Chemical Engineering / Kimya Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/14
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Article Citation - WoS: 6Citation - Scopus: 9The Effect of Military Conflict Zone in the Middle East on Atmospheric Persistent Organic Pollutant Contamination in Its North(Elsevier, 2023) Ayrı, İlknur; Genişoğlu, Mesut; Sofuoğlu, Aysun; Kurt Karakuş, Perihan B.; Birgül, Askın; Sofuoğlu, Sait CemilThis study aimed to investigate long-range atmospheric transport of selected POPs released due to the effects of mili-tary conflicts in regions to the south of Turkey's borders. Ten locations were selected to deploy passive air samplers at varying distances to the border on a southeast-west transect of the country, proximity-grouped as close, middle, and far. Sampling campaign included winter and transition months when desert dust transport events occur. Hypothesis of the study was that a decreasing trend would be observed with increasing distance to the border. Group comparisons based on statistical testing showed that PBDE-183, E45PCB, and dieldrin in winter; PBDE-28, PBDE-99, PBDE-154, p,p '-DDE, E14PBDE, and E25OCP in the transition period; and PBDE-28, PBDE-85, PBDE-99, PBDE-154, PBDE-190, PCB-52, E45PCB, p,p '-DDE, and E25OCP over the whole campaign had a decreasing trend on the transect. An analysis of concen-tration ratio to the background showed that long-range atmospheric transport impacted the study sites, especially those of close group in comparison to the local sources. Back-trajectory analyses indicated that there was transport from the conflict areas to sites in the close-proximity group, while farther sampling locations mostly received air masses from Europe, Russia, and former Soviet Union countries, followed by North Africa, rather than the military con-flict areas. In consequence, decrease in concentrations with distance and its relation to molecular weight through pro-portions, diagnostic ratios, analysis of concentration ratio to the background, and back-trajectory analyses support the effect of transport from the military-conflict area to its north.Article Citation - WoS: 21Citation - Scopus: 24Phytoremediation of Olive Mill Wastewater With Vetiveria Zizanioides (l.) Nash and Cyperus Alternifolius L.(Elsevier, 2021) Gören, Ayşegül Yağmur; Yücel, Arzu; Sofuoğlu, Sait Cemil; Sofuoğlu, AysunOlive Mill Wastewater (OMW) contains high concentrations of contaminants, including organic, nitrogen, and phenolic compounds that are extremely harmful to the environment and human health. The key purpose of this study was to remove total organic carbon (TOC), total nitrogen (TN), and phenolic compounds (TP) from OMW using floating wetland planted with Vetiveria zizanioides (L.) Nash (vetiver) and Cyperus alternifolius L. (umbrella palm) species. A total of eighteen floating wetlands were constructed. Twelve tanks were planted with vetiver and umbrella palm while another six tanks were maintained as unplanted controls. Experiments were conducted with wastewater volume of 56 L for 67 days using 5% (OMW-5) and 15% (OMW-15) treatments of OMW in a greenhouse. The highest TOC, TN, and TP removal efficiencies were found to be 95.3 ± 0.01, 82.7 ± 2.55, and 98.8 ± 0.07% in umbrella palm planted OMW-5, while the removal efficiencies were 84.9 ± 0.38, 92.7 ± 0.37, and 38.9 ± 1.97% in vetiver planted OMW-5. Similarly, the TOC, TN, and TP removal efficiencies in OMW-15 were 89.3 ± 0.28, 40.86 ± 1.73, and 96.8 ± 0.18% with umbrella palm and 89.1 ± 0.70, 23.7 ± 1.27, and 92.1 ± 0.41% with vetiver. The plants accumulated trace elements, especially in the roots, with the order of Fe > Mn > Cu > Zn > B > Pb > Cr > Ni > Co > Cd for umbrella palm. The umbrella palm shoot phenol content was found to be 2358 ± 201 and 1421 ± 198 mg/kg in OMW-5 and OMW-15, respectively. Overall, this study revealed that floating wetlands planted with vetiver and umbrella palm species have the potential to be used