46
47
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue FLOTATION PRECONCENTRATION OF COBALT AND NICKEL
BY LEAD(II) HEXAMETHYLENEDITHIOCARBAMATE
Gorica Pavlovska, Katarina Cundeva and Trajče Stafilov
Institute of Chemistry, Faculty of Science, Sts. Cyril and Methodius University
P.O. Box 162, 91001 Skopje, Macedonia
Heavy metals have recieved a great deal of attention in the study of water pollution. Nickel and cobalt are ubiquitous trace metals and occur in soil, water, air and in the biosphere. Cobalt and nickel in relatively higher concentrations are toxic elements and can cause different deceases. It is also known that Ni is an allergenic and in some of the compounds a carciogenic element. Therfore, it is very important to know the concentration of these elements in environmental water, which serves for drinking or for irrigation. Atomic adsorption spectrometry is a very sensitive analytical method with low detection limits for many heavy metals (about 0,25 µb/L for Co and Ni). However, in many cases, when the concentration of heavy metals in sample investigating is very low, a direct determination by this method is impossible without any preconcentration. Then, solvent extraction, ion exchange, evaporation and coprecipitation are the most frequently used procedures for preconcentration. In the recent years much attention is paid to preconcentration and separation of heavy metal traces from water matrix by flotation.
The present paper deals with a new flotation method for simultaneous separation of cobalt and nickel traces from fresh water.
Lead(II) hexamethylenedithiocarbamate, Pb(HMDTC)2, was used as a
precipitate flotation collector. It was obtained during the reaction between hexamethyleneammonium hexamethylenedithiocarbamate, HMA-HMDTC, and Pb(II) ions. Mass of Pb, m(Pb), amount of
hexamethylenedithiocarbamate, n(HMDTC-), pH of the system, induction
time, type of surfactants, which are important parameters for the successful flotation, were studied and optimized, After flotation preconcentration, electrothermal atomic absorption spectrometry (ETAAS) was applied for Co and Ni determination. The results obtained by ETAAS were compared with the results obtained by inductively coupled plasma-atomic emission spectrometry. The detection limit of the proposed method is 0,025 µg/L for Co and is 0,0157 µg/L for Ni.
48
ETAAS DETERMINATION OF CADMIUM IN NATURAL
WATER AS IDICATOR OF POLUTION FROM LEAD AND
ZINC SMELTING PLANT
Katarina Cimdeva1, Trajce Stafilov1, Gorica Pavlovska1, Dragica Zendelovuka2 and Vesna Paneva3
1Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Sts. Cyril and Methodius University, Skopje, Macedonia
2Department of Preclinical and Clinical Pharmacology and Toxicology, Faculty of Medicine, Sts. Cyril and Methodius University, Skopje, Macedonia 3Faculty of Mining and Geology, Sts. Cyril and Methodius University, Stip,
Macedonia
Cadmium is a modern toxic metal. It was discovered as element in 1817, but it industrial application was minor until about 60 years ago. Today it is a very important metal with many applications. The main use is electroplating or galvanization due to its noncorrosive properties. It is also used as a colour pigment for paint and plastics, and cathode material for nickel-cadmium batteries. Cadmium is a by-product of zinc and lead mining and smelting plants, which are important sources of environmental pollution. Therefore, the presence of cadmium, even in small concentration in natural waters, which served for drinking or irrigation, might be the sure signal of serious contamination considering the mixing of pure water with contaminated water with cadmium.
This work is an attempt to describe one very fast and very useful method for monitoring cadmium (as well as Pb, Zn, etc.) in the water in the neighborhood of the some zinc and lead smelting plants. A very fast method for separation and preconcentration of cadmium in drinking (source, well, tap) and water for irrigation is described. Iron(III)
hexamethylenedithiocarbamate, Fe(HMDTC)3, has the role of colloid
precipitate flotation collector. The determination of cadmium in final water solutions preconcentrated by flotation (together with two other always following heavy metals, lead and zinc) can be performed by flame (FAAS) or electrothermal atomic absorption spectrometry (ETAAS). The mode of atomization (either FAAS or ETAAS) depends of the concentration level of analyte in the water sample investigating. The AAS results are compared with inductively coupled plasma-atomic emission spectrometric measurements (ICP-AES) as some independent method. The ETAAS detection limit of cadmium is 0.002 µg/L.
49
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue DETERMINATION OF ARSENIC AND THALLIUM IN WINE BY
ETAAS
Julijana Cvetkovic1, Sonja Arpadjan2, Irina Karadjova2 and Trajce Stafilov3
1Institute of Agriculture, Bull. A. Makedonski bb., 1000 Skopje, Macedonia 2Faculty of Chemistry, University of Sofia, Sofia, Bulgaria
3lnstitute of Chemistry, Faculty of Science, Sts. Cyril and Methodius University,
Skopje, Macedonia
Method for the determination of arsenic and thallium in wines by graphite furnace Zeeman atomic absorption spectrometry is described. The possibilities to overcome the strong negative influence of the wine matrix on the atomization of arsenic and thallium have been tested. The action of different types of modifiers on the thermal stabilization of the analytes or on the ensurance of a complete matrix decomposition have been compared. Optimal instrumental parameters as well as the most suitable modifier for direct ETAAS determination of As in wines are presented.
Various sample pretreatment procedures for wine decomposition and preconcentration of arsenic and thallium from red, rose and white wines are investigated. Evaporation of the wine to dryness in presence of oxydizing reagents and liquid-liquid extraction of the analytes into organic phase are the proposed preconcentration procedure. The extraction of arsenic and thallium as chelate complex and as ionic associate into isobutylmethyl ketone is studied. Three modifiers are tested for thermal stabilization of extracted species of arsenic and thallium in the organic phase: palladium as ammonium chloropalladate, silver as silver nitrate and tartaric acid. The concentration of As and Tl in commercial wines from Macedonia and Bulgaria have been presented.
50
SPECIATION AND ETAAS DETERMINATION OF Cr(III) AND Cr(VI) IN TEXTILE MATERIALS
Irina Karadjova, Sonja Arpadjan
Faculty of Chemistry, University of Sofia, bul. J. Bourchier 1, 1126 Sofia, Bulgaria.
Liquid-liquid extraction and column solid-phase extraction procedures have been compared for speciation and ETAAS analysis of chromium in textile materials. Liquid-liquid extraction of ion associates of Cr(VI) with long chair quaternary
ammonium salts and extraction of chelate complex of Cr(VI) with ammoniumpyrrolidinedithiocarmate was investigated for separation of Cr(VI) from Cr(III) in the presence of different reagents used in the sample preparation procedures.
Column solid phase extraction procedure was performed by using ammonium hexametylenedithiocarbamate or trioctylmethylammonum chloride physically immobilized on polyuretane foam, silicagel or filter paper and disposable syringes as microcolumns. MIBK or 3M nitric acid were tested for the elution of Cr(VI). Optimal conditions and recoveries obtained for the separation and preconcentartion of Cr (VI) in the presence of various chemical reagents are presented.
The redox equilibrium between Cr(III) and Cr(VI) is sensitive to pH changes and to addition of oxidizing or reducing agents. Therefore the leaching of chromium species from sample matrix is as important step as their reliable separation and determination steps. Spike experiments were performed with various chemical reagents for quantitative extraction of Cr(III) and Cr (VI) from textile materials treated with different dyes: 1M HCL, 1M CH3COOH, 1M acetate buffer (pH 5.7) and redistilled water at room temperature and at 90 °C under reflux. Fast reduction (less than 30 min) of Cr(VI) to Cr(III) was observed in acidic media so further speciation experiments were performed after leaching of chromium in redistilled water. The most suitable analytical procedure for separation and preconcentartion of Cr(VI) in textile materials from the view point of reproducibility, repeatability, detections limits achieved and analysis duration is proposed on the basis of the results obtained.
