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Öğe Application of Modified BCR Sequential Extraction Method for the Fractionation and ICP-OES Determination of Copper in Asphaltite Combustion Waste(Atomic Spectroscopy Press Ltd, 2013) Aydin, Firat; Gunduz, Beniz; Aydin, Isil; Akba, Osman; Saydut, Abdurrahman; Hamamci, CandanAsphaltite is derived from petroleum-origin solid fossil fuel. It contains many elements in different forms which may change during the combustion process. This study presents a modified BCR sequential extraction method for the fractionation of copper (Cu) in asphaltite combustion waste (ACW) into four forms (exchangeable, reducible, oxidizable, and residual) and determination by inductively coupled plasma optical emission spectrometry (ICP-OES). The 327.393 nm line was used because it offers highest detectability and is free from major spectral interferences. A two-stage microwave acid digestion program was used for preparation of the samples. The total Cu concentration in the ACW was 104.56 mg kg(-1) dry weight (d.w). The most abundant copper fraction in the studied ACW samples was found as residual fraction of Cu (59.94 mg kg(-1) d.w.). The relative abundances of the remaining Cu fractions in ACW were as follows: exchangeable + water- and acid-soluble (19.07 mg kg(-1) d.w.) > oxidizable (17.49 mg kg(-1)' d.w.) > reducible (7.65 mg kg(-1) d.w.). The results were found to be in good agreement with the certified values. The advantages of the technique include a high degree of automation, good reproducibility, and short analysis time, which makes it the method of choice for the fractionation of Cu.Öğe Chemical Characteristics of Settled Particles during a Dust-Storm(Hard, 2012) Aydin, Firat; Aydin, Isil; Erdogan, Sait; Akba, Osman; Isik, Birgul; Hamamci, CandanMajor synoptic systems bring desert dust from Arabia and the Sahara to Anatolia, Turkey. A study of particulate matter (PM) associated metal content such as As, Al, Cr, Cd, Co, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Se, Sn, and Zn, etc., has been carried out for Diyarbakir, SE Anatolia, Turkey. Results show that the PM10 levels during a dust storm were much higher than in a non-dust-storm period and that four metals (Fe, Al, Cr, Mn) were dominant in settled particles. This research does not only provide background data for air quality management, but also provides valuable information about the chemical composition of the particles.Öğe Chemical fractionation of nickel in asphaltite based bottom ash(Taylor & Francis Ltd, 2013) Aydin, Isil; Aydin, Firat; Kilinc, Ersin; Duz, M. Zahir; Hamamci, CandanAsphaltite, originating from petroleum, contains many kinds of mineral elements derived from its generation. These elements exist in different forms which may change throughout the asphaltite combustion process. Chemical fractionation of nickel (Ni) is necessary for risk assessment of asphaltite based bottom ash (ABBA). This study presents the concentration and fractionation of Ni in bottom ash of asphaltite (Sirnak, SE Anatolia, Turkey). Determination of total Ni in ash was performed in two stage microwave-acid digestion followed by inductively coupled plasma optical emission spectrometry (ICP-OES). Dry ashing is used for the almost complete elimination of organic materials prior to analyte determination. A seven-step sequential extraction process to fractionation of Ni from ABBA was investigated. Total Ni concentration in the ABBA was found to be 568.15 mg kg(-1). The most abundant form of Ni in the ABBA was Ni as sulfide (301.23 mg kg(-1)). Relative abundances of the remaining Ni fractions in ABBA follow the order: Reducible (83.23 mg kg(-1)) > Water soluble (77.94 mg kg(-1)) > Carbonate (35.67 mg kg(-1)) > Exchangeable (28.11 mg kg(-1)) > Oxidisable (25.19 mg kg(-1)) > Residual (16.78 mg kg(-1)). Assessment of chemical, mineralogical, morphological and leaching behaviour of ashes is important for their effective management.