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Öğe Alkali catalyzed transesterification of safflower seed oil assisted by microwave irradiation(Elsevier, 2011) Duz, M. Zahir; Saydut, Abdurrahman; Ozturk, GulsenThe safflower (Carthamus tinctorius L) oil was extracted from the seeds of the safflower that grows in Diyarbakir, SE Anatolia of Turkey. Biodiesel has been prepared from safflower seed by transesterification of the crude oil under microwave irradiation, with methanol to oil molar ratio of 10:1, in the presence of 1.0% NaOH as catalyst. The conversion of C. tinctorius oil to methyl ester was over 98.4% at 6 min. The important fuel properties of safflower 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. 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. (C) 2010 Elsevier B.V. All rights reserved.Öğe Assessment of the Relationship Between Humic Acid Contents and Trace Elements of Some Agricultural Soils in Diyarbakır Region by Multivariate Statistical Methods(Kahramanmaras Sutcu Imam Univ Rektorlugu, 2024) Duzgun, Mehmet; Eren, Abdullah; Bilge, Ugur; Ceylan, Ramazan; Selcuk, Ramazan; Duz, M. ZahirThere are important relationships between humic acid (HA) and the bioavailability, reactions and mobility of trace elements in the soil. For this reason, soils are tried to be improved chemically, biologically and physically with HA applications. In this study, the relationship of humic acid contents of 118 agricultural soil samples from Diyarbakir region with some trace elements (Al, As, Ba, Be, Cd, Fe, Mn, Pb, Sb, Sn, Se, V and P) was evaluated by multivariate statistical analysis. After the soil samples were solubilized by the microwave wet digestion method, the element contents were determined with the ICP OES (Inductively Coupled Plasma Optical Emission Spectrometer) device. SRM NIST 2586 was used as SRM (Standard Reference Material) for the accuracy of the method. Recovery values were found between 91.6% and 105.9% as a result of the analysis. Humic acid was extracted from soils by the International Society for Humic Substances (IHSS) method and determined using a shaker and centrifuge device. For the accuracy of the method, it was tested with Humic Acid Sodium Salt (HA-Na). Pearson correlation and partial correlation analysis were applied to the obtained data set. In addition, multivariate statistical analyses such as multiple regression HCA (Hierarchical Cluster Analysis) and PCA (Principal Component Analysis) were applied. Multiple regression analysis was performed according to the Step-wise method. Manganese and P (p< 0.01) were significant when HA was taken as the dependent variable. According to the Pearson correlation coefficient, the correlation between HA and As (r = -0.282**) in soil was negative and significant, while Fe (r = 0.185*), Mn (r = 0.273**)), Sn (r = 0.242*), Se (r = 0.325**) and P (r = 0.315**) were determined as positive and significant. In clustering and PCA analysis, HA, P Mn and Fe were found to be in the same group. The analyses have shown that HA has a positive effect on the plant nutrients in the soil.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 Cloud Point Extraction As a Preconcentration Step for Flame Atomic Absorption Spectrometric Determination of Pb(Atomic Spectroscopy Press Ltd, 2012) Kilinc, Ersin; Aydin, Firat; Duz, M. ZahirCloud point extraction was employed as a pre-concentration method for the determination Of trace amounts of lead (Pb) after formation of a complex with (4-(2-pyridyi-azo)-resorcinol) (PAR) and later analysis by flame atomic absorption spectrometry (FAAS) using polkoxyethylene-7.5 octylphenyl-ether (Triton, X-114) as surfactant. After phase separation, based on the cloud, point separation of the mixture; the surfactant-rich phase was diluted with 1.0 mol L-1 HNO in methanol. The parameters affectmg the separation of the phases and the detection process were optimized. Under the optimum experimental conditions [i.e., pH 9.0, 2.0(-4) L-1 of PAR, 0.1% (w/v) Triton X-114 1 the detection limits were 2.1 and 1.6 ng mL(-1) for 30.0 and 40.0 mL solutions, respectively. The sensitivity of FAAS was improved by 31.0- and 43.7-fold for 30.0 and 40.0 mL of initial volumes, respectively. The developed method Was applied to the determination of lead in water samples with satisfactory results. The method was validated by employing certified wastewater CWW-TM-D and spiked/fortified water. NWTM-15.