1、Designation:D342993(Reapproved 2012)Standard Test Method forSolubility of Fixed Gases in Low-Boiling Liquids1This standard is issued under the fixed designation D3429;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last r
2、evision.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 the solu-bilities of nonreactive gases such as nitrogen and helium inliquids that bo
3、il below 273 K.This test method is applicable attemperatures from 77 to 300 K from subambient pressure to6.5 MPa(65 atm).This test method does not provide foranalysis of the vapor phase in equilibrium with the liquid(seeSection 3 for a description of terms).1.2 This test method as written describes
4、the procedures tobe followed for determination of the solubilities of helium andnitrogen.If suitable modifications are made to the analyticalmeasurements by gas chromatography,solubilities of othergases such as argon,hydrogen,oxygen,etc.,can be deter-mined.1.3 The values stated in SI units are to be
5、 regarded as thestandard.In cases where materials,products,or equipment areavailable in inch-pound units only,SI units are omitted.1.4 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
6、appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.For specific hazardstatements,see 6.1.2 and 7.1 and Annex A1.2.Referenced Documents2.1 ASTM Standards:2E260 Practice for Packed Column Gas Chromatography3.Terminology3.1 Definitions of Te
7、rms Specific to This Standard:3.1.1 carrier gas,ngas used to sweep samples through thegas chromatograph.3.1.2 elution,nthe process of removing a material ab-sorbed on the stationary phase of the gas chromatographcolumn by displacing it with the flowing carrier gas.3.1.3 fractionation,nchange of comp
8、osition caused bychange of pressure.3.1.4 liquid or test liquid,nsolvent for test gas.3.1.5 nonreactive gas,ngas that does not react chemicallywith the test liquid.3.1.6 test gas,ngas whose solubility is being determined.3.1.7 vapor,nvapor phase of test liquid.4.Summary of Test Method4.1 A sample of
9、 test liquid A is saturated with test gas B atspecified temperature and pressure.A portion of the solution iswithdrawn and vaporized in an evacuated sample container atroom temperature.The concentration of gas B in the vaporizedsample is determined by gas chromatography.It is necessarythat the molar
10、 concentration of the gas in the sample containerbe the same as in the liquid phase.This will be true iffractionation of the sample is avoided while withdrawing itfrom the liquid phase,if no decomposition or polymerizationof the test liquid occurs on vaporization,and if the vapor of thetest liquid d
11、oes not react with the walls of the sample containeror connecting lines.It is also necessary that both the test gasand the vapor of the test liquid behave nearly ideally at 101 kPa(1 atm).If the above requirements are met,this test method willgive estimates of solubility with an accuracy of 62%.5.Si
12、gnificance and Use5.1 The solubility of fixed gases in liquids is an importantengineering parameter in the design of hydraulic systems.It isa measure of the amount of gas that can be released fromsolution when a system undergoes changes in pressure andtemperature.Theoretical considerations permit ap
13、proximatevalues of gas solubility to be computed with reasonableaccuracy.Dissolved gases are separated and quantified chro-matographically.The test method is restricted to use withlow-boiling liquid samples.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid
14、 Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.L0.07 on Engineering Sciences of High Performance Fluids andSolids(Formally D02.1100).Current edition approved April 15,2012.Published April 2012.Originallyapproved in 1975.Last previous edition approved in 2007 as D342993(200
15、7).DOI:10.1520/D3429-93R12.2For referenced ASTM standards,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 H
16、arbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.Apparatus6.1 Saturator and Sampler System,suitable for the tests oflow-boiling liquids and gases at various pressures andtemperatures,shown schematically in Fig.1.The systemcomprises four parts:6.1.1 High-Pressure Test Chamber,with internal capacity ofapproximately(1 L)such as shown in Fig.2.The lid of the testchamber is equipped with three ports.The first is to contain athermocouple well,the second is for the addition of t