51
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue INVESTIGATIONS ON THE THERMAL BEHAVIOUR OF VARIOUS LEAD SPECIES IN ELECTROTHERMAL ATOMIC ABSORPTION ANALYSES OF SULFUR CONTAINING MATRICES
Sonja Arpadjan, Irina Karadjova
Faculty of Chemistry, University of Sofia, bul. J. Bourchier 1, 1126 Sofia, Bulgaria
The thermal behaviour of lead species (lead nitrate, lead cyclohexabutyrate, tetraethyllead) in inorganic sulfur containing salts (ammonium, sodium and potasium – sulfate, sulfite, sulfide, thiosulfate, pyrosulfate, peroxodisulfate) and in organic sulfur containing matrices (sodium diethyldithiocarbamate, ammonium pyrrrolidinedithiocarbamate, thioacetamide and thiourea) have been investigated in details. A remarcable differences were observed in the pretreatment and atomization behaviour of lead in the case of the ammonium inorganic salts and in the same kind sodium and potasium salts. The role of the sodium and potasium ions as well as of the anionic part of the salts on the recorded lead atomic absorbtion signal is discussed. The possibilities of different modifiers to uniform the thermal behaviour of lead independent on the salt type will be tested.
It was found that all investigated organic sulfur containing matrices act as organic chemical modifier for lead. The studied organic sulfur matrices stabilize Pb up to 800 oC pretreatment temperature and require relatively low (1400 oC) atomization temperature. It can be concluded, that the presence of sulfur in the studied organics has no influece on the pretreatment and atomization behaviour of lead.
The developed optimal temperature programs were applied to determination of Pb in foods and beverages and in high purity chemical reagents.
52
DETERMINATION OF COBALT, COPPER, LEAD AND NICKEL IN GYPSUM
BY ZEEMAN ELECTROTHERMAL ATOMIC ABSORPTION
SPECTROMETRY
Dragica Zendelovska1, Trajče Stafilov2 and Bora Ristova3
1 Institute of Preclinical and Pharmacology and Toxicology, Faculty of Medicine, Sts. Cyril and Methodius University, 50 Divizija, Skopje,
Macedonia
2 Institute of Chemistry, Faculty of Science, Sts. Cyril and Methodius University,
POB 162, 91000 Skopje, Macedonia 3 PRMB Bučim, Radoviš, Macedonia
A rapid method was developed for the extraction of cobalt, copper, lead and nickel from dissolved mineral samples by sodium diethildithiocarbamate into methylisobutyl ketone and their determination by Zeeman electrothermal atomic absorption spectrometry. The matrix interferences were investigated and results show that Ca (as matrix element) tends to decrease absorbance of investigeted elements. Therefore, a separation of Co, Cu, Pb and Ni from the solution obtained by dissolution of gypsum in HCl was suggested. Standart addition technique was used for the evaluation of data and method was tested using certified reference materials. The standart deviation (s) is 4 ng.g-1 for Co, 17 ng.g-1 for Cu, 8 ng.g-1 for Pb and 7 ng.g-1 for Ni. The detection limit of the method, calculated as 3s of the blank, was found to be 12 ng.g-1 Co, 51 ng.g-1 for Cu, 24 ng.g-1 for Pb and 21 ng.g-1 for Ni.
53
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue DETERMINATION OF SOME METAL IONS BY AAS IN BAKING
POWDER AND BAKING SODA SAMPLES AFTER PRECONCENTRATION AND SEPARATION
S. Saraçoğlu1, Ü. Divrikli1, M. Soylak1, F. Armagan2,L. Elçi3
1Erciyes University, Faculty of Art and Science, Dept. of Chemistry, Kayseri-TURKEY
2Erciyes University, Yozgat Fac. of Art Science, Dept. of Chemistry, Yozgat-TURKEY
3Pamukkale University, Fac. of Art and Science, Dept. of Chemistry, Denizli-TURKEY
Atomic absorption spectrometric determination of trace heavy metal ions in various saline samples including dialysis solution, urine, mineral waters table salts etc. is an important part of analytical chemistry. In this determinations effects of the matrix and low metal concentrations are two main problems. These problems are generally prevented by using various separation/enrichment techniques such as solvent extraction, ion exchange, copreciptation and solid phase extraction [1-4].
In this work, the contents of some metal ions of baking powder and baking soda samples have been determined by atomic absorption spectrometry after separation and preconcentration. Two different separation/preconcentration techniques including APDC-Chromsorb 102 solid phase extraction technique and Ce(OH)4 coprecipitation technique have been used for this purpose. The effects of the contents of the baking soda and powder were examined. The methods were applied for the determinations of Cu, Fe, Pb, Bi and Ni in the baking soda and baking powder samples purchased from the local markets in Kayseri City-Turkey. The results found for metal ions both technique are agree each other.
References
[1] M. Soylak, Fresen. Environ. Bull., 7, 383-387 (1998). [2] L. Elçi, S. Saraçoğlu, Talanta, 45, 1305-1310 (1998).
[3] M. Soylak, Ü. Divrikli, L. Elçi, M. Doğan, Kuwait J. Sci. Eng., 25, 389-396 (1998).
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COMPARISON OF WET MICROWAVE DIGESTION METHODS OF PLANT MATERIALS AND FAAS DETERMINATION
S. J. Walas, M. Wojtowicz
Walas@chemia.uj.edu.pl
Jagiellonian University, Faculty of Chemistry Ingardena 3, 30-060 Krakow, Poland
Phone: + 48 12 – 6336377 ext. 2232, fax: + 48 12 – 6340515
Flame atomic absorption spectrometry (FAAS) has for many years been used in the analysis of various materials, including plant samples. For wet mineralization of plant materials many digestion procedures and acid compositions have been proposed and nowadays adopted to microwave technique. In the most cases they are designed for optimal transferring of subsequent element into solution. Therefore in the multielement analysis the fundemental question is which one should be selected.
Mineralization effectiveness and transferring into solution of Ca ( one of main compent), of Mg and Fe (minor constituents) and of Cu and Zn (trace elements) from tobacco sample using ten procedures and close microwave system, were tested searching for universal optimal one.
Procedure Mixture of reagents [ml] Delay time [h]
Mineralization
time [min]* pressure Max.
[atm] I 6 HNO3 0 30 45 II 6 HNO3 + 1 HF 0 30 45 III 6 HNO3 + 2 H2O2 0,5 30 45 IV 6 HNO3 + 1 HClO4 0,5 30 45 V 1,5 HNO3 + 4,5 HCl 1 30 45 VI 6 HNO3 + 1 H2O2 1 30 45 VII 1,5 HNO3 + 4,5 HCl 24 30 45
VIII 6 HNO3 + 1,5 HClO4 + 1,5 HCl
after mineralization
1,5 30 45
IX 4,5 HNO3 + 1,5 HCl 1,5 30 45
X 6 HNO3 + 1 HClO4 1,5 30 45
* Total mineralization time included three stages of different
microwave power: 60 (5 min.), 85 (5 min) and 100 % (10 min.), respectively and 10 minutes cooling time.
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In the first step efficiency of analytes extraction and relative standart deviation were criteria of asessment. Thereafter procedures VII, VIII and IX, of the best opportunity, were chosen for detailed investigation, including accuracy. The final examination was carried out using tobacco “Virginia” Standarts Reference Material CTA-OTL-1, poland.
For all analyses standart conditions of FAAS determination were applied, but for the addition of ionisation buffer was necessary. Comparison of accuracy and pecision shows, that the most universal and reliable is IX procedure.
Results of analytes transition into solution and precision of repeatability will be presented for all tested procedure as well as, comparing adequate certificate values of SRM, accuracy for VII, VIII and IX.
56
DETERMINATION OF ARSENIC IN İZMİR BAY SEDIMENTS BY ATOMIC
ABSORPTION SPECTROMETRY WITH THE HYDRIDE GENERATION
TECHNIQUE
E. Henden, N. E. Yücetürk, A. Erdem, F. Yiğit
Department of Chemistry, Faculty of Science, Ege University, İzmir-Turkey
nerdem@fenfak.ege.edu.tr
For many years, İzmir Bay has been a suitable place for sea animals and plants by its geologic, morphologic, and biologic characteristics. In the last 40 years, because of the increase in the population of İzmir city which is surrounding the İzmir Bay and the industries around the pollution in the bay increased exponentially.
