Recep Ziyadanoğulları

THE SYNTHESIS AND SPECTRAL CHARACTERIZATION OF NEW Cu(II), Ni(II), Co(III), AND Zn(II) COMPLEXES WITH SCHIFF BASE

ABSTRACT Cu(II), Ni(II), Co(III) and Zn(II) complexes with Schiff base have been prepared. Ligand is derived from condensation of 1,2-bis(p>-aminophenoxy)ethane and 2- hydroxynaphthalin-1-carbaldehyde. The complexes have been characterized by elemental analyses, ΛM, IR, UV-VIS, 1H NMR, 13C NMR and magnetic measurements. The ligand is coordinated to the central metal as a tetradentade ONNO ligand. The four bonding sites are the azomethine nitrogen and aldehydic -OH groups.

Synthesis of a mixed-model stationary phase derived from glutamine for HPLC separation of structurally different biologically active compounds: HILIC and reversed-phase applications.

A novel mixed-mode stationary phase was synthesised starting from N-Boc-glutamine, aniline and spherical silica gel (4 µm, 60 Å). The prepared stationary phase was characterized by IR and elemental analysis. The new stationary phase bears an embedded amide group into phenyl ring, highly polar a terminal amide group and non-polar groups (phenyl and alkyl groups). At first, this new mixed-mode stationary phase was used for HILIC separation of four nucleotides and five nucleosides. The effects of different separation conditions, such as pH value, mobile phase and temperature, on the separation process were investigated. The optimum separation for nucleotides was achieved using HILIC isocratic elution with aqueous mobile phase and acetonitrile with 20°C column temperature. Under these conditions, the four nucleotides could be separated and detected at 265 nm within 14 min. Five nucleosides were separated under HILIC isocratic elution with aqueous mobile phase containing pH=3.25 phosphate buffer (10mM) and acetonitrile with 20°C column temperature and detected at 265 nm within 14 min. Chromatographic parameters as retention factor, selectivity, theoretical plate number and peak asymmetry factor were calculated for the effect of temperature and water content in mobile phase on the separation process. The new column was also tested for nucleotides and nucleosides mixture and six analytes were separated in 10min. The chromatographic behaviours of these polar analytes on the new mixed-model stationary phase were compared with those of HILIC columns under similar conditions. Further, phytohormones and phenolic compounds were separated in order to see influence of the new stationary phase in reverse phase conditions. Eleven plant phytohormones were separated within 13 min using RP-HPLC gradient elution with aqueous mobile phase containing pH=2.5 phosphate buffer (10mM) and acetonitrile with 20°C column temperature and detected at 230 or 278 nm. The best separation conditions for seven phenolic compounds was also achieved using reversed-phase HPLC gradient elution with aqueous mobile phase containing pH=2.5 phosphate buffer (10mM) and acetonitrile with 20°C column temperature and seven phenolic compounds could be separated and detected at 230 nm within 16 min.

A new method for recovering Fe(II) sulfate, copper, and cobalt from converter slag

Abstract The aim of this study was to recover copper and cobalt from the stock-piled converter slags at the Ergani Mining Co. in Turkey. Copper and cobalt are present in various chemical forms in the slag. For that reason, copper and cobalt were first converted to Cu2S and CoS by passing H2S gas through a slurry of ground slag in H2SO4 solutions. In the second stage, the slurry was filtered and it was determined that 30–40% of the iron and trace amounts of copper and cobalt passed into the solution as Fe2+, Cu2+, and Co2+ ions. The slag residue was then dried at 105°C for 2 h and roasted in a muffle furnace at about 600–700°C for different time periods. In the third stage, the mass obtained at the end of the roasting process was boiled with distilled water and filtered. The final solution was brought to volume and analyzed for copper and cobalt. It was determined that practically all of the Cu and 70.7% of the Co passed into the solution.

Development of a novel amide-silica stationary phase for the reversed-phase HPLC separation of different classes of phytohormones.