as a green treatment method to treat diluted high strength OMW.Article Citation - WoS: 12Citation - Scopus: 13Selected Persistent Organic Pollutants in Ambient Air in Turkey: Regional Sources and Controlling Factors(American Chemical Society, 2021) Güngörmüş, Elif; Sofuoğlu, Aysun; Çelik, Halil; Gedik, Kadir; Mulder, Marie D.; Lammel, Gerhard; Sofuoğlu, Sait CemilAs a result of its unique location, Turkey receives air masses from Europe, Russia, Middle East, and Africa, making it an important place in terms of long-range atmospheric transport (LRT) of contaminants. Atmospheric levels of 22 organochlorine pesticides (OCPs), 45 polychlorinated biphenyls (PCBs), and 14 polybrominated diphenyl ethers (PBDEs) were measured in two metropolitan cities, Istanbul and Izmir, on a weekly basis from May 2014 to May 2015. Dichlorodiphenyltrichloroethane (DDT) and its derivatives were dominant OCP species, followed by isomers of hexachlorocyclohexane (HCH) at both sites. The annual mean concentration of Sigma DDX (sum of o,p'-DDT, p,p'-DDT, o,p'-DDD, p,p'-DDD, o,p'-DDE, and p,p'-DDE) was 82 pg/m(3) for Istanbul and 89 pg/m(3) for Izmir, while these levels were about 46 pg/m(3) for Sigma HCHs (sum of alpha-, beta-, gamma-, and delta-HCH) at both of the sites. At both stations, tri- and tetra-PCBs and tetra- and penta-PBDEs were dominant congeners. The temperature dependence indicates that both LRT and local contaminated areas contribute to the elevated levels. A Lagrangian particle dispersion model (FLEXPART) showed a few potential source regions in northern Africa and Middle East, southern-southwestern and eastern Europe including Russia, as well as from local domestic metropolitan areas.Article Citation - WoS: 20Citation - Scopus: 25Indoor Air Partitioning of Synthetic Musk Compounds: Gas, Particulate Matter, House Dust, and Window Film(Elsevier, 2020) Balcı, Esin; Genişoğlu, Mesut; Sofuoğlu, Sait Cemil; Sofuoğlu, AysunDue to diversity of contaminants indoors and complexity in the physical structure of particulate matter, partition process of chemicals affects indoor concentration distribution. Synthetic Musk Compounds (SMCs) are ubiquitously found in household and personal care products, thus, in the environment. Exposure to SMCs is important for human health, therefore, their partitioning in indoor environmental media is a key issue. In this study, gas particle, house dust, andwindowfilm partitioning of SMCs were investigated in an indoor micro-environment. In a sealed and unoccupied room, a polycyclic and nitro musk mixture was left for volatilization for an hour. Then, samples were collected using XAD-2 sandwiched between two PUF plugs, glass-fiber filter, and wipes for gas, PM10, window-film, house dust phases, respectively, for 145 h. Collected samples were analyzed using a GC-MS. Results demonstrated that MC concentrations decreased over time, non-linearly. Six of the SMCs partitioned to PM10 with at least 10% at beginning of the experiment, whereas the number of compounds dropped to two at the end, showing that SMCs may partition well between the two phases but they tend to be in the gas phase. They were also detected in the film and dust phases but a decrease pattern similar to gas-particle was not observed. Spearman correlations indicate that the dust and film-associated concentrations were governed by similar processes but PM-associated concentrations were not. SMCs may be found in all phases, mainly in house dust in terms of mass among the studied media and unaccounted surface reservoirs. Therefore, their partitioning between indoor media has key implications for human exposure. (C)20 Elsevier B.V. All rights reserved.Article Citation - WoS: 15Citation - Scopus: 19Brominated Flame Retardants in a Computer Technical Service: Indoor Air Gas Phase, Submicron (pm1) and Coarse (pm10) Particles, Associated Inhalation Exposure, and Settled Dust(Elsevier Ltd., 2019) Genişoğlu, Mesut; Sofuoğlu, Aysun; Kurt Karakuş, Perihan