The aim of this study is to determine the arsenic content of İzmir Bay sediments and to discuss its harmful effects on environment.
The sediment samples were collected from twenty different station in 1996 and 2000. The samples were decomposed using HNO3 + H2O2 wet digestion method. Arsenic analyses in the collected sediment samples were performed using atomic absorption spectrometry with the hydride generation technique. Finally, arsenic concentrations of the sediment samples collected in 1996 and 2000 were compared. The results showed that the environmental pollution increased between 1996 and 2000.
57
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue DETERMINATION OF MERCURY AND ARSENIC IN TABLE SALT
E. Henden, F. Yetiş, N. E. Yücetürk, A. Güray
Dept. of Chemistry, Faculty of Science, Ege University, İzmir-Turkey
fyetis@fenfak.ege.edu.tr
Mercury and arsenic are well known toxic elements and their toxicity to humans has been well established. Therefore, there is a need for fast, reliable and accurate methods for determination of mercury and arsenic. The most sensitive techniques in literature depends on atomic fluorescence measurements for mercury determination and atomic absorption spectrometry with the hydride generation technique for arsenic detection. Study of the applicability of these techniques to table salt samples is thought to be of great value.
In our study, we have collected unrefined salt samples from Çamaltı Saltpan near by İzmir Bay and refined salt samples belonging to different commercial firms. The salt samples were digested with classic wet ashing method using HNO3+H2O2. The results were below of upper limit values.
58
ELIMINATION OF INTERFERENCES AT THE QUARTZ TUBE ATOMIZER IN
THE DETERMINATION OF ARSENIC AND ANTIMONY BY HYDRIDE
GENERATION ATOMIC ABSORPTION SPECTROMETRY
E. Henden, N. E. Yücetürk
Department of Chemistry, Faculty of Science, Ege University, İzmir-Turkey,
nerdem@fenfak.ege.edu.tr
Atomic absorption spectrometry using the hydride generation technique and a quartz tube atomizer provides a very sensitive technique for arsenic and antimony determination. One of the main advantages of this technique is that the hydride-forming elements are separated from the matrix elements present in the sample solution. However, several cations interfere with these determinations. It appears that interferences take place both at the hydride generation step in the reaction vessel in aqueous phase and at the atomization step in the atomizer.
In this study, mutual interference arsenic and antimony on each other during the hydride generation atomic absorption spectrometric determination of arsenic and antimony were examined using a quartz tube atomizer. In order to eliminate or reduce interferences, different methods have been studied. These includes, using adsorption tube containing interfering metal coated pumice or glass wool before the atomizer, supplying oxygen into the quartz tube during atomization.
59
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue AIR POLLUTlON CONTROL VIA PRECIPITATlON ANALYSIS IN
IZMIR
R.Esra DEMIRDOGEN, Türker PASİNLİ, Emür HENDEN
Precipitation was collected in four different sites; Karabağlar, Hatay, Altındağ and Karşıyaka, for to monitor the spatial and temporal changes of pollutants over City of İzmir. Rain water samples collected via new simple and efficient bench-ytpe collectors during December 1999 – May 2000 were analyzed and characretized regarding their acidity, conduvtivity, trace metal components: As, Hg, Zn and Cu; and earth alements: Na, K, Ca. Dependent on the changes of emission of pollutants resulting from various industries (i.e., petro-chemical ind., reformation ind.), the decrease of stock-farming and increase of traffic characteristic changes in the above mentioned parameters under investigation could be observed.
60
INVESTIGATION OF POLLUTION LEVEL IN KARAKAYA DAM LAKE
F. Zehra KUCUKBAY
Inonu University, Faculty of Arts and Sciences, Department of Chemistry, 44069
Malatya-TURKEY
Industrialization and domestic effluents or sewage have become rather effective in polluting aquatic environments. Aquatic environments are affected primarily leading to serious problems for the fish and other organisms.
In this study, some chemical, physical and biological properties of the dam lake were determined seasonally in 1999. Measurements of dissolved oxygen, pH, conductivity and beat of the dam lake were done in situ by using filed type instruments.
Water and sediment samples obtained from four different sites were analyzed in laboratory. Total filterable residue of the water samples were determined by using 0.45 µm membrane filter. Chemical oxygen demand (COD), biological oxygen demand (BOD), Fe, Cu, Pb, Mn, Cd, Ca, Na, Cl2, phosphate, nitrite nitrogen, ammonia nitrogen, organic matter levels of the dam lake and Fe, Cu, Mn, Pb, Cd, rot, Na of the dam lake’s sediments were determined using by HACH model DR/2010 spectrophotometer.
The detailed experimental procedures and the results obtained will be presented.
This work has been supported by the mono University research fund
through grant IUAF-98/42
61
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue SAMPLING AND ANALYSIS OF POLYCYCLIC AROMATIC
HYDROCARBONS (PAHs) FROM AMBIENT AIR
Yrd. Doç. Dr. Nedim Vardar
Balıkesir Üniversitesi, Mühendislik – Mimarlık Fakültesi Çevre Mühendisliği Bölümü, 10100 Balıkesir.
Polycyclic (or polynuclear) aromatic hydrocarbons (PAHs) have recieved increased attention in studies of air pollution in recent years because some of them are highly carcinogenic or mutajenic. In order to understand the atmospheric fate and transport of PAHs, it is desirable to measure their concentrations both in the gas and particulate phases. However, PAHs in ambient air can not be measured directly, because the,ir concentrations are so low. These low concentrations complicate the process of obtaining a sample for analysis. Sampling the low but extremely important levels of PAHs in ambient air generally requires passing hundreds of cubic meters of air through a filter and sorbent system.
Several different sampling and analytical methods have been used to obtain the ambient air concentrations of PAHs both in the gas and particulate phases. In this study, sampling and analytical methods commonly used for PAH compounds are summarized. The sampling and analytical procedures applied for the samples collected from ambient air of Chicago are presented. The advantages of the entire procedure, from sample collection to chromatographic analysis, are presented. The problems of determining the distribution of PAHs in the atmosphere between the gas and particulate phases is also discussed.
62
DETERMINATION OF SELENIUM BY SPECTROPHOTOMETRIC AND VOLTAMMETRIC METHODS
M.Haluk TÜRKDEMİR and Sema B. ERDEMOĞLU
İnönü University, Arts&Science Faculty, Chemistry. Dept. 44069 Malatya/TURKEY
Selenium is an essential component of glutathione peroxidase and other enzyme systems and is therefore essential for animal metabolism. It is, however, toxic at concentrations little above those required for health. To date, the major functions of selenium can be attributed to its antioxidative properties and its role in the regulation of thyroid hormone metabolism, cell growth and eicosanoid biosynthesis1. Both organic and inorganic forms of selenium may be utilised by the body, with the selenoamino acids showing greatest bioavailability.
Nowadays more attention has been paid to the role of selenium in biological system and hence the determination of this element has attracted much importance. Because of vital role of selenium in biological systems, developed many sensitive analytical techniques for the determination of this
element2. In this work we compared a spectrophotometric method and
anodic stripping method on a Hg-film electrode in respect of detection limit and sensitivity for selenium.
[1] Patching S.G., Gardiner PHE, J. Trace Elements in Med. And Biol.1999, 13(4), 193.
63
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue LEACHING OF ALUMINIUM FROM COOKING UTENSILS
Mehmet Güneş, Sezgin Bakırdere and Mehmet Yaman
Firat University, Sciences and Arts Fac.Department of Chemistry-Elazig 23119/Turkey
myaman@firat.edu.tr
0532-3059845 Fax: 0424-2330062
Interest in the potential link between high aluminium contents in tissues and various neurodegenerative disorders such as Alzheimer’s disease has drawn attention to the intake of aluminium from food, drinking water, parenteral nutrition or dialysis fluids in individuals with chronic renal disease. The important sources of Al intake for human are food and particularly the aluminum cooking utensils. In our previous work, the Al contents of milk and fruit juices were determined by using enrichment procedure and flame atomic absorption spectrometry (FAAS) (1).