Öğe Comparison of the biodiesel quality produced from refined sunflower (Helianthus annuus L) oil and waste cooking oil(Multi-Science Publ Co Ltd, 2010) Saydut, Abdurrahman; Kafadar, Aylin Beycar; Tonbul, Yalcin; Kaya, Canan; Aydin, Firat; Hamamci, CandanA major hurdle in commercialization of biodiesel from vegetable oil, in comparison to petroleum-based diesel fuel, is its cost of manufacturing, primarily the raw material cost. Waste cooking oil is one of the economical sources for biodiesel production. NaOH and KOH catalyzed processes for prepared of biodiesel expressed of fatty acid methyl ester were comparatively studied for refined sunflower (Helianthus annuus L) oil and waste cooking oil. Transesterification was carried out using 100% excess methanol; i.e. molar ratio of methanol to oil is 6:1 and catalyst concentration of 0.5% at 60 degrees C. Fuel properties and specifications such as viscosity, flash point, cloud point, pour point, density, cetane number, and acidic value are determined and compared to each other and petroleum diesel. This study characterizes the fuel properties of biodiesel produced from refined sunflower oil and waste cooking oil using two different catalysts (NaOH and KOH) to provide a comprehensive understanding of biodiesels.Öğe Content and Mobility Behavior of Iron and Manganese in Asphaltite Burning Residue Using ICP-OES(Atomic Spectroscopy Press Ltd, 2014) Aydin, Isil; Gunduz, Beniz; Aydin, Firat; Akba, Osman; Saydut, Abdurrahman; Hamamci, CandanThe determination of inorganic pollutants leaching from solid waste, such as coal, asphaltite, oil shale, and ash, is an important topic for industrial applications and solid waste management. This study presents the concentration and fractionation of iron (Fe) and manganese (Mn) in asphaltite burning residue (ABR) and their determination by inductively coupled plasma optical emission spectrometry (ICP-OES). A modified Tessier sequential extraction method was used for the fractionation of Fe and Mn in four forms (exchangeable, carbonates, bound to organic and sulfide, and residual content). Investigations on the Fe and Mn chemical fractions and their environmental mobility in ash solution systems were carried out. It was found that Mn in ABR (from Harbul-Silopi, Turkey) occurs in the following fractions: exchangeable (13.56%), associated with carbonates (28.94%), associated with organic matter and sulfides (17.48%), and residual content (40.08%). Fe occurs in the following fractions: exchangeable (11.11%), carbonates (27.68%), organic matter and sulfides (23.39%), and residual content (37.82%). Among these fractions, the exchangeable and carbonate-bound fractions are unstable and prone to leach out, while the organic matter-bound fractions and the residual fractions are considered to be relatively stable and of low bioavailability. Thw mobility fractions of Fe contain 38.79% and of Mn contain 42.50% of their total concentration in ABR under normal environmental conditions.Öğe Desulfurization and demineralization of asphaltite using combination of froth flotation and aqueous caustic leaching(Sage Publications Inc, 2008) Saydut, Abdurrahman; Duz, M. Zahir; Aydin, Isil; Hamamci, CandanThe mineral matter and Sulfur, which are present in varying amounts in asphaltites, are a major problem in utilization of asphaltites as a fuel. The effect of leaching asphaltites from Simak and Silopi, SE Anatolia, Turkey, with froth flotation following aqueous sodium hydroxide oil desulfurization and deashing was investigated. Froth flotation reduced the ash content of asphaltite by 35.8 % and 35.3 %, pyritic Sulfur 22.55 % and 8.7 % (wt %) and its volatile matter content by 28.9 % and 28.9 %. The asphaltite flotation yield was 79.1 % and 85.3 %. Never organic sulfur could be removed by froth flotation. The asphaltite concentration obtained from flotation was leached using aqeous sodium hydroxide and its organic sulfur content was reduced by 60.8% and 61.9 %. Hence using combination of the two methods, the total sulfur, ash and volatile matter contents was reduced by 76.4% and 71.4 %, 38.1 % and 38.3 %, 44.1 % and 47.2 %. respectively.