Chemical Engineering / Kimya Mühendisliği

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Subject: search.filters.subject.Octanol-air partition coefficient

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  • Article
    Citation - WoS: 33
    Citation - Scopus: 35
    Henry's Law Constant, Octanol-Air Partition Coefficient and Supercooled Liquid Vapor Pressure of Carbazole as a Function of Temperature: Application To Gas/Particle Partitioning in the Atmosphere
    (Elsevier Ltd., 2006) Odabaşı, Mustafa; Çetin, Banu; Sofuoğlu, Aysun
    The Henry's law constant for carbazole was experimentally determined between 5 and 35°C using a gas-stripping technique. The following equation was obtained for dimensionless Henry's law constant (H′) versus temperature (T, K):lnH′=-3982(T,K)-1+1.01 Temperature-dependent octanol-air partition coefficients (KOA) and supercooled liquid vapor pressures (PL, Pa) of carbazole were also determined using the GC retention time method. The temperature dependence of KOA and PL were explained by the following:logKOA=4076/(T,K)-5. 65logPL(Pa)=-3948(T,K)-1+11.84 The gas and particle-phase carbazole concentrations measured previously in Chicago, IL in 1995 was used for gas/particle partitioning modeling. Octanol based absorptive partitioning model consistently underpredicted the gas/particle partition coefficients (K p) for all sampling periods. However, overall there was a good agreement between the measured Kp and soot-based model predictions.
  • Article
    Citation - WoS: 220
    Citation - Scopus: 234
    Determination of Octanol-Air Partition Coefficients and Supercooled Liquid Vapor Pressures of Pahs as a Function of Temperature: Application To Gas-Particle Partitioning in an Urban Atmosphere
    (Elsevier Ltd., 2006) Odabaşı, Mustafa; Çetin, Eylem; Sofuoğlu, Aysun
    Octanol-air partition coefficients (KOA) for 14 polycyclic aromatic hydrocarbons (PAHs) were determined as a function of temperature using the gas chromatographic retention time method. log KOA values at 25° ranged over six orders of magnitude, between 6.34 (acenaphthylene) and 12.59 (dibenz[a,h]anthracene). The determined KOA values were within factor of 0.7 (dibenz[a,h]anthracene) to 15.1 (benz[a]anthracene) of values calculated as the ratio of octanol-water partition coefficient to dimensionless Henry's law constant. Supercooled liquid vapor pressures (PL) of 13 PAHs were also determined using the gas chromatographic retention time technique. Activity coefficients in octanol calculated using KOA and PL ranged between 3.2 and 6.2 indicating near-ideal solution behavior. Atmospheric concentrations measured in this study in Izmir, Turkey were used to investigate the partitioning of PAHs between particle and gas-phases. Experimental gas-particle partition coefficients (Kp) were compared to the predictions of KOA absorption and KSA (soot-air partition coefficient) models. Octanol-based absorptive partitioning model predicted lower partition coefficients especially for relatively volatile PAHs. Ratios of measured/modeled partition coefficients ranged between 1.1 and 15.5 (4.5±6.0, average±SD) for KOA model. KSA model predictions were relatively better and measured to modeled ratios ranged between 0.6 and 5.6 (2.3±2.7, average±SD).