In this study, aluminium concentrations in Turkish meal by using different cooking utensils are determined by FAAS. It is obtained that the Al concentrations in meals are increasing when the old cooking utensils are used.
UV/VIS STUDY OF THE REACTION OF INDOLE
WITH NITRITE IONS IN HYDROCHLORIC ACID SOLUTIONS
B. S. Andonovski and G. M. Stojkovic
Institute of Chemistry, Faculty of Natural Sciences and Mathematics “St. Cyril and Methodius” University, P.O. Box 162,1001 Skopje,
Macedonia
Phone:+++389 91/117-055 Fax: +++ 38991/228-141 E-mail: b1agand@iunona.pmf.ukim.edu.mk
UV/ViS spectroscopy can be used to study many types of chemical process, for example acid-base equilibria, addition reaction or redox equilibria. Quantitative determination of indole (or nitrite ions) are intensively because their possible involvement in polluted waters. Nitrite ions in potable water can be induced methemoglobinemia or formed carcinogenic nitroso indoles (or amines and amides).
The present work is a investigation of spectrophotometric method for indole (or nitrite ions). A single nitrosation reaction (addition of NO to indole), followed by acidic catalyzed condensation of initially formed product (II) treatment is described for indole.
N H N H H NO N H NOH N H N H NOH N H NO
The effects of the independent variation of concentration of h3drochloric acid solutions from 0.01 to 2.0 mol dm-3 or nitrite ions from 1.0.l0-5 mol dm-3 to 3.0 l0-3 mol dm-3 upon indole were investigated with respect to the absorption spectra and stability of the reaction products. Nitrite ions in hydrochloric acid solutions of indole introduces a strong chromophoric group in the aromatic molecule. Indole was subject to
65
nitrosation reaction at 300C for 5, 10, 15, 20, 25 and 30 min.
Acidic solutions of nitrosation products exhibits maximum absorption (broad bond) at 500-530 nm and a second maximum of 400 - 450 nm. The Job-method, molar ratio method and the method of relative recovery of products species was found that stechiometric ratio between indole ad nitrite ion is 2:1.
66
RAPİD SPECTROPHOTOMETRIC METHOD to RESOLVE TERNARY
MIXTURES of SUNSET YELLOW, TARTRAZ1NE and BEETROOD RED in
POWDER DRINKS
G. A1pdoğan, M. Üstün Özgür
Yıldız Technical University, Faculty of Science and Arts , Department of Chemistry S0270 , Şişli - İstanbul / TURKEY, E -mail: galp @
yildiz.edu.tr.
Over 50 synthetic dyes are used in foods all over the world [1]. In Turkey eleven dyes are permitted for use in food. However, unlawful dyes are also frequently detected in food [2], so the inspection of dyes in foods has been continued by public health agencies. As a results, the analysis of dyes in food is very important.
Derivative spectrophotometry , particularly with digital processing, is an analytical
technique of great utility for resolving some mixtures with overlapping spectra.
In this work, a very simple spectrophotometric method is described for resolving ternary mixtures of the food dyes sunset yellow (E-110), tartrazine (E-102) and beetrood red (E-162) by using the first and second derivative of the spectra with measurements at zero-crossing wavelengths.
The assay procedure for E-110, E-102 and E-162 in powder drink involves extraction of the dyes from powder drink with distilled water and measurement first derivative absorbance values at 535.6 nm for E-110, 575.7 nm for 162 and second derivative absorbance value at 494.0 nm nm for E-102.
Linear correlations over the concentration ranges of 200-1000 mg / L for l62 (r=0.9991), 6-30 mg / L for 102 (r=0.9994) and 4-20 mg / L for E-110 (r =0.9996 ) were obtained.
Repeatability and reproducibility studies (with the students’s and F tests were achieved for two series of nine standarts for each dye showing no significant differences at the 95 % confidence level.
This method was satisfactorily used for determining synthetic mixtures of these colorants in different ratios and it was successfully applied to a
67
commercial product containing the three dyes ; no separation step is required. The results were compared with those obtained by liquid chromatography and very similar values were found by both methods.
References
[1] Standard Methods of Analysis of Hygienic Chemists with Commentary Authorized by the Pharmaceutical Society of Japan, Kinbara, Tokyo, p.500 (1990).
[2] Port Quarantine Stations, Ministry of Health and Welfare, Imported Foods 1991, Japan Food Hygiene Association, Tokyo, p. 145 (1992).
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SPECTROFLOURIMETRIC DETERMINATION OF SELENIUM BY 3,3’-DIAMINOBENZIDINE IN SERUM OF CHILDREN WITH
ANEMIA
Ali ÖLÇÜCÜ and Sinan SAYDAM
Fırat University, Faculty of Arts and Science, Department of Chemistry, 23169 Elazığ.
The analysis of selenium, which is a trace element required for living organisms, by spectroscopic methods is difficult due to having various oxidation steps, showing evaporation in low temperature, and trace amount of selenium existence in biological materials. Spectroflourimetric method in the determination of selenium in body fluids is one of the best methods used to get accurate and repeatable results1.
In this study, the Se(IV)-3,3’-diaminobenzidine (DAB) complex was first formed in an aquatic medium. The analysis conditions were optimised by characterising all analytical parameters such as maximum wavelength, time, pH, extractor, extraction pH and step, interference, and linear working range for Se(IV)-DAB complex. The detection limit for selenium was found to be 20 µg L-1.
The blood serum samples, provided pediatry department of Fırat University Research Hospital, of healthy children (control group) and with anemia diseases children caused by iron deficiency of 0-15 age groups, in Elazığ region have been investigated. The pre-specified volumes of serum
samples were prepared by microwave digestion process in HNO3, HCIO4
and H2O2 mixtures of specified ratios under high pressure (in Teflon bomb). The ions causing interference were investigated and eliminated. The Perkin-ELMER 100 model spectroflourimeter was used in analysis of serum samples.
It was obtained that there is an important difference between the serum selenium levels of control and patient groups (p<0.001). The obtained results are shown in the following table.
Groups Number of Samples (n) µg Se L-1serum
Control 37 53.85±7.99
Patient 44 32.65±6.61
References
69
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue FOURIER TRANSFORM INFRARED (FTIR) SPECTROSCOPY FOR MONITORING AND DETERMINING THE CRYSTALLISATION OF
POLYHYDROXYALKANOATES (PHAS)
Mustafa Kansiza,b, Gerhard Schrollc, Alexander Kainzc, K. Christian Schustera, Don McNaughtonb and Bernhard Lendla*
a Institute of Analytical Chemistry, Vienna University of Technology, Getreidemarkt 9/151, A-1060, Vienna, AUSTRIA
b Department of Chemistry, Monash University, Wellington Rd, Clayton, Melbourne, VIC, 3168, AUSTRALIA
c Institute of Microbiology and Genetics, University of Vienna, Dr Bohr Gasse 9, A-1030 Vienna, AUSTRIA
Many prokaryotic organisms synthesis biodegradable thermoplastics belonging to the Polyhydroxyalkanoate (PHA) group of biopolymers. These polymers are accumulated as intracellular granules for use as carbon and energy reserves. The most common example of this group is poly(β-hydroxybutyrate) (PHB). Although PHB is a rather brittle and thermally unstable polymer, the copolymer poly(hydroxybutyrate-co-hydroxyvalerate) (PHB-co-HV), which is the one most widely used, has similar mechanical and thermal properties to polyolefins, such as polypropylene and polypropylene.
Because of the fact that these polymers biodegrade to harmless metabolites, they have gained interest not only as a replacement to the environmentally unfriendly and petrochemically derived polyolefins, but also as slow release drug carriers and in other medical applications.
Pure PHB is a highly crystalline polymer, which makes it unsuitable for in-vivo applications, as the enzymes that degrade these polymers, do not work as efficiently as they do for the polymer in its amorphous state. Therefore the challenge from the microbiological and genetic point of view, is how to produces and isolate these polymers in a pure enough fashion that they remain as amorphous as possible. Proteins and lipids that surround the granules and the methods of extraction and purification of the granules from the cells, have all been shown to effect the degree of crystallinity. Now the challenge from the analytical point of view is to develop a new method the is able to determine the degree of crystallinity and perhaps also to be able to follow the crystallisation kinetics. Currently, methods such as X-ray powder diffraction and Nuclear Magnetic Resonance (NMR) are used. However,
opposed to D2O), and the instruments can be very expensive and not readily available.
