Sürdürülebilir Yeşil Kampüs Koleksiyonu / Sustainable Green Campus Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7755
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Article Citation - WoS: 24Citation - Scopus: 25Atmospheric Concentrations and Phase Partitioning of Polycyclic Aromatic Hydrocarbons in Izmir, Turkey(John Wiley and Sons Inc., 2011) Demircioğlu, Eylem; Sofuoğlu, Aysun; Odabaşı, MustafaAmbient air polycyclic aromatic hydrocarbon (PAH) samples were collected at a suburban (n=63) and at an urban site (n=14) in Izmir, Turkey. Average gas-phase total PAH (∑ 14PAH) concentrations were 23.5ngm -3 for suburban and 109.7ngm -3 for urban sites while average particle-phase total PAH concentrations were 12.3 and 34.5ngm -3 for suburban and urban sites, respectively. Higher ambient PAH concentrations were measured in the gas-phase and ∑ 14PAH concentrations were dominated by lower molecular weight PAHs. Multiple linear regression analysis indicated that the meteorological parameters were effective on ambient PAH concentrations. Emission sources of particle-phase PAHs were investigated using a diagnostic plot of fluorene (FLN)/(fluorine+pyrene; PY) versus indeno[1,2,3-cd]PY/(indeno[1,2,3-cd]PY+benzo[g,h,i]perylene) and several diagnostic ratios. These approaches have indicated that traffic emissions (petroleum combustion) were the dominant PAH sources at both sites for summer and winter seasons. Experimental gas-particle partition coefficients (K P) were compared to the predictions of octanol-air (K OA) and soot-air (K SA) partition coefficient models. The correlations between experimental and modeled K P values were significant (r 2=0.79 and 0.94 for suburban and urban sites, respectively, p<0.01). Octanol-based absorptive partitioning model predicted lower partition coefficients especially for relatively volatile PAHs. However, overall there was a relatively good agreement between the measured K P and soot-based model predictions. Ambient air polycyclic aromatic hydrocarbon (PAH) samples were collected at a suburban and at an urban site in Izmir, Turkey. The multiple linear regression analysis indicated that the meteorological parameters were effective on the measured ambient PAH concentrations. The results indicated that traffic emissions were the dominant PAH sources at both sites for summer and winter seasons.Article Citation - WoS: 21Citation - Scopus: 23Activated Carbon Adsorption of Fuel Oxygenates Mtbe and Etbe From Water(Springer Verlag, 2009) İnal, Fikret; Yetgin, Senem; Aksu, Gülsüm T.; Şimşek, Selvi; Sofuoğlu, Aysun; Sofuoğlu, Sait CemilThe aqueous phase adsorption of fuel oxygenates methyl tertiary butyl ether (MTBE) and ethyl tertiary butyl ether (ETBE) onto commercially available granular activated carbon (GAC; Norit GAC 1240) was investigated in a batch system at 27°C. The oxygenate concentrations were determined by headspace gas chromatography/mass spectrometry analyses. The experimental data were used with four two-parameter isotherm models (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich) and two kinetic models (pseudo first-order and pseudo second-order) to determine equilibrium and kinetic parameters. Considering the correlation coefficient and root mean square error, Dubinin-Radushkevich isotherm showed better fit with the equilibrium data for MTBE. However, the performances of Langmuir and Dubinin-Radushkevich models were comparable for ETBE. The adsorption capacities were calculated as 5.50 and 6.92 mg/g for MTBE and ETBE, respectively, at an equilibrium solution concentration of 1 mg/L using Dubinin-Radushkevich isotherm. The differences between the model predictions and experimental data were similar for the pseudo first-order and pseudo second-order kinetic models. Gibbs free-energy changes of adsorption were found to be -22.59 and -28.55 kJ/mol for MTBE-GAC and ETBE-GAC systems, respectively, under the experimental conditions studied.