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 Geochemical Multi-element ICP-OES Analysis of Borehole Waters from SE Anatolia(Atomic Spectroscopy Press Ltd, 2016) Duz, M. Zahir; Sagirdag, Mehmet; Celik, Kadir Serdar; Hasan, Mahmood A.; Kilinc, ErsinWater supply from boreholes is today used by people from rural areas of Turkey more commonly due to the reduction of available surface water. For this reason, the concentrations of Al, As, B, Be, Ca, Cd, Co, Cr, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Se, Sn, and Zn in borehole waters of the Diyarbakir province (SE Anatolia) were determined in this study. Thirty borehole waters were sampled from different towns and villages. The samples were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES). The results of the analyses were compared with guidelines as set by Turkey, the WHO, and the EU. From the results it could be concluded that the ICP-OES method can be considered useful for the routine determination of trace elements in waters and similar matrices. For quality control purposes, the certified reference material TMDW-B Drinking Water was employed for validation. The recovery values were in the range of 93-101%. The Al, As, B, Be, Cd, Co, Cr, Hg, Mn, Mo, Ni, Pb, and Sn concentrations in the samples were found lower than the recommended LOD. The concentrations found were in the range of 12.71-111.4 mg/L for Na, 0.76-3.07 mg/L for K, 9.62-115.5 mg/L for Ca, 2.69-41.85 mg/L for Mg, 10 mu g/L.Öğe ICP-OES Multi-element Analysis of Wheat Grown in Southeastern Turkey(Atomic Spectroscopy Press Ltd, 2017) Duz, M. Zahir; Duzgun, Mehmet; Cam, Belgizar; Celik, K. Serdar; Kilinc, ErsinThe bread and durum wheat varieties grown in Southeastern Turkey are the main source of food consumed by the Turkish population and serve as bread and pasta. In this study, 12 kinds of durum wheat and 5 kinds of bread wheat samples registered by the International Agricultural Research and Training Centre of Turkey (IARTC, Turkey) were investigated for their multi-elemental concentrations (Ca, K, Mg, Fe, Zn, Mn, Si, Sn, Cu, Cr, Cd, Ni, V, Pb, As, and Se). The samples were microwave digested and the elements determined by ICP-OES. The results were in good agreement with the certified values. This study shows that the elements Si, Fe, Zn, Cd, Cr, Cu, Sn, and Pb in durum wheat were higher than in bread wheat. Both wheat species were found to be rich in terms of Ca, Mg, and K. The multi-element content of some bread wheat and durum wheat was also in good agreement with the maximum allowable levels of the Food and Agriculture Organization (FAO) World Health (WHO).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 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 Removal of sulfur and ash from coal using molten caustic leaching, a case study from Hazro fields, Turkey(Sage Publications Inc, 2009) Duz, M. Zahir; Saydut, Abdurrahman; Erdogan, Sait; Hamamci, CandanMolten caustic leaching process is effective in reducing significant amount of ash derived from minerals, pyritic sulfur, and organic sulfur from coal. The effect of leaching coal samples from Hazro fields, situated in Southeast Anatolia region of Turkey with molten sodium hydroxide as well as followed by mild acid on demineralization and desulfurization was investigated. The effects of alkali/coal ratio, time, and temperature on the leaching efficiency were detailed and the experimental results are presented here. Chemical demineralization and desulfurization of coal samples using molten sodium hydroxide was investigated in the temperature range of 200-400 degrees C. The percentage of demineralization and desulfurization increased with the increase in alkali/coal ratio. The removal of total sulfur and ash increases with increasing leaching temperature and time. As a result of MCL. ash content of Hazro coal was reduced from 18.31 to 6.77 %, and 70% of combustible was recovered. Total sulfur and volatile matter content was reduced from 7.54 to 1.01% and from 47.80 to 12.41%, respectively. Most of the inorganic sulfur and a significant portion of the organic sulfur were removed.Öğe Separation of liquid fractions obtained from flash pyrolysis of asphaltite(Elsevier, 2008) Saydut, Abdurrahman; Duz, M. Zahir; Tonbul, Yalcin; Baysal, Akin; Hamamci, CandanThe experiments on the flash pyrolysis of asphaltite (Avgamasya, Sirnak, SE Anatolia, Turkey) were carried out in a fixed bed reactor as a basic study. The investigation focused on the effects of pyrolysis temperature and asphaltite particle size on the product distribution and composition. Sample particle size sieve analysis of asphaltite was performed. Liquefaction of asphaltite, different 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 particle size and temperature on conversion and liquid yield was examined. The yield of asphaltite liquid at the condition of -0.60 + 0.25 mm and 550 degrees C at reached a maximum 11.13 wt%. An optimum temperature for the liquid yield was found to be 550 degrees C. The oil product was distilled by fractionally distillation to separate component. The pyrolysis studies provide important quantitative information on the identity, composition and structure of asphaltites. Oil was treated silica gel column chromatography. Using n-hexane, toluene and methanol, the oil was separated into aliphatic, aromatic and polar components, respectively. For further structural analysis, the pyrolysis oils aliphatic, aromatic and polar subfractions were conducted using FTIR. The results of this study provide fundamental data and optimal conditions to maximize light oils yields. (c) 2007 Elsevier B.V. All rights reserved.