Initial results using FTIR spectroscopy have shown that this technique is extremely sensitive to changes in the crystallinity. Such changes are mostly reflected in an apparent shift in the ester carbonyl band position
of the PHAs (1744 – 1722 cm-1). However, upon the calculation of the
second derivative of the spectra, it can be seen that there are in fact two overlapping bands contributing to the ester carbonyl absorbance. From comparisons to the spectra of a highly crystalline PHB standard, and spectra of PHA granules containing some proteins (which are more amorphous), we
postulate that the these bands at ~ 1744 and ~ 1722 cm-1 are from the
amorphous and crystalline phases respectively. Therefore we propose a novel method for the determination of the degree of crystallinity by the ratio of the intensities of these two bands.
Fig.1 shows the second derivative ester carbonyl band of pure highly crystalline PHB. Fig. 2, shows the presence of two bands, an amorphous and a crystalline band. The ratios are seen to change over time as the sample slowly cyrstallises, with the crystalline band increasing as the amorphous band decreases.
These preliminary results, show the potential of FTIR spectroscopy as a novel method for the monitoring and determination of crystallinity in varied samples containing PHAs
Pure cyrstalline PHB 1780 1760 1740 1720 1700 1680 0 -0.2 -0.4 -0.6 -0.8 0.2 Wavenumber (cm-1) A rb it ar y U ni ts Pure cyrstalline PHB 1780 1760 1740 1720 1700 1680 0 -0.2 -0.4 -0.6 -0.8 0.2 Wavenumber (cm-1) A rb it ar y U ni ts
70
Fig 1. Second derivative spectrum showing the
ester carbonyl absorbance of pure highly crystalline PHB
amorphous band 1780 1760 1740 1720 1700 1680 0 -0.4 -0.6 -0.8 -1.0 0.2 Wavenumber (cm-1) A rb it ar y U ni ts -0.2 0.4 0.6 crystalline band amorphous band 1780 1760 1740 1720 1700 1680 0 -0.4 -0.6 -0.8 -1.0 0.2 Wavenumber (cm-1) A rb it ar y U ni ts -0.2 0.4 0.6 crystalline band
Fig 2. Second derivative spectrum
showing the ester carbonyl absorbance of a granules. Note the changes in absorbances, indicative of crystallisation
72
INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS OF SOME MINERALS FROM ALLCHAR MINE
Anna Lazaru1, Radojko Jacimovic, Radomir Ilic2 and Trajcc Stafilov3
1Ministry of Interior Affairs, Criminological Laboratory, Skopje, Macedonia 2jozef Stefan Institute, Jamova 39, 1001 Ljubljana, Slovenia
3lnstitute of Chemistry, Faculty of Science, Sb. Cyril and Methodius University,
POB 162, Skopje, Macedonia
The investigation reported in this paper is a part of the LOREX project, determined to measure the solar neutrino flux using thallium minerals from Allchar mine, Republic of Macedonia. Mineral samples of lorandite (T1AsS2), markasite (FeS2) and dolomite (CaMg(CO3)2) taken from this mine, were irradiated with thermal neutrons in TRIGA Mark II reactor of the “Jozef Stefan” Institute in Ljubljana, Slovenia. The high concentrations of matrix elements influence on the determination on the some trace element contents. The results are discussed and compared by those obtained by other methods [1-5]. The low uranium and lead content in minerals make possible the using of lorandite as solar neutrino detector. [1] A. Lazaru, T. Stafllov, Geologica Macedonica, 7,73 (1993).
[2] T. Stafilov, A. Lazaru, E. Pernicka, At. Spectrosc., 16,158 (1995). [3] A. Lazaru, T. Stafilov, Anal. Lab., 6, 101 (1997).
[4] A. Lazaru, T. Stafilov, Fresenius’ J. Anal Chem., 360,726(1998).
[5] A. Lazaru, R. Ilic, J. Skvarc, E. S. Kristof, T. Stafilov, Radiation
73
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue FLOW INJECTION ON-LINE SORPTION
PRECONCENTRATION ICP-AES - HEAVY METALS DETERMINATION IN SALTS AND BRINES
Nataliya Goulko1, Evelina Sedykh1 and Tamara Tchemleva2
1 Vernadsky Institute of Geochemistry and Analytical Chemistry, 19 Kosygin St., 117334 Moscow, Russia
2 Lomonosov Moscow State University, 119899 Moscow, Russia
Flow injection on-line sorption preconcentration ICP-AES has been used for the development of new sensitive and selective methods of heavy metals determination in the brines and salts.
Determination of Cd, Zn, Pb, Co, Cu, Ni, Mn, Fe, V, Ti, Ba, Al in saline matrix is necessary for geology, geochemistry, salt industry and ecology (pollution by industrial waste). The analytical problems arises from high salts concentration (NaCl, KCl, CaCl2, MgCl2, ~200g/l) that results in high viscosity and high background emission in ICP-AES. On-line multielement preconcentration with separation of matrix is an effective solution of this problem.
The instrumental system being developed consists of the ICP - AES polychromator Jarrell Ash ICAP 9000, installed on-line device for flow injection sorption preconcentration BPI - 01 (Cortec, Russia), micro column packed with DETATA sorbent (aminocarboxylic). FI - ICP-AES system was fully automated.
There are many factors that influence effective FI preconcentration: content of salts, sorption and desorption flow rates, sorption and desorption times (ore volumes of the sample and eluent), pH, acid concentration in eluent, kind of eluent, etс. Therefore, fractionary factorial design was used to obtain an adequate sensitivity and also to optimize the emission signal of ICP. The orthogonal designs have been used, recovery, equivalent volume, emission signal, enhancement factor has been chosen as dependent variable. The investigation of recovery was carried out in off-line mode. The second order design for two independent variables has been realized. The regression functions describing the investigated systems have been calculated and optimal conditions have been estimated. For example, twin correlation between eluent concentration (HNO3) and eluent flow rate for Co can be represented by the following equation: (Y - the emission signal)
74
3.7474 X1X2
The proposed method is the fast and effective tool for the investigation of sorbents and developments of the analytical procedures. The parameters of simultaneous multi-element sorption, elution, and signal registration have been optimized. The parameters of flow sorption ICP – AES analysis of the samples with complex matrices were investigated and the analytical procedure for simultaneous determination of Cd, Zn, Pb, Co, Cu, Ni, Mn, Fe, V, Ti, Ba, Al in industrial brines and salts was developed. The enhancement factors achived after concentration for 1 min are 23 (Cu), 16 (Cd, Zn), 21 (Co), 11 (Cr, Mn, Pb) and 10 (Fe, Ni, V). The detection limits are 10 –20 times better in comparison with conventional ICP – AES. RSD of different elements are 2 – 6 % for 10 – 100 µg ml-1 concentration ranges.
75
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue RESOLUTION OF OVERLAPPED PEAKS WITH EVOLUTIONARY
GENETIC ALGORITHM BASED ON STOCHASTIC SEARCH PROCEDURE
Mustafa Karakaplan
İnönü University, Arts&Science Faculty, Chemistry Department, 44069 Malatya/TURKEY
mkarakaplan@inonu.edu.tr
A global search technique for curve fitting based on evolutionary random search was modified and applied for peak quantifying a combination of gaussian and lorentzian peaks. This stochastic search procedures based on randomized operators, a modified Monte Carlo method. The method tested on self obtained several overlapped lorentzian peaks with random noise, lennard particles in three dimensions, discrete mathematical functions previously used for optimization in literature and some experimental data.
This method is suitable for complex, large scale optimization. The results of the new method have been compared with those obtained by a commercial peak fitting programs. This method gives better results and also computationally fast.
