Bazı fenolik bileşiklerin kromatografik tayinleri

Bu tezin, veri tabanı üzerinden yayınlanma izni bulunmamaktadır.Yayınlanma izni olmayan tezlerin basılı kopyalarına üniversite kütüphaneniz aracılığı ile (TÜBESS üzerinden) erişebilirsiniz.Bu çalışmada, eser miktarda 2,4-DCP, 2,6-DCP, 2,4,6-TCP, 2,3,4,6-TeCP ve PCP'ün gaz kromatografisi kütle spektrometresi ile tayini için yeni bir dispersif sıvı-sıvı mikroekstraksiyon (DLLME) yöntemi geliştirildi. Önerilen yöntemin örnek hacmi, pH, dispersif çözücü türü ve hacmi, ekstraksiyon çözücü türü ve hacmi ve ekstraksiyon süresi gibi farklı değişkenleri istatistiksel deneysel tasarım olan "Plackett-Burman Faktöriyel Tasarım" ile optimize edildi. Yöntemin doğruluğu analit ekleme yöntemi kullanılarak gösterildi. 2,4-DCP, 2,6-DCP, 2,4,6-TCP, 2,3,4,6-TeCP ve PCP'ün geri kazanımları % 6,6'dan küçük BSS ile iç standartlı ve iç standartsız olarak sırasıyla % 69, 72, 93, 100 ve 101 bulundu. DLLME-GC-MS yönteminin gözlenebilme sınırları ve deneysel deriştirme faktörleri sırasıyla 2,4-DCP, 2,6-DCP, 2,4,6-TCP, 2,3,4,6-TeCP ve PCP için (0,226, 0,144, 0,014, 0,010 ve 0,014 ?g L-1) ve (80, 89, 106, 113 ve 115) bulundu.Tezin ikinci kısmında, GC-MS tayini öncesi asetik anhidrit ile türevlenen fenolik bileşiklerin (2,6-DCP, 2,4,6-TCP, 2,3,4,6-TeCP, PCP, 4-MP, 2,4-DMP, 4-EP, 4-t-BP, o-PP, 4-t-OP ve 4-n-NP) deriştirilmesi için adsorban olarak Dowex 1x16 reçinesinin (kuvvetli anyon değiştirici) kullanıldığı yeni bir katı faz ekstraksiyon (SPE) yöntemi geliştirildi. Fenoller, Dowex 1x16 üzerinde fenolat iyonları formunda adsorplandı ve hekzan ile elüe edildi. SPE yönteminde örnek hacmi, NaOH derişimi, türevleyici reaktif türü ve hacmi, reaksiyon süresi, reçine miktarı, örnek akış hızı ve reçine kurutma süresi gibi değişkenler optimize edildi. SPE yöntemi analit ekleme yöntemiyle doğrulandı. Optimum şartlarda SPE ile deriştirilen analitlerin pik alan oranlarının BSS'ları % 2,1 (4-t-OP) ile 6,7 (4-MP) arasında elde edildi. Gözlenebilme sınırları (GS) 0,005 (4-n-NP) ile 1,796 µg L-1 (4-MP) aralığında bulundu. Yöntem 100 mL örnek hacmi ile çalışmaya uygundur ve son olarak analitler 50 µL'ye toplandı ve deriştirildi. Böylece zenginleştirme faktörü hacim oranından 2000 olarak bulundu. Önerilen yöntem gerçek örneklere (su ve meyve suyu) başarıyla uygulandı.Anahtar Kelimeler: Klorfenol, Alkilfenol, Türevleme, GC-MS, DLLME, SPE, Deneysel tasarım, Su, Meyve suyuIn this work, a new dispersive liquid-liquid microextraction (DLLME) method was developed for the determination of trace amounts of 2,4-DCP, 2,6-DCP, 2,4,6-TCP, 2,3,4,6-TeCP and PCP by gas chromathography mass spectrometry. Different parameters i.e., sample volume, pH, type and volume of dispersive solvent, extraction solvent type and volume and time of extraction of proposed method were optimized by a statistical experimental design ?Plackett-Burman Factorial design?. The accuracy of the method was performed using standart addition method. The recovery of 2,4-DCP, 2,6-DCP, 2,4,6-TCP, 2,3,4,6-TeCP and PCP were found 69, 72, 93, 100 and 101%, respectively with RSD 6.6% with and without internal standard. In DLLME-GC-MS method, detection limits and experimental preconcentration factors were found (0.226, 0.144, 0.014, 0.010 and 0.014 ?g L-1) and (80, 89, 106, 113 and 115) were obtained for 2,4-DCP, 2,6-DCP, 2,4,6-TCP, 2,3,4,6-TeCP and PCP respectively.In the second part this thesis, a novel solid phase extraction (SPE) method was developed using Dowex 1x16 resin (a strong anion-exchanger) as adsorbent for preconcentrations of derivatizated pholic compounds (2,6-DCP, 2,4,6-TCP, 2,3,4,6-TeCP, PCP, 4-MP, 2,4-DMP, 4-EP, 4-t-BP, o-PP, 4-t-OP and 4-n-NP) with acetic anhydride prior to GC-MS determination. The phenols adsorbed on Dowex 1x16 as phenolate ions and eluated with hexane. Several variables of SPE methods like sample volume, concentration of NaOH, type and volume of derivatization reagent, reaction time, amount of resin, sample flow rate and drying time for resin were optimized. The SPE method was validated with standart addition method. The RSDs of peak area ratio of SPE at optimum conditions were obtained in the range of 2.1 (4-t-OP) to 6.7 % (4-MP). The limit of dedection (LODs) were found in between 0.005 ( 4-n-NP) to 1.796 µg L-1 (4-MP). The method was allowed to work with 100 mL sample volume and finally analytes were collected and concentrated to 50 ?L. Thus, enrichment factor was found as 2000 from volume ratios. The proposed methods were successfully applied on real samples (water and fruit juices).Keywords: Chlorophenol, Alkylphenol, Derivatization, GC-MS, DLLME, SPE Factorial Design, Water, Fruit juic

