1、Designation: D 2111 02 (Reapproved 2007)Standard Test Methods forSpecific Gravity and Density of Halogenated OrganicSolvents and Their Admixtures1This standard is issued under the fixed designation D 2111; the number immediately following the designation indicates the year oforiginal adoption or, in
2、 the case of revision, the year 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 T
3、hese test methods cover the determination of thespecific gravity of halogenated organic solvents and solventadmixtures. They define suitable apparatus and procedures andfurnish details underlying the interpretation of test data and theselection of numerical limits for agreement among interestedperso
4、ns and agencies.1.2 Three methods are covered as follows:1.2.1 Method A, specific gravity by means of a hydrometer.1.2.2 Method B, specific gravity and density by means of apycnometer.NOTE 1In referee problems, Method B may be used.1.2.3 Method C, specific gravity and density by means of anelectroni
5、c densitometer.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 determine the applica-bility of regulatory limitations prior to use.
6、2. Referenced Documents2.1 ASTM Standards:2E1 Specification for ASTM Liquid-in-Glass ThermometersE 100 Specification for ASTM Hydrometers3. Terminology3.1 Definitions:3.1.1 specific gravitythe ratio of the mass in air of a givenvolume of the material at a stated temperature to the mass in airof an e
7、qual volume of distilled water at a stated temperature.3.1.1.1 DiscussionWhen the temperature of the materialand of the water are the same, the specific gravity of thematerial is expressed as follows:Specific gravity x/xC, example 25/25C (1)When the temperature of the material and of the water are n
8、ot thesame, the specific gravity of the material is expressed as follows:Specific gravity x/yC, example 20/4C (2)Note that when the density of water is expressed as 4C, the specificgravity at the stated temperature is the same as density at the statedtemperature. For example, SG 20/4C = density at 2
9、0C.When using an electronic densitometer to determine specific gravity,the temperature of the material to be tested and the water reference willbe the same. Examples 25/25C, 20/20C.3.1.2 densitythe mass of a given material per unit volume.3.1.2.1 DiscussionDensity for chlorinated solvents is nor-mal
10、ly stated in grams per cubic centimetre. Pounds per gallonis also commonly used.4. Significance and Use4.1 The density or specific gravity of a pure chlorinatedsolvent at a given temperature is constant. Density or specificgravity can be used in identification of materials, the assay ofbinary mixtur
11、es, and as an indication of purity of a givensolvent.5. Test Temperatures5.1 ASTM specifications normally state the temperaturesfor specific gravity of halogenated organic solvents at 25/25C.20/20C and 60/60F are other commonly used temperatures.METHOD ASPECIFIC GRAVITY BY MEANSOF A HYDROMETER6. App
12、aratus6.1 HydrometerThe hydrometers to be used shall be thosespecified in Specification E 100, as follows:Nominal Specific Gravity Range ASTM Hydrometer No.0.900 to 0.950 107H0.950 to 1.000 108H1.000 to 1.050 125H1.050 to 1.100 126H1These test methods are under the jurisdiction of ASTM Committee D26
13、 onHalogenated Organic Solvents and Fire Extinguishing Agents and are the directresponsibility of Subcommittee D26.04 on Test Methods.Current edition approved Feb. 1, 2007. Published February 2007. Originallyapproved in 1962. Last previous edition approved in 2002 as D 2111 02.2For referenced ASTM s
14、tandards, 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocke
15、n, PA 19428-2959, United States.1.100 to 1.150 127H1.150 to 1.200 128H1.200 to 1.250 129H1.250 to 1.300 130H1.300 to 1.350 131H1.350 to 1.400 132H1.400 to 1.450 133H1.450 to 1.500 134H1.500 to 1.550 135H1.550 to 1.600 136H1.600 to 1.650 137H6.2 Hydrometer CylinderThe vessel in which the samplefor th
16、e gravity test is confined shall be made of clear glass andshall be cylindrical in shape. For convenience in pouring, itmay have a lip on the rim. The inside diameter shall be at least25.0 mm (1.0 in.) greater than the outside diameter of thehydrometer used in it. The height of the cylinder shall be
17、 suchthat the length of the column of sample it contains is greater byat least 25.0 mm than the portion of the hydrometer that isimmersed beneath the surface of the sample after a state ofequilibrium has been reached.6.3 Thermometer An ASTM Gravity Thermometer hav-ing a range from 20 to + 102C and c
18、onforming to therequirements for Thermometer 12C as prescribed in Specifi-cation E1.6.4 Water Bath, capable of maintaining the test temperature6 0.5C during the test.7. Procedure7.1 Cool the sample in the original container to about 1Cbelow the test temperature. Rinse each piece of equipment witha p