Öğe Determination of mineral phosphate species in sedimentary phosphate rock in Mardin, SE Anatolia, Turkey by sequential extraction(Elsevier Science Bv, 2009) Aydin, Isil; Imamoglu, Sefik; Aydin, Firat; Saydut, Abdurrahman; Hamamci, CandanThe importance of the effect of phosphate rock depends on the chemical form of phosphorus in which this element is combined. The paper presents the results of inorganic and organic forms of phosphorus in the phosphate rock from Mazidag-Derik, Semikan deposit located at Mardin city at SE Anatolia of Turkey. Total phosphorus concentration in the rock is an average 18.5%. The inorganic phosphorus mean % contents were 99.98% for studied sedimentary phosphate rock. Speciation of inorganic phosphorus was carried out using a method based on sequential extractions of the sedimentary phosphate rock each releasing four forms of inorganic phosphorus: loosely sorbed phosphorus, phosphorus bound to aluminium (P-Al), phosphorus bound to calcium (P-Ca) and phosphorus bound to iron (P-Fe). Calcium bound phosphorus is the dominant form of inorganic phosphorus in the studied sedimentary phosphate rock. Aluminium bound phosphorus is the second, iron bound phosphorus is the third most prevailing form. Loosely bound phosphorus is present in the lowest amounts. Analyses of phosphorus forms in sedimentary phosphate rock using a UV spectrophotometric method and ICP-AES are reported here. For the phosphorus the two methods give the same results and the concentrations are in good agreement with the reference values. (C) 2008 Elsevier B.V. All rights reserved.Öğe Froth flotation pretreatment for enhancing desulfurization of coal with sodium hydroxide(Natl Inst Science Communication, 2007) Saydut, Abdurrahman; Tonbul, Yalcin; Baysal, Akin; Zahir Duz, M.; Hamamci, CandanFroth flotation (FF) pretreatment of coal from Hazro, Turkey, for enhancing desulfurization with sodium hydroxide was investigated. FF reduced following contents of coal: ash, 58.54; pyritic sulfur, 79.34; and volatile matter, 56.98%. The coal flotation was 69.59%. FF could not remove organic sulfur Coal concentration obtained from flotation was leached using aqueous NaOH and its organic sulfur content was reduced by 59.27%. Hence using combination of two methods, total sulfur, ash and volatile matter, contents was reduced by 88.06%, 63.13% and 77.32%, respectively.Öğe Hazardous metal geochemistry of sedimentary phosphate rock used for fertilizer (Mazidag, SE Anatolia, Turkey)(Elsevier, 2010) Aydin, Isil; Aydin, Firat; Saydut, Abdurrahman; Bakirdere, E. Gulhan; Hamamci, CandanComposition of phosphate rocks mostly depend on their type and origin. Sedimentary rocks contain high concentration of heavy metals. Phosphate rocks are mainly used for the manufacturing of phosphate fertilizers. The contents of heavy metals Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn, as well as rare earth elements Ce, La, and Th were determined in sedimentary phosphate rock used for production of fertilizer in Turkey. The Kasrik-Semikan, Mazidag (Mardin, SE Anatolia, Turkey) high-grade phosphate rock used in this study is situated near the border with Syria and was deposited during the Turonian and Senonian (Cretaceous) ages. Total phosphorus (P) concentration in the rock is 18.5% on the average. Microwave acid digestion (MW-AD) followed by inductively Coupled Plasma-Optical Emission Spectrophotometry (ICP-OES) was carried out for the determination of all the elements of interest in phosphate rock. The results revealed that hazardous metal content of the phosphate rock was lower in Mazidag phosphate than that in samples imported from other countries and were within the safety limits. (C) 2010 Elsevier B.V. All rights reserved.