Determination of Chlorophenols in Wastewater with Methyl Chloroformate Derivatization, Solid Phase Extraction, and Gas Chromatography–Mass Spectrometry

The determination of chlorophenols in wastewater with methyl chloroformate derivatization, solid phase extraction, and gas chromatography–mass spectrometry is reported. In order to employ this combined solid phase derivative extraction method, quantitative extraction was performed by the introduction of 100 mL of sample in 1.0 mol L−1 sodium hydroxide into a column containing 500 mg of packed resin at a flow rate of 1.0 mL/min. The chlorophenols were retained and derivatized quantitatively in the column by the introduction of 0.25 mL of methyl chloroformate. The derivatized analytes were eluted with 5.0 mL of hexane before the effluent was dried under a stream of nitrogen. The dried solution was diluted to a volume of 50 µL with hexane followed by analysis by gas chromatography–mass spectrometry. The preconcentration parameters were optimized and under these conditions: limits of detection from 0.010 to 0.423 µg L−1, a preconcentration factor of 2500, and precision values from 4.8 to 7.7% as the relative standard deviation were obtained. The method was employed for the analysis of water samples and the recoveries of the analytes were between 76 and 103%. © 2015, Copyright © Taylor & Francis Group, LLC

Solid phase extraction method for the determination of iron, lead and chromium by atomic absorption spectrometry using Amberite XAD-2000 column in various water samples

This work describes a procedure for the separation-preconcentration of Fe(III), Pb(II) and Cr(III) from some water samples using a column-filled Amberlite XAD-2000 resin. The analyte ions retained on the column were eluted with 0.5 mol L-1 HNO3. The analytes in the effluent were determined by atomic absorption spectrometry. Several parameters governing the efficiency of the method were evaluated including pH, resin amount, sample volume, flow rates, eluent type and divers ion effects. The recoveries under the optimum working conditions were found to be as 100 ± 1% Fe, 96 ± 1% Pb and 93 ± 2% Cr. The relative standard deviations and errors were less than 2% and 5%, respectively. The detection limit based on three standard deviations of the blank was found to be 0.32, 0.51 and 0.81 µg L-1, for Fe, Pb and Cr, respectively. The procedure was applied to the determination of Fe, Cr and Pb in hot spring water and drinking water samples. © 2007 Elsevier B.V. All rights reserved

Lead biosorption by magnetic Pisum sativum peel biocomposite using experimental design