19、ortion of the sample. Pour the sample into the cleanhydrometer cylinder without splashing, so as to avoid forma-tion of air bubbles. Remove any air bubbles adhering to thesurface by touching them with a piece of clean filter paper.Select a location that is free of air currents. Place the cylinderver
20、tically in the water bath and let the temperature of thesample reach the test temperature as follows: Stir the contentsof the cylinder, being careful to avoid formation of air bubbles.When the temperature of the sample is 0.5C below the testtemperature, slowly and carefully lower the hydrometer into
21、the sample to a level two smallest scale divisions below that atwhich it will float, and then release the hydrometer.After it hascome to rest and floats freely away from the walls of thecylinder, read the gravity as the point at which the surface ofthe sample apparently cuts the hydrometer scale.7.2
22、 When the sample is at the test temperature, make thisobservation by placing the eye slightly below the level of theliquid and slowly raise the eye until the surface of the samplefirst seen as a distorted ellipse seems to become a straight linecutting the hydrometer scale. Determine the temperature
23、of thesample just before and also, for referee tests, just after readingthe hydrometer.METHOD BSPECIFIC GRAVITY OR DENSITY BYMEANS OF A PYCNOMETER8. Apparatus8.1 Pycnometer, 25-mL capacity with a ground-glass stop-per having a capillary opening, a chamber to provide forexpansion up to room temperatu
24、re, and a cap to preventevaporation.8.2 Water Bath, capable of maintaining the temperature 60.5C during the test.8.3 Thermometer An ASTM Low Softening Point Ther-mometer having a range from 2 to + 80C and conforming tothe requirements for Thermometer 15C as prescribed in Speci-fication E1.8.4 Analyt
25、ical Balance, having a sensitivity of 60.1 mg.9. ProcedureSpecific Gravity9.1 Clean the pycnometer by filling it with a saturatedsolution of chromic acid in concentrated sulfuric acid allowingit to stand for a few hours, emptying, and rinsing well withdistilled or deionized water.9.2 Fill the pycnom
26、eter with freshly boiled distilled ordeionized water that has been cooled to 2 or 3C below the testtemperature. Place it in the water bath maintained at the testtemperature until the pycnometer and its contents are at aconstant volume.9.3 After immersion in the bath for at least 30 min, adjustthe le
27、vel of liquid to the proper point on the pycnometer, putthe stopper in place, remove from the bath, wipe dry, andweigh. Care should be taken to avoid touching the pycnometerwith bare hands due to weight changes that will occur frompicking up moisture and oils. Record the weight as W1.9.4 Empty the p
28、ycnometer, rinse successively with alcoholor acetone, remove the vapor of the solvent by purging withclean, dry air or nitrogen, immerse in the bath, and bring to thetest temperature as was done before.After immersion at the testtemperature for at least 30 min, put the stopper in place,remove from t
29、he bath, wipe dry, and weigh. Record the weightas W2.9.5 Subtract the weight of the empty pychometer from theweight when filled with water in order to get the weight of thecontained water at the test temperature in air. The differenceW=W1W2.9.6 Cool the sample to 2 or 3C below the test temperature,f
30、ill the pycnometer with it, immerse in the bath, and bring tothe test temperature as was done before.After immersion at thetest temperature for at least 30 min, adjust the liquid level, putthe stopper in place, remove from the bath, wipe dry, andweigh. Record the temperature as S19.7 Subtract the we
31、ight of the empty pycnometer from theweight when filled with the sample in order to obtain theweight of the contained sample. The difference S=S1W2.10. Calculation10.1 Calculate the specific gravity (in air) as follows:Specific gravity T/T 5 S/W (3)where:T = test temperature10.2 Material specificati
32、ons often specify different tempera-tures at which specific gravity shall be measured. In order toconvert to any selected temperature, the coefficient of cubicalexpansion for the material being tested must be used. Inaddition, the absolute density of water at the desired tempera-ture is taken. The a
33、bsolute densities of water at differentD 2111 02 (2007)2temperatures are tabulated in various handbooks. In convertingto any desired temperature basis, the following equation isused:Specific gravity T3/T4C5 specific gravity T1/T21 1 kT3 T1!#dH2Oat T4dH2Oat T2(4)where:T1/T2= original temperature cond
34、itions,T3/T4= new temperature conditions,k = coefficient of cubical expansion (0.00117 at 0 to40C for trichloroethylene, 0.00102 at 0 to 25Cfor perchloroethylene, 0.00125 at 0 to 30C for1,1,1-trichloroethane, 0.00137 at 0 to 40C formethylene chloride, and 0.000927 at 0 to 30C forfluorocarbon-113), a
