Ahmet Uyanik

Effect of the Adsorptive Character of Filter Papers on the Concentrations Determined in Studies Involving Heavy Metal Ions

Analytical filter papers are generally made of fibrous cellulose which has the potential to adsorb metal ions. In this study, blue band ashless filter paper was used to demonstrate one of the sources of error in the determination of the concentration of Fe2+, Co2+, Mn2+, Cd2+, Cu2+, Pb2+ and Zn2+ ions. For this purpose, the metal ion content of standard solutions in the 1–100 mg/ℓ concentration range was analysed via FAAS before and after the filtration process. The corresponding results and the calculated percentage errors due to adsorption are presented. The effect of pH on the adsorption process was also investigated. Activated carbon and soil samples were spiked with each metal ion and the solid phases from the resulting solutions were separated by both filter paper methods and centrifugation. In the statistical estimation of the results, the paired t-test was applied for non-filtered and filtered solutions in the concentration range 1–100 mg/ℓ using the data analysis tools available in MS Excel®. The use of filter paper caused systematic errors, particularly at lower metal concentrations, and hence centrifugation or a filtering process using techniques other than filter paper is favoured as a better approach towards estimating the concentration of heavy metal ions from aqueous solution.

Distribution of uranium in the production of triple superphosphate (TSP) fertilizer and phosphoric acid

In this study the distribution of uranium, which is one of the radioactive elements present in phosphate fertilizers was investigated in different steps of the triple superphosphate (TSP) production process. The uranium in phosphate rock, phosphoric acid, phosphogypsum and TSP was extracted into the organic phase by using the TOPO extraction method. The uranium contents of these materials were determined by measuring the absorbance of the formed (pH 7.6) uranyl bromo-PADAP [uranyl(2-(5-bromo-2-pyridylazo)-5-diethylaminophenol)] complex solutions at 574 nm against blank. It was found that 50% of the uranium is dissolved in the acid during the production of phosphoric acid while the remainder is precipitated with phosphogypsum residue. The observations showed that in the second step, the sum of uranium in phosphate rock and phosphoric acid completely passed into TSP in the TSP manufacturing process.

Accumulation of Heavy Metals in Water, Sediments and Wetland Plants of Kizilirmak Delta (Samsun, Turkey)

In this study, concentrations of heavy metals (Fe, Mn, Ni, Co, Zn, Cu, and Pb) were measured in water bodies including streams, bottom sediments and various wetland plants of Kızılırmak Delta. Kızılırmak Delta is one of the largest and the most important natural wetlands in Turkey and has been protected by Ramsar convention since 1993. The heavy metal concentrations in water were found lower than that of national standards for protected lakes and reserves. In bottom sediments and wetland plants, however, the accumulated amounts of different heavy metals varied in the following order: Fe>Mn>Zn>Ni>Co>Cu>Pb, and Fe>Mn>Zn>Ni>Co respectively. Heavy metal uptake of Hydrocharis morsus-ranae and Myriophyllum verticillatum plants among others were found far above the toxic levels and they might be used as bio-indicators and heavy metal accumulators in polluted natural areas.

Effect of EDTA and Tannic Acid on the Removal of Cd, Ni, Pb and Cu from Artificially Contaminated Soil by Althaea rosea Cavan

In this study an ornamental plant of Althaea rosea Cavan was investigated for its potential use in the removal of Cd, Ni, Pb and Cu from an artificially contaminated soil. Effect of two different chelating agents on the removal has also been studied by using EDTA (ethylenediaminetetracetic acid) and TA (tannic acid). Both EDTA and TA have led to higher heavy metal concentration in shoots and leaves compared to control plants. However EDTA is generally known as an effective agent in metal solubilisation of soil, in this study, TA was found more effective to induce metal accumulation in Althaea rosea Cavan under the studied conditions. In addition to this, EDTA is toxic to some species and restraining the growth of the plants. The higher BCF (Bio Concentration Factor) and TF (Translocation Factor) values obtained from stems and leaves by the effects of the chemical enhancers (EDTA and TA) show that Althaea rosea Cavan is a hyper accumulator for the studied metals and may be cultivated to clean the contaminated soils.

Synthesis, thermal, spectroscopic and structural properties of di(aqua)bis(N, N′-dimethylethylenediamine-κ2N, N′)copper(II) acesulfamate

The complex [Cu(C4H12N2)2(H2O)2]2+ [(C4H4NO4S)–]2, which is the first structurally characterized complex with acesulfamate as the counter anion, has been synthesized and characterized by elemental analyses, magnetic and conductivity measurements, UV/vis, FT-IR and mass spectra. The thermal behaviour of the complexes was studied by simultaneous TG, DTG and DTA methods in a static air atmosphere. In the crystal structure, the copper cation, lying on a crystallographic centre of symmetry, adopts an elongated octahedral trans-[CuN4O2] coordination geometry, with long axial Cu–O(aqua) bond length and short equatorial Cu–N bonds, of 2.479(2), 2.035(2) and 2.051(2) Å, respectively. The coordinated water molecules together with the amine part of the dimethylethylene diamine molecule link the acesulfamate ions to the metal complex via intermolecular hydrogen bonds.

EDTA Supported Phytoextraction of Cd from Contaminated Soil by Four Different Ornamental Plant Species

ABSTRACT In this study, some ornamental plant species such as Althaea rosea Cavan, Lonicera japonica Thunb, Salvia virgata Jacq. (Lamiaceae), and Dahlia hybrida growing in the natural vegetation of Black Sea Region (Turkey) were investigated for their phytoextraction potential of cadmium (Cd) from artificially contaminated soil of 10, 25, 50, and 100 mg/kg concentration under pot conditions. Effect of ethylenediaminetetracetic acid (EDTA) on this removal has also been studied. To evaluate the removal efficiency of the studied plants, the bioconcentration factor (BCF) and translocation factor (TF) values were also calculated. Higher BCF and TF values obtained from stems and leaves of A. rosea Cavan, L. japonica Thunb, and S. virgata Jacq. (Lamiaceae) show that those plants might be cultivated and used as hyperaccumulators in the removal of Cd from the contaminated soils. EDTA enhanced the Cd phytoextraction in plants; however, at the same time it resulted in a slight decrease in the dry matter.

Evaluation of trace metals in sediment, water, and fish (Mugil cephalus) of the central Black Sea coast of Turkey

ABSTRACT In this study, concentrations of trace metals such as As, Cd, Cu, Cr, Fe, Pb, Ni, Sn, Se, and Zn were determined in sediments, water, and a kind of fish (Mugil cephalus) of the central Black Sea coasts by employing Inductively Coupled Plasma Mass Spectrometry and microwave digestion technique. Gill, muscle, liver, and other tissues were analyzed separately for each sample. The accuracy of the results were checked by using a certified reference material (DORM-4). In water samples, the metal determined at highest concentrations was Cu (1645.44 µg/L). In sediment samples, the metal determined at highest concentrations was Fe (12223.50 mg/kg). The levels of trace metals found in the different parts of the fish were: Zn in muscle tissue (30393.28 mg/kg), Sn in gill tissue (5140.08 mg/kg), and Cu in liver tissue (289.31 mg/kg). These results were also compared with various relevant guidelines and literature.