Binnur; Birgül, Aşkın; Sofuoğlu, Sait CemilBrominated flame retardants (BFRs) are found in multi-media indoors, therefore, may pose serious risks to human health. This study investigated the occurrence of BFRs in particulate matter (PM1 and PM10) and gas phase by active and passive sampling, and settled dust to estimate potential exposure in a computer technical service. Polybrominated diphenyl ethers (PBDEs) and their alternatives (novel BFRs, NBFRs) were studied. PM and gas phase were collected on glass fiber filters and polyurethane foam plugs, respectively, and analyzed with a GC/MS after extraction, clean-up, and concentration. Inhalation exposure of the staff was estimated based on the measured concentrations using Monte Carlo simulation. BDE-209 was the dominating PBDE congener in all media while bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate and 1,2-bis(2,4,6-tribromophenoxy)ethane were those of NBFRs. Submicron particulate matter (PM1) BFR levels constituted about one half of the PM10-associated concentrations, while average PM10 mass concentration (69.9 μg m−3) was nine times that of PM1 (7.73 μg m−3). Calculated log10 dust-gas and PM-gas partitioning coefficients ranged from −5.03 to −2.10, −2.21 to −0.55, and −2.26 to −1.04 for settled dust, PM10, and PM1, respectively. The indoor/outdoor concentration ratios were >1 for all compounds indicating the strength of indoor sources in the service. The estimated potential inhalation exposures, for future chronic-toxic and carcinogenic risk assessments, indicated that the levels of gas-phase and PM1-associated exposures were similar at approximately one half of PM10-associated levels. Results of this study indicate that the occurrence of BFRs in all studied media should be taken into consideration for occupational health mitigation efforts.Article Citation - WoS: 27Citation - Scopus: 28Fast Formation of Nitro-Pahs in the Marine Atmosphere Constrained in a Regional-Scale Lagrangian Field Experiment(American Chemical Society, 2019) Mulder, Marie D.; Dumanoğlu, Yetkin; Efstathiou, Christos; Kukucka, Petr; Matejovicova, Jana; Maurer, Christian; Pribylova, Petra; Prokes, Roman; Sofuoğlu, Aysun; Sofuoğlu, Sait Cemil; Wilson, Jake; Zetzsch, Cornelius; Wotawa, Gerhard; Lammel, GerhardPolycyclic aromatic hydrocarbons (PAHs) and some of their nitrated derivatives, NPAHs, are seemingly ubiquitous in the atmospheric environment. Atmospheric lifetimes may nevertheless vary within a wide range, and be as short as a few hours. The sources and sinks of NPAH in the atmosphere are not well understood. With a Lagrangian field experiment and modeling, we studied the conversion of the semivolatile PAHs fluoranthene and pyrene into the 2-nitro derivatives 2-nitrofluoranthene and 2-nitropyrene in a cloud-free marine atmosphere on the time scale of hours to 1 day between a coastal and an island site. Chemistry and transport during several episodes was simulated by a Lagrangian box model i.e., a box model coupled to a Lagrangian particle dispersion model, FLEXPART-WRF. It is found that the chemical kinetic data do capture photochemical degradation of the 4-ring PAHs under ambient conditions on the time scale of hours to 1 day, while the production of the corresponding NPAH, which sustained 2-nitrofluoranthene/fluoranthene and 2-nitropyrene/pyrene yields of (3.7 ± 0.2) and (1.5 ± 0.1)%, respectively, is by far underestimated. Predicted levels of NPAH come close to observed ones, when kinetic data describing the reactivity of the OH-adduct were explored by means of theoretically based estimates. Predictions are also underestimated by 1-2 orders of magnitude, when NPAH/PAH yields reported from laboratory experiments conducted under high NOx conditions are adopted for the simulations. It is concluded that NPAH sources effective under low NOx conditions, are largely underestimated.Article Citation - WoS: 91Citation - Scopus: 95Source Apportionment and Carcinogenic Risk