The Pisum sativum has been used as a magnetic biocomposite biosorbent for the removal of lead ions from aqueous solutions. These biocomposites were prepared with encapsulated alginate beads into calcium chloride solution, Pisum sativum peel powder and iron (II–III) oxide. Properties of surface and the possible binding sites of the material were evaluated by instrumental analysis using Fourier transform infrared spectroscopy-attenuated total reflection, scanning electron microscope, and X-ray diffraction. Scanning electron microscopy–energy-dispersive X-ray spectroscopy and mapping techniques are also used for evaluation of process. Optimisation of biosorption procedure was done by Plackett–Burman factorial design including parameters such as biocomposite amount, pH, temperature and extraction time. The analytical performance of the biosorption method, application to industrial effluent, the reusability and stability of biosorbent were also investigated. The Pisum sativum magnetic biocomposite adsorbed 90 ± 4% of lead at the optimum pH value 4 and 125 mg biocomposite amount. The best-fitting isotherm model is Freundlich and theoretical capacity of biosorbent was calculated as 74.05 mg/g. The report of magnetic Pisum sativum biocomposite as a biosorbent may be used as natural renewable resources and reduces the adverse effects on water contaminated for lead. © 2021 Informa UK Limited, trading as Taylor ; Francis Group.2018 HZDP024, 2018 KKP181, 2018KRM002; Pamukkale Üniversitesi, PAÜThe authors would like to thank the Scientific Research Projects (SRP) Coordination Unit of Pamukkale University for financially supporting this research and conference with project numbers 2018 HZDP024 and 2018 KKP181 (2018KRM002).The authors would like to thank the Scientific Research Projects (SRP) Coordination Unit of Pamukkale University for financially supporting this research and conference with project numbers 2018 HZDP024 and 2018 KKP181 (2018KRM002)

Preconcentration of Pb(II), Cr(III), Cu(II), Ni(II) and Cd(II) ions in environmental samples by membrane filtration prior to their flame atomic absorption spectrometric determinations

A method for separation-preconcentration of Pb(II), Cr(III), Cu(II), Ni(II) and Cd(II) ions by membrane filtration has been described. The method based on the collection of analyte metal ions on a cellulose nitrate membrane filter and determination of analytes by flame atomic absorption spectrometry (FAAS). The method was optimized for several parameters including of pH, matrix effects and sample volume. The recoveries of analytes were generally in the range of 93-100%. The detection limits by 3 sigma for analyte ions were 0.02 µg L-1 for Pb(II), 0.3 µg L-1 for Cr(III), 3.1 µg L-1 for Cu(II), 7.8 µg L-1 for Ni(II) and 0.9 µg L-1 for Cd(II). The proposed method was applied to the determination of lead, chromium, copper, nickel and cadmium in tap waters and RM 8704 Buffalo River Sediment standard reference material with satisfactory results. The relative standard deviations of the determinations were below 10%. © 2006 Elsevier B.V. All rights reserved

Ion pair-dispersive liquid-liquid microextraction coupled to microsample injection system-flame atomic absorption spectrometry for determination of gold at trace level in real samples

A novel ion pair-dispersive liquid-liquid microextraction (IP-DLLME) of gold followed by its determination with microsample injection system - flame atomic absorption spectrometry (MIS-FAAS) was developed. The extraction method was based on the reaction of anionic tetrachloro gold(III) complex with the cationic form of Rhodamine B to give a violet ion pair complex, which is extracted from 1.0 mol L-1 HCl solution of 8.0 mL to fine droplets of chloroform of 500 μL. A Plackett-Burman experimental design of MINITAB statistical program was employed to optimize the influence of main parameters to be controlled in DLLME. After optimizing the extraction conditions, gold was quantitatively recovered by preconcentration factor 40, limit of detection (LOD) 1.8 μg L-1 and relative standard deviation less than 6.8%. The proposed method was successfully applied to the preconcentration and determination of gold in some samples such as tap water, waste water, copper electrolysis solution and copper wire coated with nickel

Dispersive Liquid-Liquid Microextraction of Nickel Prior to Its Determination by Microsample Injection System-Flame Atomic Absorption Spectrometry