35、nddH2O= absolute density of water at the specified tempera-ture.10.2.1 ExampleAssume a specific gravity of 1.4550 at25/25C for trichloroethylene. This is to be converted to15/4C and 20/20C.Specific gravity 15/4C= 1.4550/1 + 0.00117(15 25) (0.999973/0.997044)= 1.4550/0.9883 1.00293= 1.4679where 0.999
36、973/0.997044 = ratio of the absolute density ofwater at 4C compared to the absolute density of water at 25C.Specific gravity 20/20C= 1.4550/1 + 0.00117 (2025) (0.998203/0.997044)= 1.4550/0.99415 1.00116= 1.4619where 0.998203/0.997044 = ratio of the absolute density ofwater at 20C compared to the abs
37、olute density of water at25C.NOTE 2Figures for absolute density of water are taken from theHandbook of Chemistry and Physics, Forty-ninth edition (19681969),published by The Chemical Rubber Co.11. ProcedureDensity11.1 Clean the pycnometer by filling it with a saturatedsolution of chromic acid in con
38、centrated sulfuric acid, allowingit to stand for a few hours, emptying, and rinsing well withdistilled water. Remove the water from the pycnometer byrinsing it with alcohol or acetone, and blow the vapor out withclean, dry air or nitrogen.11.2 Place the empty pycnometer in the water bath andbring it
39、 to the test temperature. Allow the pycnometer toremain at the test temperature for 30 min.11.3 Remove the pycnometer from the water bath, wipe itdry, put the stopper in place, and weigh the pycnometer.Record the weight as P. Do not touch the pycnometer with barehands, as moisture and oils from the
40、hands can affect theweight.11.4 Fill the pycnometer with the sample that has beencooled to 2 or 3C below the test temperature. Place it in thewater bath maintained at the test temperature 60.5C until thepycnometer and its contents are at a constant volume.11.5 After immersion in the bath for at leas
41、t 30 min, adjustthe level of liquid to the proper point on the pycnometer, putthe stopper in place, remove the pycnometer from the bath,wipe it dry, and weigh it. Record the weight as S.12. Calculation12.1 Calculate the density by the formula:d 5S 2 PV(5)whereP = is the weight of pycnometer,S = is t
42、he weight of the filled pycnometer, andV = is the volume (25 mL in this case) of the pycnometer.13. Precision and Bias13.1 When Test Method B is employed, different laborato-ries using different instruments should be able to obtain resultsthat differ from the means by not more than 0.0002.13.2 The l
43、imits of precision and bias of any method fordetermining specific gravity depend upon the attention that isgiven to details of calibration and technique. Consideration, ingeneral, must be given to the problems of keeping a largevolume of liquid (sometimes unstirred) at a constant tempera-ture, provi
44、ding for the effects of humidity or static electricityduring weighing of pycnometers, and weighing relatively largeloads.METHOD CSPECIFIC GRAVITY AND DENSITY BYMEANS OF AN ELECTRONIC DENSITOMETER14. Apparatus14.1 Electronic Densitometer, capable of measuring anddisplaying results to the fourth decim
45、al place. These analyzersconsist of a U-shaped, oscillating sample tube and a system forelectronic excitation, frequency counting, and display. Thedensity of the sample changes the mass of the tube, whichchanges the frequency of oscillation. The instrument must havemeans of maintaining the temperatu
46、re of the sample tube to60.05C in the desired range.14.2 Syringe or other device suitable for introduction of asample into the densitometer. Refer to the manufacturersinstructions.14.3 Thermometer, calibrated and graduated to 0.1C forobserving and setting the temperature of measurement. Thedensitome
47、ter may display sample temperature, in which casethe thermometer is not used.15. Calibration15.1 The densitometer must be calibrated for use at a giventemperature. Follow the manufacturers instructions for cali-bration. A densitometer is generally calibrated by setting theinstruments output (display
48、) at the density of dry air (0.0012at 60F, 20C, and 25C) when the measuring cell is empty,and then similarly setting the output at the density or specificgravity (1.0000) of water at the set temperature when the cellis full of degassed, deionized water (see 15.2 or 15.3).15.2 Calibration for Specifi
49、c GravityFill the measuringcell with degassed, deionized water and allow the cell andwater to come to the set temperature as shown by a constantoutput reading. This will take approximately 2 min. FollowingD 2111 02 (2007)3the manufacturers instructions, set the output to 1.0000. Theinstrument is now calibrated for specific gravity.15.3 Calibration for DensityFill the measuring cell withdegassed, deionized water and allow the cell and water to cometo the set temperature as shown by a constant output
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