76
DETERMINATION OF SOME HEAVY METALS IN SAKARYA RIVER AND SOILS IRRIGATED BY SAKARYA RIVER
Mustafa S. DUNDAR♣, Mustafa IMAMOGLU*, Huseyin ALTUNDAGΨ
Sakarya University, Fen-Edebiyat Fakültesi, Kimya Bölümü, Mithatpaşa-54100 Adapazarı / TURKEY
♣E-mail:dundar@sakarya.edu.tr * E-mail:imamoglu@sakarya.edu.tr Ψ E-mail:altundag@sakarya.edu.tr
In last decade, as the environmental pollution is increased the importance of monitoring and determination of some heavy metals become more important for the analytical scientists. Heavy metal contents in the environmental samples such as soils, natural waters, plants etc. have been determined continuously in the various areas. In this work, samples from Sakarya river and soils irrigated by Sakarya river collected from Karasu, Ferizli, Adapazari, Geyve and Osmaneli regions. Lead, Copper, Chromium, Zinc, Nickel and Cadmium concentrations of Sakarya river and soils irrigated by Sakarya river were determined by Flame Atomic Aabsorption Spectrometer. In addition, collected soil samples irrigated by Sakarya river
were solved by HCl/HNO3 mixture and the heavy metal contents were
77
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue MEASUREMENT OF CADMIUM CONTENTS IN AIR OF SOME
INDUSTRIAL ROOMS AFTER ELECTROSTATIC PRECIPITATION ON THE GRAPHITE TUBE
E. Altman*, I.Grinstein, L.Vasilieva**
* “Analyt Ltd “ ,197198 , St.-Petersburg, Russia, E-mail:altman@ea4603.spb.edu
** “Russian Scientific Center Applied Chemistry, 197198,St.-Petersburg
E-mail:grin@an.apchem.spb.su
Cadmium is an object of global environmental monitoring program of United Nations along with Pb and Hg.It is well known that Cd as a chemical element causes cancer. Using of the possibilities of ( EP-GF – AAS) device for electrostatic precipitation directly on Graphite Furnace (GF) for Atomic Absorption Spectrometry operating in near-real time we have estimated the contents of Cadmium ( as a metal) in the air of some industrial rooms(1). For this purpose were taken the samples of air from some rooms (analytical laboratory and library) with natural ventilation.The volumes of investigated rooms varied from 150 to 200 m3. Air was sampled directly in GF situated in portable EP-device. The air flow rate was (7±0,5)l\min and sampling time are in the table.
Determination of Cd contents in air
Sample Abs. BG Time of pumping, min
1 0.0430 0.0205 2 2 0.0465 0.0054 2 3 0.1683 0.0343 8 4 0.1216 0.0157 8 5 0.0865 0.0199 4 STD 1ppb 0.0766 0.0012 -
All the measurements of cadmium contents were carried with Shimadzu 6800 atomic absorption spectrophotometer.This system is very convinient for such experiments due to a high sensitivity provided by GFA-EX7 electrothermal atomiser with digital control. Cadmium contents in the air of the analytical laboratory is within the limits 0,86÷1,0 ng/m3 and in the air of library it is 0,46 ng/m3
Reference:
[1] E.L. Altman and N.A. Panichev, Canadian Journal of Analytical Sciences and Spectroscopy,42,62(1997)
78
INVESTIGATION OF PHOTOCHEMICAL DEGRADATION PRODUCTS OF SOME TEXTILE DYES BY UV-VIS DERIVATIVE
AND CHEMOMETRIC METHODS
Neslihan Altun, Cevdet Demir, Şeref Güçer
Uludag University, Faculty of Science and Arts, Department of Chemistry 16059 Bursa-Turkey
Photochemical processes have been increasing importance for treatment of textile waste water (1). UV photochemical products of acid blue 113, acid red 57 and reactive blue 160 was investigated using derivative spectrum and multivariate calibration methods. UV spectra of these two dyes have overlapped peaks and it is more likely to be resolved in corresponding derivative spectrum, and so derivatives are an alternative for resolution enhancement. Multivariate calibration methods give better predictions for two closely eluting peaks. Multiple Linear Regression (MLR) and Partial Least Squares (PLS) methods were compared for prediction of compounds in the mixture Degradation period changes with catalyst TiO2 and pH (2). The textile dyes degrades in a short time with TiO2 depending on the type of dye. pH 4, 6 and 8 were studied to follow the degradation period of acid blue 113 and acid red 57. The period is almost the same but initial absorbance is the highest at pH 8 for acid blue 113 and the lowest at pH 4. For acid red 57, the initial absorbance is the highest at pH 6 and the lowest at pH 8. In this study, we followed the degradation time used first and second derivatives for the resolution of two closely eluting peaks. Multivariate calibration was performed on designed experiments.
[1]. Cooper,P., Journal of Society Dyes and Colorist , 109 (1993) 99-100. [2]. Galindo ,C. Kalt,A., Dyes and Pigments 42 (1999) 199-207
79
J. Ins. Sci. Techn. Balıkesir University, 2000, 2 (2), 2nd AACD Special Issue INVESTIGATION OF INTERFERENCES CAUSED BY TEXTILE WASTE WATER MATRICES FOR DETERMINATION OF TRACE
METALS BY ATOMIC ABSORPTION SPECTROMETRY
Belgin İZGİ, Şeref GÜÇER
Uludag University, Science and Art Faculty, Department of Chemistry
16059 Bursa/TURKEY
Determination of metal levels in waste water is important because its toxic role in the biologic treatment processes. The origin of toxic metals in waste water is commonly originated from textile dyes. It was reported that in using acidic dyes chromium amount was increased in waste water and similarly copper from direct dyes (1-3). When non-metallic dyes used total metal concentration is found below the 100-mg/L. It was also reported that some toxic effects are investigated from other chemicals such as detergents during dyeing process (1). Adsorption, ion exchange, coagulation, precipitation, extraction processes were used for removing the organic matrix from waste water (3-5). Spectral interference from organic compounds is affected on the atomic signal and caused poor accuracy of the results Wet and dry ashing methods is recommended for the elimination of organic compounds. Although dry ashing has advantages, but its limited for non-volatile elements. But on the other hand wet ashing is limited because its blank problems.
In our work, UV photo-oxidation method was proposed for the wet ashing of textile waste water. Cd, Pb , Hg, Cu, Zn and Cr analysis by Flame and graphite furnace methods are outlined with the choice of different calibration methods.
References
[1].Shaw T.,Agricultural Chemicals In Raw Wool And The Wool Textile Industry. Symposium Wool Textile Industry Trade Effluents, Inst.Of Water And Envir.Manag.,Rochdale,UK,1994.
[2].ADMI,Dyes and The Environment: Reports on Selected Dyes and Their
Effects: 1. American Dye Manufacturers Institue,USA, 1973.
[3].Yeh R., Thomas A., Journal of Chemical Technology and
80
Technology,58 (1966)217-227.[5]. Tan B.H., Teng T.T.,Omar A.K.M, Water Research, 34 (2000) 597-601.
81
SIMULTANEOUS DERIVATIVE SPECTROPHOTOMETRIC DETERMINATION OF LEAD(II) AND MERCURY(II) BY
2-(5-BROMO-2-PYRIDYLAZO)-5-DIETHYLAMINOPHENOL
Kevser Sözgen and Esma Tütem
Istanbul University, Faculty of Engineering, Department of Chemistry, 34850 Avcılar, Istanbul-TURKEY
The simultaneous analysis of enviromentally important and toxic heavy metal ions such as Pb(II) and Hg(II) that may exist together in contaminated water was aimed. 2-(5-Bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) was chosen as ligand and the conditions for the complex formation of this ligand with Pb(II) and Hg(II) were investigated. The optimal pH range for complex formation was pH 6.0-7.5, and above pH 7.0 for Pb(II) and Hg(II), respectively, and the suitable buffer was pH 7.0 tris buffer. Both complexes were formed immediately and stable for at least 24 hours.