Assessment of Passive Air Sampler-Derived Pahs and Pcbs in a Heavily Industrialized Region(Elsevier Ltd., 2018) Çetin, Banu; Yurdakul, Sema; Güngörmüş, Elif; Öztürk, Fatma; Sofuoğlu, Sait CemilCancer has become the primary reason of deaths in Dilovasi probably due to its location with unique topography under the influence of heavy industrialization and traffic. In this study, possible sources and carcinogenic health risks of PAHs and PCBs were investigated in Dilovasi region by Positive Matrix Factorization (PMF) and the USEPA approach, respectively. PAHs and PCBs were measured monthly for a whole year at 23 sampling sites using PUF disk passive samplers. Average ambient air concentrations were found as 285 ± 431 ng/m 3 and 4152 ± 6072 pg/m 3 , for Σ 15 PAH and Σ 41 PCB, respectively. PAH concentrations increased with decreasing temperature especially at urban sites, indicating the impact of residential heating in addition to industrial activities and traffic. On the other hand, PCB concentrations mostly increased with temperature probably due to enhanced volatilization from their sources. Possible sources of PAHs were found as emissions of diesel and gasoline vehicles, biomass and coal combustion, iron and steel industry, and unburned petroleum/petroleum products, whereas iron-steel production, coal and biomass burning, technical PCB mixtures, and industrial emissions were identified for PCBs. The mean carcinogenic risk associated with inhalation exposure to PAHs and PCBs were estimated to be >10 −6 and >10 −5 , respectively, at all sampling points, while the 95th percentile was >10 −5 at 15 of 23 and >10 −4 at 8 of 23 sampling locations, respectively. Probabilistic assessment showed, especially for PCBs, that a majority of Dilovasi population face significant health risks. The higher risks due to PCBs further indicated that PCBs and possibly other pollutants originating from the same sources such as PBDEs and PCNs may be an important issue for the region.Article Citation - WoS: 32Citation - Scopus: 37Mcdm Analysis of Wind Energy in Turkey: Decision Making Based on Environmental Impact(Springer Verlag, 2018) Değirmenci, Sinem; Bingöl, Ferhat; Sofuoğlu, Sait CemilDevelopment of new wind energy projects require complex planning process involving many social, technical, economic, environmental, political concerns, and different agents such as investors, utilities, governmental agencies, or social groups. The aim of this study is to develop a tool combining Geographic Information System (GIS) and Multi-Criteria Decision-Making (MCDM) methodologies, and its application for Turkey as a case study. A variety of constraints and criteria were identified based on a literature review and regulations gathered from variety of agencies, use of which resulted in determination of infeasible sites. Then, pairwise comparisons were carried out using analytic hierarchy process as the MCDM method to estimate relative importance of the criteria, and to visualize a suitability map with three classes. As the final stage, decision making was carried out based on environmental impact where 45.5% of the Turkish territory was found as infeasible area. Sixty percent of the remaining area are covered by the moderate suitability class, followed by the highly suitable area (20.3%) and low suitable area (19.8%). The output of this study can be used by energy planners to estimate the extent that wind energy can be developed based on public perception, administrative, and environmental aspectsArticle Citation - WoS: 18Citation - Scopus: 21Polybrominated Diphenyl Ethers (pbdes) in Background Air Around the Aegean: Implications for Phase Partitioning and Size Distribution(Springer Verlag, 2017) Besis, Athanasios; Lammel, Gerhard; Kukucka, Petr; Samara, Constantini; Sofuoğlu, Aysun; Dumanoğlu, Yetkin; Eleftheriadis, Kostas; Kouvarakis, Giorgos; Sofuoğlu, Sait Cemil; Vassilatou, Vassiliki; Voutsa, DimitraThe occurrence and atmospheric behavior