Comparison of methods employing gas chromatography retention data to determine vapour pressures at 298 K

Abstract

Validity of five models suggested for expressing the relationship between vapour pressures and GC retention times measured on a non-polar capillary column were tested on a common set of compounds [five homologous series of the type H–(CH 2) n –Y, where Y denotes Cl, Br, CHO, OCOCH 3 and COOCH 3, and n varies from 6 to 14]. Standard methods of statistical analysis, as well as vapour pressure values obtained independently from direct vapour pressure measurements were used as validity criteria. For the 40-compound data set examined, the methods provided vapour pressures agreeing within 9.2–24.7% (average absolute percent error) with direct experimental data.