Öğe High-Performance Liquid Chromatography Analysis and Assessment of Benzoic Acid in Yogurt, Ayran, and Cheese in Turkey(Springer, 2012) Yildiz, Aydin; Erdogan, Sait; Saydut, Abdurrahman; Hamamci, CandanAmong food sources, particular attention is paid to milk and dairy products, due to its nutritional importance. Benzoic acid is extensively used in the preservation of foods. A reliable method for the determination of benzoic acid in some dairy products, such as yogurt, ayran, and cheese using high-performance liquid chromatography and UV detection was validated. The peak of benzoic acid was measured at a wavelenght of 226 nm. Samples were purchased from supermarkets in Turkey in the period 2009-2010. All dairy product samples were produced from cow's milk. The levels of benzoic acid in cheese, yogurt, and ayran samples were in the range of 3.17 to 56.77 mg kg(-1), 8.94 to 28.30 mg kg(-1), and 1.54 to 16.57 mg L-1, respectively. The results show that benzoic acid widely occurs in milk products in Turkey at the low levels.Öğe Influences of temperature on flash pyrolysis products of asphaltite(Natl Inst Science Communication, 2008) Saydut, Abdurrahman; Hamamci, CandanSeguruk (Sirnak, Turkey) asphaltite by flash pyrolysis in a fixed bed reactor with a heating rate 40 degrees C min(-1) at 400-800 degrees C (optimum 550 degrees C) under nitrogen atmosphere gave: solid residue (char), 67.68; oil, 13.28; and water, 0.99%. Seguruk asphaltite contained: asphaltene, 28.72; preasphaltene, 10.43; aliphatics, 52.54; aromatics, 5.05; and polar aromatic Compounds, 3.26%. Oil obtained from asphaltite is mainly aliphatic according to FTIR spectrum.Öğe Liquefaction of Harbul (Silopi SE anatolia, turkey) asphaltite by flash pyrolysis(Sage Publications Inc, 2008) Saydut, Abdurrahman; Tonbul, Yalcin; Hamamci, CandanAsphaltite, being petroleum originated solid fossil fuel, can be converted into a variety of secondary products such as light hydrocarbon gases, liquid product and high quality fuel char by means of pyrolysis. Liquefaction of Harbul (Silopi, Turkey) asphaltite, -0.60+0.25 mm particle size, and using flash pyrolysis was performed in a fixed bed reactor with a heating rate 40 degrees C min(-1) at a temperature ranging from 400 to 800 degrees C under nitrogen atmosphere. The effect of temperature on conversion and liquid yield was examined. The flash pyrolysis temperature resulted in a large increase in the oil yield, tar, gases, large increase in the yield of hydrocarbon gases occurred as a result of temperature at 550 degrees C which was attributed to an increase thermal cracking of pyrolysis vapours. The yield of asphaltite liquid at the condition of 550 degrees C reached a maximum 19.66 wt %. The asphaltenes of the pyrolytic oils were precipitated by addition of n-pentane. Pentane solubles were fractioned by column chromatography into aliphatic, aromatic and polar fractions using n-hexane, toluene and methanol, respectively. The composition of these fractions from silica gel column chromatography of oil obtained by nitrogen pyrolysis was characterized by FTIR.Öğe Major and Trace Element Contamination of Short-Term Snow Cover During and After a Dust Storm and Analysis by ICP-OES(Atomic Spectroscopy Press Ltd, 2013) Akba, Osman; Kilinc, Ersin; Aydin, Isil; Erdogan, Sait; Aydin, Firat; Duz, M. Zahir; Hamamci, CandanThe levels of major and trace elements are key data for evaluating the toxicity of potential particulate matter and for identifying pollution sources. From this point of view, snow is considered an ideal matrix to observe deposition from the atmosphere due to environmental and anthropogenic activities. This work has demonstrated that major and trace element levels of Al, As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Se, Sn, and Zn were found in snow precipitation sampled during and after a dust storm in and around Diyarbakir city, SE Anatolia, Turkey. A simple methodological approach consisting of surface snow sampling and analysis by ICP-OES provides information about the spatial distribution and temporal evolution of atmospheric precipitation. The concentrations of toxic metals were found at high levels and are therefore a threat to human health. In particular, the concentrations for Fe and Al were significantly higher than for the other elements.