of tri- to deca-polybrominated diphenyl ethers (PBDEs) were investigated during a 2-week campaign concurrently conducted in July 2012 at four background sites around the Aegean Sea. The study focused on the gas/particle (G/P) partitioning at three sites (Ag. Paraskevi/central Greece/suburban, Finokalia/southern Greece/remote coastal, and Urla/Turkey/rural coastal) and on the size distribution at two sites (Neochorouda/northern Greece/rural inland and Finokalia/southern Greece/remote coastal). The lowest mean total (G + P) concentrations of ∑7PBDE (BDE-28, BDE-47, BDE-66, BDE-99, BDE-100, BDE-153, BDE-154) and BDE-209 (0.81 and 0.95 pg m−3, respectively) were found at the remote site Finokalia. Partitioning coefficients, KP, were calculated, and their linear relationships with ambient temperature and the physicochemical properties of the analyzed PBDE congeners, i.e., the subcooled liquid pressure (PL°) and the octanol-air partition coefficient (KOA), were investigated. The equilibrium adsorption (PL°-based) and absorption (KOA-based) models, as well as a steady-state absorption model including an equilibrium and a non-equilibrium term, both being functions of log KOA, were used to predict the fraction Φ of PBDEs associated with the particle phase. The steady-state model proved to be superior to predict G/P partitioning of BDE-209. The distribution of particle-bound PBDEs across size fractions < 0.95, 0.95–1.5, 1.5–3.0, 3.0–7.2, and > 7.2 μm indicated a positive correlation between the mass median aerodynamic diameter and log PL° for the less brominated congeners, whereas a negative correlation was observed for the high brominated congeners. The potential source regions of PBDEs were acknowledged as a combination of long-range transport with short-distance sources.Article Citation - WoS: 108Citation - Scopus: 113Spatial and Seasonal Variations, Sources, Air-Soil Exchange, and Carcinogenic Risk Assessment for Pahs and Pcbs in Air and Soil of Kutahya, Turkey, the Province of Thermal Power Plants(Elsevier Ltd., 2017) Dumanoğlu, Yetkin; Gaga, Eftade O.; Güngörmüş, Elif; Sofuoğlu, Sait Cemil; Odabaşı, MustafaAtmospheric and concurrent soil samples were collected during winter and summer of 2014 at 41 sites in Kutahya, Turkey to investigate spatial and seasonal variations, sources, air-soil exchange, and associated carcinogenic risks of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). The highest atmospheric and soil concentrations were observed near power plants and residential areas, and the wintertime concentrations were generally higher than ones measured in summer. Spatial distribution of measured ambient concentrations and results of the factor analysis showed that the major contributing PAH sources in Kutahya region were the coal combustion for power generation and residential heating (48.9%), and diesel and gasoline exhaust emissions (47.3%) while the major PCB sources were the coal (thermal power plants and residential heating) and wood combustion (residential heating) (45.4%), and evaporative emissions from previously used technical PCB mixtures (34.7%). Results of fugacity fraction calculations indicated that the soil and atmosphere were not in equilibrium for most of the PAHs (88.0% in winter, 87.4% in summer) and PCBs (76.8% in winter, 83.8% in summer). For PAHs, deposition to the soil was the dominant mechanism in winter while in summer volatilization was equally important. For PCBs, volatilization dominated in summer while deposition was higher in winter. Cancer risks associated with inhalation and accidental soil ingestion of soil were also estimated. Generally, the estimated carcinogenic risks were below the acceptable risk level of 10− 6. The percentage of the population exceeding the acceptable risk level ranged from < 1% to 16%, except, 32% of the inhalation risk levels due to PAH exposure in winter at urban/industrial sites were > 10− 6.
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