The ordinary, first- and second-derivative spectra of 5-Br-PADAP complexes of Pb(II) and Hg(II) were recorded for both single elements and their binary mixtures. Ordinary spectra of both complexes overlapped. Second-derivative spectra were selected for evaluation, because working wavelength determination was more precise and spectral overlap was less than in first-derivative spectra . Two wavelengths at which 2D-absorbance of one metal had a substantial value as opposed to the zero value of the other (i.e., cross-over points) were 575 nm for Pb(II), and 595 nm for Hg(II). The calibration curves drawn with zero-to-peak values as a function of concentration were linear for these wavelengths. Thus 2D values at 575 and 596 nm of the mixtures were used to determine Pb(II) and Hg(II) concentrations. The relative standard deviation for the analysis of Pb(II) (1.78 mg L-1) individually was 0.45%, and for its admixture with Hg(II)(5.73 mg L-1) was 1.82% . The relative standart deviation for the analysis of Hg(II)(3.44 mg L-1) individually and for its admixture with Pb(II)(2.96 mg L-1) were 0.77% and 1.02%, respectively. The linear range in 2D evaluation was between 7.0x10-7-2x10-5 M for Pb(II) and 5.7x10-6-4.0x10-5 M for Hg(II).
Possible interferences on individual metal (Pb(II) or Hg(II)) analysis by the proposed derivative spectrophotometric method are currently under investigation.
82
83
VOLTAMETRIC INVESTIGATION OF MODIFIED CARBON PASTE ELECTRODE WITH METHYLENE BLUE ON
MUSCOVİTE
Duygu OĞUZ, Yusuf DİLGİN, Zekerya DURSUN, Gürel NİŞLİ
Ege Üniversitesi, Fen Fakültesi, Kimya Bölümü 35100 Bornova – İZMİR
The adsorption of methylene blue was investigated for two species of mica. Muscovite was better to study for the adsorption of methlene blue than chlorite.
The adsorption of methylene blue on muscovite was studied in various conditions and according to muscovite size. Muscovite with methylene blue was used as modifying agent for carbon paste electrode.
Carbon paste electrode either modified with only muscovite or muscovite - methylene blue were studied with using voltammetry in phosphate buffer for two pH.
The effect of He – Ne Laser or Tungsten Lamb light on the modified elektrodes were investigated in the presence of ascorbic asid. The peak current corresponded the oxidation of leuco methlene blue was increased by increasing of ascorbic acid concentration.
84
IMPREGNATED RESINS
M.Arda*, N.Kabay**, Ü.Yüksel*, M.Yüksel**
*Dep.of Chemistry,Ege University,Izmir-Turkey
E-mail:Kesgin@fenfak.ege.edu.tr
**Dep.of Chemical Engineering,Ege University,Izmır-Turkey
Using solvent impregnated resins is an alternative approach to the usual separation techniques for the removal of metal ions. The phenomenon of solvent impregnated resins has been scientifically recognized in 1974 by Warshawsky and Grinstead [1,2]. The concept of SIR is based on the impregnation of a solvent extraction reagent into a porous polymer by a physical impregnation technique. A number of SIR has been prepared by using various polymers supports and organic extractants. Extensive investigations have been carried out with SIR for hydrometallurgical and analytical applications [3]. In this study, Cyanex 302 bis[2,4,4-trimethylpentyl] monothiophosphinic acid has been used as an extractant for the preparation of solvent impregnated resins (SIR). The impregnation was performed by employing macroporous Diaion HP-10 based on poly(styrene-co-diviniylbenzene) and HP-1MG having methacrylic groups as polymer matrices. The optimum impregnation condition for both polymer adsorbents HP-10 and HP-1MG with Cyanex 302 was found as 2 g Cyanex 302/g polymer adsorbent. Metal ion selectivity of solvent impregnated resins was studied by measuring pH dependency of distribution ratios of various metal ions (Cu(II), Cd(II), Zn(II), Pb(II), Co(II), Ni(II), Fe(III), Cr(III), Al(III)) between SIR and nitric acid solutions containing 10-4 M metal ions. Metal analyses were carried out by atomic absorption spectrophotometer. SIR exhibited a higher affinitiy for divalent ions than trivalent ones. The distribution of each metal ions increases in the order Cu>Cd=Pb>Zn>Co at pH 0.5-3 for 1MG based SIR and Cu>Cd>Pb>Zn=Co at pH 1-3 for HP-10 based resins.
85
ION EXCHANGE SEPARATION OF BROMIDE ION BY AN INORGANIC ION EXCHANGER BiO(NO3).0.5H2O
Nalan KABAY1 and Hiroshi KODAMA2
1 Ege University, Department of Chemical Engineering, 35100 İzmir, TURKEY
2 National Institute for Research in Inorganic Metarials, Tsukuba, JAPAN
Disinfection of drinking water is performed either by chlorination or ozonation method. During the chlorination, so-called disifection by-products (DBPs) are produced in the presence of organic matters in water. These are chloroform, bromodichloromethane, chlorodibromomethane and bromoform. These are known as carcinogen trihalomethanes and especially brominated species are more toxic. Ozonation minimizes the production of DBPs associated with chlorination. But, major problem of ozonation is the production of BrO3-, which is a potential carcinogen, obtained by oxidation of bromide. Therefore, there is an increasing concern about the level of bromide in the environment. This has prompted water authorities to find a suitable treatment technique to remove bromide ions.
Kodama reported that BiO(NO3).0.5H2O is a useful compound for removing and solidifying radioactive iodide and chloride ions (1). We have recently studied the ion exchange behavior of BiO(NO3).0.5H2O with regard to fluoride ions (2, 3). We observed that BiO(NO3).0.5H2O is capable removing 99% of the fluoride ions from the solution at pH 1-12. The removal of bromide ions from aqueous solutions at various pH using BiO(NO3).0.5H2O is the subject of this work.
BiO(NO3).0.5H2O was perpared by a solid state reaction between
Bi2O3 and Bi(NO3)3.5H2O. Batch ion exchange reaction tests were carried
our by agitating 200 mg of BiO(NO3).0.5H2O and 4 mL of 0,2 M NaBr
solution at 250C for different periods. The concentration of fluoride ion in the solution was determined by using Dionex 4500i model IC. Kinetic studies for bromide uptake were performed at pH 1, 6.7 and 13. We
observed that BiO(NO3).0.5H2O removed 99% of bromide ions from the
solution at pH 1-13 under the optimal conditions.
The ion exchange reaction of BiO(NO3).0.5H2O with bromide ions was studied under the co-existence of both Cl- and F- at pH 1, 6.6, 12 and 13. The order of decreasing affinity was fonud to be (Br-, Cl-) >F-.
86
1998, pp. 191-198.
[2] N. Kabay, H. Kodama, Solv.Extr.Ion Exch., 18(3), pp.583-603 (2000). [3] N. Kabay, H. Kodama, Proceed. Of the 3rd Med. Basin Conf. on Anal.
Chem. (MBCAC III), Antalya, Turkey, 2000, pp.47.
87
APPLICATION OF PORPHYRIN MODIFIED SORBENTS FOR METALS PRECONCENTRATION
Krzysztof Kilian, Krystyna Pyrzyńska
Department of Chemistry, Warsaw University, Poland.
Development of the new ion-exchange resins for metal preconcentration is still interesting research purpose. Preferred are sorbents with specific functional groups for their higher selectivity.
Porphyris, naturally occurred macrocyclic compounds, are widely used in many analytical techniques as complexing agents and dyes. So far applications are mostly connected with UV-VIS spectrometry and electrochemical methods.
In this study porphyrins were used for modification of commercially available sorbents, to obtain higher selectivity and better kinetics of ion-exchange reaction. Tetra-(4-carboxyphenylo)porphyrin was examined as modifier of anionic resins Amberlite IRA-401 and Amberlite IRA-904 as well as for non-ionic sorbent Amberlite XAD-2. The following parameters were determined: sorption capacity, retention of metals in the function of pH or time and stability of modification versus elution strength. For comparison of results two experiments were done: the sorption of metals on solid phase modified with TCPP and sorption of previously prepared Me-TCPP complexes on raw sorbent.
It was found that effectiveness of sorption the following metals : Mg(II), Co(II), Ni(II), Pb(II), Cd(II), and Cu(II) depends on pH and time of contact with solid phase.