Öğe Simultaneous Determination of Transition Metals in Hazelnuts (Corylus avellana L.) by ICP-OES(Atomic Spectroscopy Press Ltd, 2014) Celik, K. Serdar; Aydin, Firat; Duz, M. Zahir; Aydin, Isil; Erdogan, Sait; Akba, Osman; Hamamci, CandanHeavy metal concentrations in foods are of interest because of their essential or toxic nature. The present work reports the results obtained for the simultaneous determination of essential and/or toxic metals (Cd, Co, Cr, Cu, Fe, Ni, Pb, Zn) in 24 hazelnut samples by inductively coupled plasma optical emission spectrometry (ICP-OES) after sample digestion using a diluted oxidant mixture in a closed-vessel microwave system. The obtained results (mean in mg/kg) were: Co 1.15, Cr 1.92, Cu 17.96, Fe 489, Ni 4.76, and Zn 85. The concentrations of Cd and Pb were below the detection limits and are below the daily intake recommended by the international organizations (WHO). Therefore, it can be stated that hazelnuts are safe for public consumption. The macro and micro nutrient ranges in hazelnut (Corylus avellana L.) did not exceed the dietary reference intake (DRI).Öğe Simultaneous High-Performance Thin-Layer Chromatographic Determination of Indole Acetic Acid, Indole Butyric Acid, and Absisic Acid in in vitro Seedling of Watermelon Exposed to Heavy Metals(Springer Heidelberg, 2012) Kilinc, Ersin; Okumus, Veysi; Duz, M. Zahir; Aydin, FiratA new method based on the use of high-performance thin-layer chromatography (HPTLC) was developed for the simultaneous determination of the plant growth hormones, indole acetic acid, indole butyric acid, and absisic acid in in vitro seedling of watermelon. The measurements were performed at the associate maximum absorption wavelength of hormones. Calibration plots were constructed in the range of 50-600 ng per spot for indole acetic acid, 50-600 ng per spot for indole butyric acid, and 50-600 ng per spot for absisic acid. The limits of quantification (LOQs) determined experimentally were as follows: 10, 10, and 6 ng per spot, respectively, for indole acetic acid, indole butyric acid, and absisic acid. The method was successfully applied to watermelon tissues exposed to Cu2+, Co2+, and Pb2+ for determination of its indole acetic acid, indole butyric acid, and absisic acid concentrations.Öğe Simultaneous Multielement Determination of Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sn, and Zn in Bulgur Wheat by ICP-OES(Atomic Spectroscopy Press Ltd, 2015) Erdogan, Sait; Aydin, Isil; Duz, M. Zahir; Aydin, Firat; Celik, K. Serdar; Akba, Osman; Hamamci, CandanBulgur is one of the oldest cereal-based foods. This study explains the simultaneous determination by the proposed method for toxic elements such as Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sn, and Zn in bulgur by ICP-OES following digestion in a closed-vessel microwave system. The ICP-OES method is used because it is precise, rapid, simple, and accurate for the determination of 12 metals. The technique can be considered useful for the routine analysis of multi-elements in cereals as well as for quality control purposes. The obtained results in the bulgur samples (mean in mg kg(-1)) were: Al 0.81, Cr 0.19, Cu 3.80, Fe 26.75, Mn 13.60, Ni 0.25, Pb 0.23, Sn 0.17, and Zn 14.30. The concentrations of As, Cd, and Hg were below the detection limits. A certified reference material was used to verify the accuracy of the studied method. The results were in good agreement with the certified values. The toxic metal concentrations are low and the obtained values are suitable for daily intake. The macro and micro nutrient ranges in bulgar wheat did not exceed the dietary reference intake (DRI). The bulgur produced in Turkey has very low levels of toxic metals, is safe for human consumption, and is a highly nutritional and healthy food source. Bulgur wheat is, therefore, safe for public consumption.Öğe Transesterified sesame (Sesamum indicum L.) seed oil as a biodiesel fuel(Elsevier Sci Ltd, 2008) Saydut, Abdurrahman; Duz, M. Zahir; Kaya, Canan; Kafadar, Aylin Beycar; Hamamci, CandanThe sesame (Sesamum indicum L.) oil was extracted from the seeds of the sesame that grows in Diyarbakir, SE Anatolia of Turkey. Sesame seed oil was obtained in 58 wt/wt'Y(,, by traditional solvent extraction. The methylester of sesame (Sesamuni indiculn L.) seed oil was prepared by transesterification of the crude oil. Transesterification shows improvement in fuel properties of sesame seed oil. This study supports the production of biodiesel from sesarne seed oil as a viable alternative to the diesel fuel. (c) 2007 Elsevier Ltd. All rights reserved.
