ASTM E2071-2000(2015) Standard Practice for Calculating Heat of Vaporization or Sublimation from Vapor Pressure Data《采用蒸气压力数据计算汽化热或蒸馏热的标准实践规程》.pdf
《ASTM E2071-2000(2015) Standard Practice for Calculating Heat of Vaporization or Sublimation from Vapor Pressure Data《采用蒸气压力数据计算汽化热或蒸馏热的标准实践规程》.pdf》由会员分享,可在线阅读,更多相关《ASTM E2071-2000(2015) Standard Practice for Calculating Heat of Vaporization or Sublimation from Vapor Pressure Data《采用蒸气压力数据计算汽化热或蒸馏热的标准实践规程》.pdf(4页珍藏版)》请在麦多课文档分享上搜索。
1、Designation: E2071 00 (Reapproved 2015)Standard Practice forCalculating Heat of Vaporization or Sublimation from VaporPressure Data1This standard is issued under the fixed designation E2071; the number immediately following the designation indicates the year oforiginal adoption or, in the case of re
2、vision, 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 practice describes the calculation of the heat ofvaporization of a liquid or the heat of subl
3、imation of a solidfrom measured vapor pressure data. It is applicable to pureliquids, azeotropes, pure solids, and homogenous solid solu-tions over the temperature range for which the vapor pressureequation fitted to the measured data is applicable.NOTE 1This practice is generally not applicable to
4、liquid mixtures.For a pure liquid or azeotrope, composition does not change uponvaporization so that the integral heat of vaporization is identical to thedifferential heat of vaporization. Non-azeotropic liquid mixtures changecomposition upon vaporizing. Heat of vaporization data computed fromthis p
5、ractice for a liquid mixture are valid only as an approximation to themixture differential heat of vaporization; it is not a valid approximation tothe mixture integral heat of vaporization.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in
6、thisstandard.1.3 There is no ISO standard equivalent to this practice.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
7、 applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D2879 Test Method for Vapor Pressure-Temperature Rela-tionship and Initial Decomposition Temperature of Liq-uids by IsoteniscopeE1142 Terminology Relating to Thermophysical PropertiesE1194 Test Method f
8、or Vapor Pressure (Withdrawn 2013)3E1719 Test Method for Vapor Pressure of Liquids by Ebul-liometryE1782 Test Method for Determining Vapor Pressure byThermal Analysis3. Terminology3.1 Symbols:3.1.1 A, B, CAntoine vapor pressure equation constants(log10, kPa, K), Antoine vapor pressure equation:log10
9、P 5 A 2 B/T1C!3.1.2 Pvapor pressure, kPa.3.1.3 Pccritical pressure, kPa.3.1.4 Prreduced pressure = P/Pc.3.1.5 Tabsolute temperature, K.3.1.6 Tccritical temperature, K.3.1.7 Trreduced temperature = T/Tc.3.1.8 Vmolar volume, cm3/mol.3.1.9 Rgas constant, 8.31433 J/mol-K; 8314330 kPa-cm3/mol-K.3.1.10 HV
10、heat of vaporization, J/mol.3.1.11 ZVdifference in compressibility factor (Z = PV/RT) upon vaporization. Clapeyron equation:HV52RZVdlnP!/d1/T!#3.1.11.1 DiscussionThe subscript “V” will be usedthroughout this practice to designate the vaporization of aliquid. If the vapor pressure data were measured
11、for a solid,substitute the subscript “S” for the sublimation of a solid.3.2 Definitions:3.2.1 Specialized terms used in this practice are defined inTerminology E1142.3.2.2 sublimationtransition from a solid phase to a gas-eous phase.3.2.3 vaporizationtransition from a liquid phase to agaseous phase.
12、1This practice is under the jurisdiction of Committee E37 on Thermal Measure-ments and is the direct responsibility of Subcommittee E37.10 on Fundamental,Statistical and Mechanical Properties.Current edition approved May 1, 2015. Published May 2015. Originallyapproved in 2000. Last previous edition
13、approved in 2010 as E2071 00 (2010).DOI: 510.1520/E2071-00R15.2For 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
14、.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 States14. Summary of Practice4.1 Vapor pressure data are measured by other referencedASTM standards and then
15、 correlated with the Antoine equa-tion. The heat of vaporization or sublimation is computed at thedesired temperature from the vapor-pressure temperature de-rivative from the fitted Antoine equation by use of theClapeyron equation (1).4In the Clapeyron equation, ZVisdetermined by either the Clausius
16、-Clapeyron(2) approxima-tion:ZV5 1!or the Haggenmacher (3) approximation:SZV5$1 2Pr/Tr!3#%12D4.2 An example calculation is given in Annex A1.5. Significance and Use5.1 If the heat of vaporization or sublimation is absorbed orliberated in a process at constant pressure, it is called enthalpyof vapori
17、zation or sublimation. Enthalpy of vaporization orsublimation is a fundamental thermodynamic property of aliquid or solid. It is an important quantity in the design of heatexchangers and other chemical process units. Enthalpy ofvaporization is also used to calculate solubility parameters (4).5.2 Thi
18、s practice may be used in research, regulatorycompliance, and quality assurance applications.6. Experimental Vapor Pressure Data6.1 Vapor pressure data are measured by Test MethodsD2879, E1194, E1719,orE1782. Note the safety precautionscontained in the test method used.6.1.1 Vapor pressure data from
19、 other reliable sources, forexample, peer-review technical journals, may be used. Thesource of the vapor pressure data must be noted.6.2 The measured vapor pressure data are fitted to anAntoine vapor pressure equation. See 10.3 in Test MethodE1719 for details on least-squares regression of vapor pre
20、ssuredata.7. Calculation7.1 At each temperature of interest, calculate the vaporpressure from the Antoine equation and calculate the vapor-pressure temperature derivative from the fitted Antoine equa-tion constants from:dlnP!/d1/T!# 522.3025851BT2/T1C!2#7.2 Calculate an approximation to ZVat each te
21、mperature.7.2.1 The Clausius-Clapeyron approximation to ZVis:ZV1.07.2.2 The Haggenmacher approximation to ZVis:ZV5$1 2Pr/Tr!3#%12NOTE 2The Clausius-Clapyeron approximation is generally used forsolids and for liquids at low Tr. The Haggenmacher approximation isgenerally used for liquids up to Tr 0.75
22、.7.2.3 If equation of state (Z) data are available for both thecondensed and gaseous phases, ZVmay be calculated directlyfrom the equation of state data.7.3 Calculate the heat of vaporization or heat of sublimationat each temperature from the Clapeyron equation:HV52RZVdlnP!/d1/T!#8. Report8.1 Report
- 1.请仔细阅读文档,确保文档完整性,对于不预览、不比对内容而直接下载带来的问题本站不予受理。
- 2.下载的文档,不会出现我们的网址水印。
- 3、该文档所得收入(下载+内容+预览)归上传者、原创作者;如果您是本文档原作者,请点此认领!既往收益都归您。
下载文档到电脑,查找使用更方便
5000 积分 0人已下载
下载 | 加入VIP,交流精品资源 |
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- ASTME207120002015STANDARDPRACTICEFORCALCULATINGHEATOFVAPORIZATIONORSUBLIMATIONFROMVAPORPRESSUREDATA 采用

链接地址:http://www.mydoc123.com/p-530208.html