88
SOLID PHASE EXTRACTRACTION OF CHROMIUM SPECIES
Şafak Uluçınar, A. Nur Onar
Ondokuz Mayıs University, Art and Science Faculty, Chemistry Department, Kurupelit 55139 Samsun, Turkey
Chromium can occur in a number of oxidation states, but the trivalent and hexavalent states are usually found in environmental systems. It is well known that each of these oxidation states differ significantly in biological, geochemical and toxicological properties. So, chromium speciation attracts attention. In determination low quantities of Cr species, separation and often pre-concentration procedures are required(1). Most of the papers dealt with the pre-concentration of Cr(VI), because it is much more difficult to find suitable chemical methods and appropriate separation columns for the pre-concentration of Cr(III), owing to the highly inert aqueous complex of Cr(III)(2). Besides, organic ligation of Cr(III) to soluble organic material is critical in the speciation and the solubility of chromium(3).
The aim of this study work is to find adsorbent material that can specifically adsorb not only Cr(III) but also the soluble complexes of chromium(III). For this purpose various adsorbent were tried such as active carbon, alumina, kaolin and pumice. Cr(VI) is adsorbed by alumina and kaolin where as Cr(III) adsorbed onto alumina, active carbon and pumice. In order to separate and pre-concentrate soluble organic chromium(III) complexes pumice surface is modified by hexadecyltrimethyl ammonium, a cationic surface active reagent.
References
[1]
M.J. Marqués, , A. Salvador, A.E. Morales-Rubio, , M. De la Guardia, Analytical methodologies for chromium speciation in solid matrices: a survey of literature, Fresenius J. Anal. Chem. (1988) 362, 239-248.[2]
A. Gaspar, J. Posta and R. Tóth, On-line chromatographic separation and determination of chromium(III) and chromium(VI) with preconcentration of the chromium(III) using potassium hydrogen phthalate, in various samples by flame atomic absorption spectrometry, JAAS (1996) 11,1067-1074.89
[3]
A. R. Walsh and J. O’Halloran, chromium speciation in tannery effluent-I. An assseeement of techniques and the role of organic Cr(III) complexes, Wat. Res. (1996) 10,2393-2400.90
ION EXCHANGE KINETICS OF CHROMIUM ON WEAK CARBOCXYLIC CATIONIC EXCHANGE RESIN
Sevgi Kocaoba, Göksel Akçin
Yıldız Technical University. Faculty of Art and Science. Department of Chemistry. 80270-Sisli-Istanbul-Turkey.
e.mail: kocaoba@yildiz.edu.tr, akcin@yildiz.edu.tr
Chromium is a common pollutant introduced into natural waters textile, leather, tanning, electroplating and metal finishing industries. Weak carboxylic cation exchange resin (Amberlite IRC 76) appears to be very promising for removal and recovery of chromium. The effect of concentration, resin amount, particle size and stirring speed were examined on ion exchange kinetics of chromium with this resin.
The concentration range studied was between 5 to 160 mg/L, the resin amount range was between 5 to 20 mg, the particle size range was between 0.35 to 1.8 mm and stirring speed range was between 1000 to 3500 rpm. Kinetic studies were done with Kressman-Kitchener stirrer reactor system and the results were compared with existing kinetic models.
The kinetic performances of this exchanger were found faster than strong cation exchange resins.
91
VOLTAMMETRIC DETERMINATION OF COPPER ,LEAD AND CADMIUM IN TURNIP JUICE
Nuri Nakiboğlu1 and İbrahim Şahin2
1Balıkesir University,Science and Art Faculty, Chemistry Department, Balıkesir
2Balıkesir University,Necatibey Education Faculty, Chemistry Education Division, Balıkesir
Turnip juice is red, turbid and sour soft drink which is especially produced in South Anatolia Region and is consumed in large quantities It’s ingredients are black carrot,red turnip, table salt, yeast and water. Some manufacturers can additionally use pounded wheat. Alternatively, hot chili pepper can be added in order to produce hot turnip juice. The determination of copper, lead and cadmium,which are typically contaminants in this matrix containing organic substances and inorganic ions, are important.
In this investigation, copper, lead and cadmium contents of the different make turnip juice marketed in Turkey were determined at a hanging mercury drop electrode (HMDE) by square wave anodic stripping voltammetry (SWASV). It is noticed that lead and copper can be directly determined in turnip juice matrix. But cadmium can not be determined directly because of organic matrix interference. Measurements were carried out on both digested and non-digested samples. The same samples were analyzed by ICP-AES method and the results were compared.
Keywords:Turnip juice,anodic stripping voltammetry, heavy metals
92
MAGNESIUM SPECIATION STUDIES OF OLIVE – WATER EXTRACTS
Sema BAĞDAT YAŞAR1, Şeref GÜÇER2
1 Balıkesir University, Science and Arts Faculty, Chemistry Department, 10100 BALIKESİR
2 Uludag University, Science and Arts Faculty, Chemistry Department, 16059 Görükle - BURSA
Magnesium is essential element for living systems. Studies related with Magnesium speciation are gaining importance because of its bioavailability. Recommended daily intake of Magnesium is reported as 400 mg per day ( 1 ). Foodstuff content and chemical forms of Magnesium is an important topic for many researchers. The aim of our work is to study with speciation of Magnesium in olive-water extracts. The total Magnesium content was determined by Flame Atomic Absorption Spectrometry. The elimination of matrix interferences was studied by different matrix modifiers such as Strontium salts. Mg(II) forms were determined using ion selective electrode and compared with ion exchange resin with AAS determinations. For total Magnesium determinations, samples were treated with different acids combinations for wet ashing digestion step. Chloroform extracts were used for organic bounded fractions. The influence of pH was also studied for speciation studies.
References :
[1] Seeling, M.S., Overview: Recognizing the Problem of Magnesium Deficiency, Trace Substance in Environmental Health. XXII [2] Chuang, F.S., Patel, B.M., Reeves, R:D., Glenn, M.T., Winefordner, J.D.,
Determination of Magnesium in Blood Serum and Oil Samples by Atomic Absorption Spectrometry with the Graphite Filament Atomizer, Can. J. Spec., 18, 1(1973), 6-9.
[3] Halls, D.J., Townshend, A., A Study of Some Interferences in the Atomic Absorption Spectrophotometry of Magnesium, Anal. Chim. Acta, 36(1966), 278-285.
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DETERMINATION OF TRACE ELEMENTS IN MARBLE BY FLAME ATOMIC ABSORPTION SPECTROMETRY
Nurhayat ÖZDEMİR1, Şeref GÜCER2
1İnönü University, Faculy of Science, Department of Chemistry 44600 MALATYA,TURKEY
2Uludağ University, Faculy of Science, Department of Chemistry BURSA, TURKEY
The trace content of marble is of increasing importance for distinguishing their origin in archeology and geology. Atomic absorption spectrometry is one of the powerful techniques that widely used trace analysis. Althought there are numerous applications of AAS for geological samples, only a few works were done in marble samples1.
In the present study, atomic absorption spectrometry was utilized using an ammonium pryrrolidine dithiocarbamate /activated carbon preconcentration step to analyse trace levels of Al, Fe, Mn, Ni, Cu, Zn, Co and Cd elements from colored marbles brought from different parts of Turkey.
The interferences from calcium for the mentioned elements are investigated and depressive effect was observed in Mn and Zn determinations. Calcium in the samples was seperated by activated carbon with an efficiency of 99.9%.
The concentrations of varius elements for several samples were found between 49 – 1300 µg/g for Al ; 7 – 990 µg/g for Fe ; 7 – 270 µg/g for Mn ; 0.6 – 134 µg/g for Ni ; 0.4 – 32 µg/g for Cu ; 1.6 – 22 µg/g for Zn ; 0.3 – 2.9 µg/g for Co ; 60 – 380 ng/g for Cd.
Reference
[1]. L. Moens, P. Roos, J.de Rudder, J. Hoste, P.De Paepe, J. Van Hende, R. Marechal, M. Waelkens, J. Radional.Nucl.Chem.,123,333 (1988)