A sensitive and simple method for the determination of trace nickel was developed by the combination of dispersive liquid-liquid microextraction (DLLME) and microsample injection system-flame atomic absorption spectrometry (MIS-FAAS). Trace nickel was preconcentrated as the 8-hydroxyquinoline chelate by DLLME, and the conditions were optimized by a Plackett-Burman design. Quantitative recovery of nickel (98 ± 1%) was obtained by a sample volume of 7.5 mL at a pH of 6.0. The enrichment factor was 52.5, and the limits of detection and quantitation were 0.1 μ g L-1 and 3.0 μ g L-1, respectively. The method was validated by the analysis of a wastewater standard reference material, water samples, and a wire sample. The reported method has superior analytical figures of merit compared with similar methods reported in the literature. © 2014 Taylor & Francis Group, LLC

Characterization, modification and use of biomass: Okra fibers

In the present study, fibers were extracted from different parts of okra stem and branches by way of biological retting. The extracted fibers were subjected to chemical and enzymatic treatments. The effects of the treatments on the fibers’ physical, mechanical, chemical and morphological aspects were investigated. The dyeability of the fibers with industrial green mate (Paraguayan tea) waste was studied. The heavy metal ion adsorption capability of okra bast fibers from aqueous systems was examined. The ranges for properties of the produced okra bast fibers can be summarized as linear density of 14·7-26·9 tex (g/km), initial modulus of 862-1358 cN/tex, breaking tenacity of 24-35 cN/tex, elongation of 2·5-3·2% and water absorption of 67·2-84·8%. As a mordant, iron sulfate resulted in higher color strength (K/S) for fibers dyed with the green mate tea waste compared to potassium aluminum sulfate (alum). Use of okra bast fibers resulted in iron (III), copper (II) and chromium (III) ion concentration decreases, as high as 71-98%, in aqueous solutions for pH values under 7. © 2016, ICE Publishing. All rights reserved

Heavy metals separation and determination in waters using MIS-FAAS by bismuth(III) hydroxide co-precipitation method

Potable and urban waters, which is a vital resource, constitute the most basic research area of today. In the current study, a newly optimized co-precipitation method using bismuth(III) hydroxide has been examined for quantitative separation and preconcentration of iron(III), chromium(III), copper(II), cobalt(II), manganese(II), nickel(II), and cadmium(II) ions from water samples. Analytes were co-precipitated and after dissolving analyzed by micro-sample injection system flame atomic absorption spectrophotometry. The influence of variables such as sample volume, sodium hydroxide concentration, bismuth(III) concentration, matrix effects, etc. were investigated. The theoretical enrichment factor of the optimized method is 50. The precisions of within-day and intra-day for the analyte elements working real water samples were found in the range of 4.1-4.5. The limit of detections for the analyte elements were in the range of 0.8-9.5 mu g/L. The limit of quantification of iron(III), chromium(III), copper(II), cobalt(II), manganese(II), nickel(II), and cadmium(II) ions were calculated to be 18.0, 21.0, 7.6, 6.8, 13.0, 27.0, and 1.1 mu g/L, respectively. The analysis of the BCR-715 standard reference water sample demonstrated the procedure's accuracy, and the method was successfully applied to two different water samples and nine different plants as a real sample.Scientific Research Projects (SRP) Coordination Unit of Pamukkale University [2006FEF13]The authors would like to thank the Scientific Research Projects (SRP) Coordination Unit of Pamukkale University for financially supporting this research and conference with project number 2006FEF13

Determination of Pesticides in Soil by Mechanical Stirring-Assisted Extraction Coupled with Gas Chromatography-Mass Spectrometry

This work describes the development of an analytical method for determining the mobility of some organophosphorus and azole group pesticides. The chromatographic and mass spectrophotometric parameters were optimized. The target pesticides were recovered quantitatively (79.3-95.6%) with a relative standard deviation less than 8.5% at the optimum conditions of the extraction. The limits of detection of the target pesticides were found to be in the range of 0.16 to 1. 14 µ g kg -1 with a correlation coefficient (r) > 0. 9955. The method was validated in the target environmental matrices by the analysis of a spiked soil sample. The proposed method was successfully applied for the determination of pesticides in vineyard soil samples and statistically evaluated. © 2014 Copyright Taylor ; Francis Group, LLC