Öğe Methyl ester of peanut (Arachis hypogea L.) seed oil as a potential feedstock for biodiesel production(Pergamon-Elsevier Science Ltd, 2009) Kaya, Canan; Hamamci, Candan; Baysal, Akin; Akba, Osman; Erdogan, Sait; Saydut, AbdurrahmanThe peanut (Arachis hypogea L.) seed oil was extracted from the seeds of the peanut that grows in SE Anatolia of Turkey. Oil was obtained in 50 wt/wt.%, by solvent extraction. Peanut (A. hypogea L) seed oil was investigated as an alternative feedstock for the production of a biodiesel fuel. Biodiesel was prepared from peanut by transesterification of the crude oil with methanol in the presence of NaOH as catalyst. A maximum oil to ester conversion was 89%. The viscosity of biodiesel oil is nearer to that of petroleum diesel and the calorific value is about 6% less than that of diesel. Peanut seed oil have about 8.3% less heating value than that of diesel oil due to the oxygen content in their molecules. The quality of biodiesel is most important for engine part of view and various standards have been specified to check the quality. The important properties of peanut oil and its methyl ester (biodiesel) such as density, kinematic viscosity, flash point, iodine number, neutralization number, pour point, cloud point, cetane number are found out and compared to those of no, 2 petroleum diesel, ASTM and EN biodiesel standards. The comparison shows that the methyl ester has relatively closer fuel properties to diesel than that of raw peanut seed oil. (C) 2008 Elsevier Ltd. All rights reserved.Öğe Microwave assisted transesterification of maize (Zea mays L.) oil as a biodiesel fuel(Sage Publications Inc, 2010) Ozturk, Gulsen; Kafadar, Aylin Beycar; Duz, M. Zahir; Saydut, Abdurrahman; Hamamci, CandanMaize (Zea mays L.) oil is a highly valuable agricultural commodity for the Turkey. Transesterified maize oil has the global better properties because it has the greater monounsaturated content. Biodiesel has been prepared from maize by transesterification of the crude oil under microwave irradiation, with methanol to oil molar ratio of 10:1, in the presence of 1.5% NaOH as catalyst and 5 minutes time, the conversion of maize oil to methyl ester was over 98%. Compared with conventional heating methods, the process using microwaves irradiation proved to be a faster method for alcoholysis of triglycerides with methanol, leading to high yields of biodiesel.Öğe Microwave Digestion Followed by ICP-OES for the Determination of Al, Cd, Cr, Cu, Fe, Ni, Pb, and Sn in Maize(Atomic Spectroscopy Press Ltd, 2012) Duz, M. Zahir; Celik, K. Serdar; Aydin, Isil; Erdogan, Sait; Aydin, Firat; Hamamci, CandanMaize (Zea mays L.) is currently the most widely grown crop in the world and is used not only for food and animal feed but also to produce industrial starches, biodiesel, ethanol, and oils. The present work reports the results obtained by the proposed method for the determination of metals (M, Cd, Cr, Cu, Fe, Ni, Pb and Sn) in maize by ICP-OES, using digestion with an oxidant mixture in a closed-vessel microwave oven. The results in the maize samples (minimum-maximum in mg/kg) were: Al 6.678-7.051, Sn 2.092-3.977, Cr 0.394-0.423, Cu 21.56-24.78, Fe 93.37-102.86, Ni 1.679-1.877 and Pb 0.375-0.392. The concentration of Cd was below the detection limit (< 0.03 mg/kg). The certified reference material, CRM NIST1573a Tomato Leaves, was used in order to verify the accuracy of the microwave digestion method. The results of this study were in good agreement with the certified values.Öğe Molybdenum speciation in asphaltite bottom ash (Seguruk, SE Anatolia, Turkey)(Elsevier Sci Ltd, 2012) Aydin, Isil; Aydin, Firat; Hamamci, CandanAsphaltites derive from petroleum origin. The combustion of asphaltites produces fly and bottom ashes that are characterized by a high content of valuable elements such as vanadium, nickel, molybdenum, uranium, thorium, sulfur and unburnt carbon. This study presents the concentration and speciation of molybdenum in bottom ash of asphaltite (Seguruk, SE Anatolia, Turkey). Determination of total molybdenum in asphaltite bottom ash was performed in two stage microwave-acid digestion followed by inductively coupled plasma optical emission spectrometer. A seven step sequential extraction process to speciation of molybdenum from asphaltite bottom ash was investigated. The most abundant form of molybdenum in samples is sulfide fraction of molybdenum. Relative abundances of the remaining fractions follow the order: residual > reducible > oxidizable > exchangeable > carbonate > water soluble. Molybdenum speciation scheme allows quantitative knowledge of molybdenum distribution in asphaltite bottom ash and their toxicity, mobility, leachability, bioaccumulation and bioavailability. (C) 2011 Elsevier Ltd. All rights reserved.