ASTM_E_1719_-_12.pdf

Designation:E171912Standard Test Method forVapor Pressure of Liquids by Ebulliometry1This standard is issued under the fixed designation E1719;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.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 describes procedures for determinationof the vapor pressure of liquids by ebulliometry(boiling pointmeasurements).It is applicable to pure liquids and azeotropesthat have an atmospheric boiling point between 285 and 575 Kand that can be condensed completely and returned to theebulliometer boiler,that is,all materials must be condensableat total reflux.Liquid mixtures may be studied if they do notcontain non-condensable components.Liquid mixtures thatcontain trace amounts of volatile but completely condensablecomponents may also be studied,but they will produce vaporpressure data of greater uncertainty.Boiling point temperaturesare measured at applied pressures of 1.0 to 100 kPa(7.5 to 760torr).1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 There is no ISO equivalent to this standard.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 appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.For specific hazardstatements,see Section 8.2.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD2879 Test Method for Vapor Pressure-Temperature Rela-tionship and Initial Decomposition Temperature of Liq-uids by IsoteniscopeE1 Specification for ASTM Liquid-in-Glass ThermometersE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE1142 Terminology Relating to Thermophysical PropertiesE1194 Test Method for Vapor Pressure(Withdrawn 2013)3E1970 Practice for Statistical Treatment of ThermoanalyticalData3.Terminology3.1 Definitions:3.1.1 The following terms are applicable to this test methodand can be found in Terminology E1142;boiling temperatureand vapor pressure.3.1.2 For definitions of other terms used in this test methodrefer to Terminology E1142.3.2 Definitions of Terms Specific to This Standard:3.2.1 ebulliometera one-stage,total-reflux boiler designedto minimize superheating of the boiling liquid.3.2.2 manostata device for maintaining constant vacuumor pressure.3.2.3 superheatingthe act of heating a liquid above theequilibrium boiling temperature for a particular applied pres-sure.3.3 Symbols:A,B,C=Antoine vapor pressure equation constants(log10,kPa,K)for the Antoine vapor pressure equation:log10P=A B/(T+C).P=vapor pressure,kPa.T=absolute temperature,K.4.Summary of Test Method4.1 A specimen is charged to the ebulliometer boiler.Theebulliometer is connected to a manostat,and coolant iscirculated through the ebulliometer condenser.The manostat isset at a low pressure,and the specimen is heated to the boilingtemperature.The boiling temperature and manostat pressureare recorded upon reaching a steady-state,and the manostatpressure is raised to a higher value.A suitable number(usuallyfive or more)of boiling temperature points are recorded atsuccessively higher controlled pressures.The pressure-temperature data are fitted to the Antoine vapor pressure1This test method is under the jurisdiction ofASTM Committee E37 on ThermalMeasurements and is the direct responsibility of Subcommittee E37.01 on Calo-rimetry and Mass Loss.Current edition approved April 1,2012.Published July 2012.Originallyapproved in 1995.Last previous edition approved in 2005 as E1719 05.DOI:10.1520/E1719-12.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 equation.Vapor pressure values required for specific reportsare then computed from the derived equation.4.2 The capability of the entire apparatus(ebulliometer,thermometer,manostat,etc.)is checked periodically by theprocedure described in Annex A1.This procedure consists ofmeasuring the boiling temperature data for a pure referencesubstance such as water and comparing the derived vaporpressure data to the known reference values.5.Significance and Use5.1 Vapor pressure is a fundamental thermodynamic prop-erty of a liquid.Vapor pressure and boiling temperature dataare required for material safety data sheets(MSDS),theestimation of volatile organic compounds(VOC),and otherneeds related to