a point 8 C (15 F) below a temperature wherethe wax has solidified (as may be observed through a transparent bath). Ineither of these cases the test is discontinued and the method is

29、judged NotApplicable for the sample (see Note 1 for other methods).9. Procedure B (Automatic Method)9.1 Place a clean test tube held in a PTFE holder ring in theaperture provided in the apparatus.9.2 Insert the temperature probe into a centrally bored,one-holed stopper, and insert it in the test tub

30、e. Check theprobe height to reach manufacturers suggested height. Placethe stopper with the probe back in the resting holder provided.9.3 Bring the sample to a temperature at least 8 C (15 F)above the expected melting point. Heat the sample in a 93 C(200 F) maximum temperature water bath.9.4 Add the

31、 molten sample to the test tube to the fillingmark. Place the stopper with the probe on the test tubeassembly.9.5 Insert the assembly into the aluminum block aperture,and initiate the analysis in accordance with the manufacturersinstructions.9.6 When the melting point is detected, the analysis willa

32、utomatically stop. Per available options on the instrument, theresulting melting point will be displayed on the digital monitor,or printed on a printer, or both.10. Calculation and Report10.1 When using a manual apparatus, average the first fiveconsecutive temperature readings of the identified plat

33、eau,which agree within 0.1 C (0.2 F). Correct this average forerror in the thermometer scale where necessary.10.2 The automatic apparatus will average the first fiveconsecutive temperature probe readings within 60.1 C(60.2 F).10.3 Report the result to at least the nearest 0.05 C (0.1 F)as the Petrol

34、eum Wax Melting Point (Cooling Curve), TestMethod D87. Also report whether the test was performedmanually or using automatic apparatus, as applicable.11. Quality Control (QC)11.1 Confirm the performance of the instrument or the testprocedure by analyzing a quality control (QC) sample.11.1.1 When QC/

35、Quality Assurance (QA) protocols arealready established in the testing facility, these may be usedwhen they confirm the reliability of the test result.11.1.2 When there is no QC/QA protocol established in thetesting facility, Appendix X1 can be used as the QC/QAsystem.D87 09 (2018)212. Precision and

36、 Bias312.1 PrecisionThe precision of this test method as deter-mined by statistical examination of interlaboratory results is asfollows:12.1.1 RepeatabilityThe difference between two testresults, obtained by the same operator with the same apparatusunder constant operating conditions on identical te

37、st material,would in the long run, in the normal and correct operation ofthe test method, exceed the following values only in one casein twenty:Manual apparatus 0.11 CAutomatic apparatus 0.23 C12.1.2 ReproducibilityThe difference between two singleand independent results obtained by different operat

38、ors 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:Manual apparatus 0.41 CAutomatic apparatus 0.50 C12.2 This test method is considered suitable for waxe

39、s of amelting point between 38 C (100 F) and 82 C (180 F).These precision values have been obtained by statisticalexamination of interlaboratory test results from 2005. Thesevalues are based on a study among 14 laboratories, using sevenparaffin waxes with a melting point range of 52 C to 70 C(126 F

40、to 158 F).12.3 BiasThe bias of this test method cannot be deter-mined since no generally acceptable standard reference mate-rial is available for this analysis.12.4 Relative BiasThe sample set was analyzed usingboth manual and automatic apparatus. The difference betweenthe two sets of measurements w

41、as not very significant. Auto-matic mode results were biased very slightly low (averaging0.064 difference).12.4.1 Based on the comparison of analysis of three sets ofwax samples in the melting point range of 115 F to 159 F (atotal of 70 data points by each method) by both manual andautomatic apparat

42、us in one laboratory, a correlation coefficientof r2of 0.9999 was obtained indicating that there is no biasbetween the two modes of measurement.13. Keywords13.1 cooling curve; melting point; petroleum wax; waxANNEX(Mandatory Information)A1. APPARATUSA1.1 Test TubeA standard glass test tube, 25 mm (1

43、 in.)in outside diameter, and 100 mm (4 in.) in length. It may bemarked with a reference line for sample filling at 51 mm (2 in.)above the bottom, and a reference line for positioning of thebottom of the temperature measuring device at 10 mm (38 in.)above the bottom.A1.2 Air BathAcylinder 51 mm (2 i

44、n.) in inside diameterand 114 mm (412 in.) in depth, equipped to hold the test tubefirmly in a vertical position in the center of the air bath. Asexamples, a tight-fitting cork having a central opening or ametal plate top with a spring clamp that holds the test tubefirmly in place have been found su

45、itable to use.A1.3 Water BathA suitable cylindrical vessel, 130 mm(518 in.) in inside diameter and 152 mm (6 in.) in depth.Provide a fitted cover equipped to support the air bathvertically so that the sides and bottom of the air bath aresurrounded by a layer of water 38 mm (112 in.) thick. Provideth

46、e cover with an opening through which the bath temperaturemeasuring device may be suspended 19 mm (34 in.) from theoutside wall of the water bath.NOTE A1.1The air bath, water bath, and water bath cover may bemade in one assembly as shown in Fig. A1.1.A1.4 Melting Point ThermometerA wax melting point

47、thermometer having the range shown below and conforming tothe requirements as prescribed in Specification E1 or in thespecifications for IP thermometers:Thermometer NumberTemperature Range ASTM IP38 C to 82 C 14C 17C100 F to 180 F 14F 17FNOTE A1.2Other means of monitoring the temperature (for exampl

48、e,a resistance temperature detector, in conjunction with a data logger orcomputer) may be used in place of the specified melting pointthermometer, provided that the results are found to be statisticallyequivalent and that the laboratory making the substitution has collectedthe necessary data to demo

49、nstrate this equivalency.A1.5 Bath Temperature Measuring DeviceAny suitablepartial immersion thermometer, or other equivalent device,accurate to at least 1.0 C (2 F) throughout the required range.A1.6 TimerInterval timer or stop watch.3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D02-1617. ContactASTM CustomerService at serviceastm.org.D87 09 (2018)3APPENDIX(Nonmandatory Information)X1. QUALITY CONTROL MONITORING