Öğe Phosphorus Speciation in Coal Bottom Ash(Atomic Spectroscopy Press Ltd, 2011) Aydin, Firat; Saydut, Abdurrahman; Aydin, Isil; Hamamci, CandanCoal, coal bottom ash (CBA), and coal fly ash contain many elements in different forms which may change during the coal combustion process. A true understanding of the dynamics of phosphorus (P) in the natural environment requires an expanded knowledge of its oxidation-reduction (redox) cycling. This study presents a sequential extraction method for the speciation of phosphorus from CBA in seven forms and their determination by inductively coupled plasma optical emission spectrometry (ICP-OES). The total P concentration in CBA was found to be 651.48 mg kg(-1). The most abundant form of P in CBA is the sulfide fraction of P (40.42%). The relative abundances of the remaining P fractions follow the order: Residual 38.63% > Reducible 15.12% > Carbonate 3.42% > Oxidizable 1.10% > Exchangeable 0.94% > Water soluble 0.37%.Öğe Phosphorus Speciation in the Surface Sediment and River Water from the Orontes (Asi) River, Turkey(Water Environment Federation, 2010) Aydin, Isil; Aydin, Firat; Hamamci, CandanThe paper presents the results of the distribution of phosphorus bioavailability (total, organic, and inorganic phosphorus) in surface sediment and river water from the Orontes (Asi) River (Samandag, Antakya, Turkey) in March 2008. Speciation of inorganic phosphorus was carried out using a method on sequential extractions, with each releasing four forms of inorganic phosphorus-loosely sorbed phosphorus, phosphorus bound to aluminum (P-Al), phosphorus bound to iron (P-Fe), and phosphorus bound to calcium (P-Ca). Total phosphorus concentrations are, on average, 3.724 mg/L and 312.30 mg/kg dry weight in the river water and surface sediment, respectively. The interstitial water of the surface sediment contains less than 1% of the surface sediment's total phosphorus pool. The most abundant form of inorganic phosphorus is P-Ca. Relative abundances of the remaining phosphorus forms both in surface sediment and river water follow the order P-Al > loosely bound-P> P-Fe. Water Environ. Res., 82, 2265 (2010).Öğe Process optimization for production of biodiesel from hazelnut oil, sunflower oil and their hybrid feedstock(Elsevier Sci Ltd, 2016) Saydut, Abdurrahman; Erdogan, Sait; Kafadar, Aylin Beycar; Kaya, Canan; Aydin, Firat; Hamamci, CandanThe most important constituent needed for biodiesel development is the feedstock. As the availability of feedstock is limited, the possibility of using the hybrid feedstock has been explored. Biodiesel has been synthesized from hazelnut (Corylus avellana L.) kernel oil, sunflower (Helianthus annuus L.) oil and hybrid (hazelnut and sunflower) (50: 50 v/v) feedstocks. Ester yield of vegetable oil to fatty acid methyl esters (FAME) was found to be 97.5%, 97.3% and 97.9% for hazelnut, sunflower and hybrid feedstocks respectively. The reaction parameters were used to be 6: 1 (methanol to oil) molar ratio, KOH (0.7%), at 60 +/- 0.5 degrees C for 2 h during alkali esterification for the three feedstocks. High yield from hybrid feedstock during transesterification reaction clearly indicated that the reaction was not selective for any particular oil. The obtained results important in that in case of scarcity of feedstock both oils could be mixed as well to maintain the constant supply of the feedstock in the perspective of industrial production of biodiesel. (C) 2016 Elsevier Ltd. All rights reserved.
