Estimation of polychlorinated biphenyl fugacity ratios.
On the quantitative comparison of solubilities or vapor pressures of homologous series, the variation in the effect of crystal structure on solid properties may substantially influence the outcome of the comparison. Usually, the effect of this variation is eliminated by comparing values of the liquid state. The ratio of solid to liquid properties is called the fugacity ratio. Fugacity ratios are usually calculated from fusion thermodynamic data. For 41 polychlorinated biphenyls (PCBs), fusion enthalpy was found to be correlated with fusion entropy. Highly linear correlations were observed for non-ortho-PCBs, mono-ortho-PCBs, and diortho-PCBs. Fugacity ratios estimated from the fusion enthalpy-entropy linear regression parameters were equal, within 10% on average, to fugacity ratios calculated from fusion enthalpy for ortho chlorinated PCBs with melting points below 380 K and for non-ortho-PCBs. For ortho chlorinated PCBs with melting points above 380 K, fugacity ratios were better estimated from a nonlinear regression of fugacity ratios against the melting point and the system temperature. For all 209 PCB congeners, fugacity ratios at 298 K are listed on the basis of experimental fusion data or estimates from the regressions.
Van Noort
Paul C M
PC
Institute for Inland Water Management and Wastewater Treatment, P.O. Box 17, 8200 AA Lelystad, The Netherlands. p.vnoort@riza.rws.minvenw.nl
D000465:Algorithms; D019277:Entropy; D004785:Environmental Pollutants / Q000737:chemistry*; D044367:Phase Transition; D011078:Polychlorinated Biphenyls / Q000737:chemistry*; D044366:Transition Temperature
D004785:Environmental Pollutants; D011078:Polychlorinated Biphenyls