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Öğe An investigation into the analytical methods for the determination of selected chlorinated phenols in aqueousphase(PARLAR SCIENTIFIC PUBLICATIONS (P S P), 2004) Tor, A; Cengeloglu, Y; Aydin, ME; Wichmann, H; Bahadir, MThe objective of this study was to optimize an analytical method for the analysis of selected chlorinated phenols (2-chlorophenol [2-CP], 2,4-dichlorophenol [2,4-DCP], 2,4,6-trichlorophenol [2,4,6-TCP] and pentachlorophenol [PCP]) in wastewater. Following the EPA Method 604, the optimum analytical method consisted of procedures including a liquid-liquid extraction (LLE) (n-hexane as an organic solvent), a derivatization (according to acylation technique by using of pentafluorobenzoylchloride (PFBC1), a clean-up procedure (silica gel, deactivated with 2 % water, as a sorbent material) and GC-ECD quantification. When including each of these above steps in the analytical procedure, the recovery rates of target compounds were obtained to be > 80 % (RSD: < 10 %, [n=3]).Öğe Separation of some priority organic pollutants in wastewater samples by column chromatography(PARLAR SCIENTIFIC PUBLICATIONS (P S P), 2004) Tor, A; Cengeloglu, Y; Aydin, ME; Wichmann, H; Bahadir, MThe aim of this work was to develop a fractionation procedure to separate PCBs and PAHs in wastewater extracts, while simultaneously eliminating the interfering substances, a necessary precondition for analysis with nonselective GC detectors. This was carried out by optimizing the fraction cut-off volume of the eluting solvent and deactivation levels of different adsorbents for column chromatography. Using a combined column (5 g aluminum oxide, deactivated with 5% H2O plus 5 g fully activated silica gel) and cutting off PCB collection, after elution with 50 mL n-hexane, led to satisfactory separation of PCBs and PAHs. The approach of this study was to decrease solvent volume and analysis time during cleanup procedure compared to the US EPA standard methods (EPA Methods 610 and 608 for PAHs and PCBs, respectively).Öğe Simultaneous recovery of Cr(III) and Cr(VI) from the aqueous phase with ion-exchange membranes(ELSEVIER SCIENCE BV, 2005) Tor, A; Buyukerkek, T; Cengeloglu, Y; Ersoz, MThe simultaneous recovery of trivalent and tetravalent chromium ions through charged ion-exchange membranes by using three detachable cells was tested at different current densities. The effect of mono- and divalent valence ions corresponding to trivalent and hexavalent chromium ions in the feed phase was investigated. The recovery factor values of chromium (III) and (VI) ion without current density were obtained and found that it was higher in the absence of binary monovalent and divalent ions, but increased with increasing current density and decreased in the presence of the binary mono- and divalent ions. The transport of both oxidation states of chromium ions through membranes was also correlated with the flux data.Öğe Transport of chromium through cation-exchange membranes by Donnan dialysis in the presence of some metals of different valences(ELSEVIER SCIENCE BV, 2004) Tor, A; Cengeloglu, Y; Ersoz, M; Arslan, GThe transport of a trivalent chromium ion through charged polysulfonated cation-exchange membranes in the presence of metals of different valences under Donnan dialysis conditions was studied as a function of pH gradient at 25degreesC. The recovery factor (RF) values of chromium ion were obtained, and it was found that the RF values decreased with the increasing of the metal valence. The transport of chromium ions through membranes was correlated with the flux data, which depended on the metal valences as well as the structure of the membrane. It was observed that the transport was influenced with H+ ion concentration in the receiver phase.Öğe Transport of hexavalent chromium through anion-exchange membranes(ELSEVIER SCIENCE BV, 2003) Cengeloglu, Y; Tor, A; Kir, E; Ersoz, MThis papers deals with the transport of hexavalent chromium through SB-6407, AFN and ACM anion-exchange membranes in contact with different salt solutions. The effect of salt solutions on the transport of chromium(VI) was investigated. The effect of salt solutions was observed at different sequences and the transport efficiencies of the membranes was found to be in the order SB-6407>AFN>ACM. The transport was found to be highest in a single state.Öğe Ultrasonic solvent extraction of organochlorine pesticides from soil(ELSEVIER SCIENCE BV, 2006) Tor, A; Aydin, ME; Ozcan, SUltrasonic solvent extraction of the organochlorine pesticides (OCP) including alpha-, beta-, gamma- and Delta-hexachlorocyclohexane (HCH), heptachlor, aldrin, o,p'-DDE, dieldrin, p,p'-DDE, p,p'-DDT, methoxychlor, mirex from soil is reported. The extraction procedure was optimized with regard to the solvent type, amount of solvent, duration of sonication and number of extraction steps. Determination of pesticides was carried out by gas chromatography (GC) equipped with electron capture detection (ECD). Twice ultrasonic extraction using 25 mL, of a mixture of petroleum ether and acetone (1/1 v/v) for 20 min of sonication showed satisfactory extraction efficiency. Recoveries of pesticides from fortified soil samples are over 88% for three different fortification levels between 15 and 200 p,g kg(-1), and relative standard deviations of the recoveries are generally below 6%. Real soil samples were analyzed for OCP residues by optimized ultrasonic solvent extraction and shake-flask as well as soxhlet extraction technique. Investigated all extraction methods showed comparable extraction efficiencies. Optimized ultrasonic solvent extraction is the most rapid procedure because the use of time in ultrasonic extraction was considerably reduced compared to shake-flask and soxhlet extraction. (c) 2005 Elsevier B.V. All rights reserved.Öğe Using n-alkanes for identification of oils in domestic wastewaters(SELPER LTD, PUBLICATIONS DIV, 2005) Tor, A; Aydin, ME; Cengeloglu, Y; Ozcan, SThe aim of this work was to investigate whether linear aliphatic hydrocarbons had a usable potential for the determination of waste oil in wastewater. For that, n-alkanes analyses of wastewater samples from five sampling points (P-1-P-5) of the sewage system of Konya-Turkey were carried out by gas chromatographic technique and the parameters of carbon predominance index (ICP), n-C-17/n-C-18 and unresolved complex mixture (UCM)/n-alkanes ratios were determined. It was found that sampling points P, P, and P. which had ICP values 1.52 +/- 0.04, 1.43 +/- 0.05 and 1.12 +/- 0.05, respectively, were polluted with petroleum hydrocarbons and the aliphatic hydrocarbons detected in the sampling points of P, and F, which ad ICP values of 0.96 +/- 0.05 and 0.95 +/- 0.03, respectively, were from natural origin. These results were also supported by the parameters of n-C-12/n-C-18 and UCM/n-alkanes ratios and by the correlation between the parameters of ICP, n-C-17/n-C-18 UCM/n-alkanes and COD, Pb, Cr for all sampling points.