A novel amide-bonded silica stationary phase was prepared starting from N-Boc-phenylalanine, cyclohexylamine and spherical silica gel (4 µm, 60 Å). The amide ligand was synthesised with high yield. The resulting amide bonded stationary phase was characterised by SEM, IR and elemental analysis. The resulting selector bearing a polar amide group is used for the reversed-phase chromatography separation of different classes of thirteen phytohormones (plant hormones). The chromatographic behaviours of these analytes on the amide-silica stationary phase were compared with those of RP-C18 column under same conditions. The effects of different separation conditions, such as mobile phase, pH value, flow rate and temperature, on the separation and retention behaviours of the 13 phytohormones in this system were studied. The optimum separation was achieved using reversed-phase HPLC gradient elution with an aqueous mobile phase containing pH=6.85 potassium phosphate buffer (20 mM) and acetonitrile with a 22 °C column temperature. Under these experimental conditions, the 12 phytohormones could be separated and detected at 230 or 270 nm within 26 min.

Recovery of Uranium, Nickel, Molybdenum, and Vanadium from Floated Asphaltite Ash

ABSTRACT In this study, asphaltite ash obtained from asphaltite was sulfurized under an autoclave condition, and then this sample was floated by two different xanthates. The amount of uranium, nickel, molybdenum, and vanadium in the asphaltite ash was concentrated approximately 12 times. Uranium, nickel, molybdenum, and vanadium in the concentrated samples were separated in the following stages: first the concentrate was leached with different concentrations of (NH4)2CO3 to recover uranium and aluminium; in the second stage, the remaining sample was roasted with treated pyrite at 700°C and leached by water to obtain soluble nickel compounds; in the third stage, the remaining sample was leached with 15 M H2SO4 to solublise molybdenum, titanium, and iron compounds. A solid sample containing vanadium compounds was removed from a solution containing molybdenum, titanium, and iron compounds. This solution was extracted with alamine 336 to separate molybdenum from titanium and iron.

Recovery of MnSO4 from Low-Grade Pyrolusite Ores, and of MnSO4 and Silver from Manganese-Silver Ores

Abstract The aim of this study was to economically recover MnSO4 from low-grade manganese ores, abundantly available in the Southeastern Anatolia Region, and MnSO4 and silver from manganese ores containing silver. In the research carried out thus far, an economical method aimed at treating these ores has not been found. In this study, the recovery of MnSO4 from low-grade manganese ores was realized. The MnSO4 recovered was fairly pure. Our method was then applied to manganese-silver ores; fairly good results were obtained. The silver which remained in the residue following production was taken into a solution medium. In the first stage of our research, studies on pyrolusite ores containing 36.98% manganese were conducted. Ninety-one percent of the manganese was taken into solution as MnSO4 by providing proper conditions (the experiment was carried out with a mixture of 1.8175 g sawdust, 9.1 mL of 96% H2SO4, and 15.7750 g pyrolusite). In the second stage, 94.0% of the manganese existing in used silver-pyro...

HPLC Separation of Different Groups of Small Polar Compounds on a Novel Amide‑Embedded Stationary Phase

Retention behaviors of an amide-embedded silica base stationary phase, which was recently developed by our group, were studied by using six different groups of small polar compounds including phenolic compounds, substituted anilines, chlorinated herbicides, Sudan dyes and some nucleotides and nucleosides in HPLC. The chromatographic behaviors of the prepared stationary phase for these analytes were compared with those of a commercially available reversed-phase column ACE C18 under same conditions. Among the six groups of analytes studied, the amide-silica stationary phase showed enhanced selectivity towards phenolic compounds, substituted anilines, Sudan dyes and herbicides under reversed-phase conditions and satisfactory selectivity towards nucleosides and nucleotides which could not be separated with ACE C18 column under HILIC conditions. Experimental data provided some evidence that functional groups on the stationary phases might have certain degrees of influence on selectivity possibly through secondary interactions with the model compounds. The retentions of the moderately polar compounds such as phenolic acids, anilines and herbicides on the stationary phase are higher than highly polar compounds such as nucleotides and nucleosides due to both the hydrophobic and hydrophilic interactions between the stationary phase and analytes. The quantitative determination of Sudan dyes (I, II, III, and IV) in red chilli peppers was performed. Many red chilli peppers were screened and three of them contained Sudans dyes.

Nano-hemoglobin film based sextet state biomemory device by cross-linked photosensitive hapten monomer

In this study, a biomemory device, consisting of hemoglobin (Hb) cross-linked by MACys-Ru(bipyr)2-MACys) photosensitive monomer cross-linkers, which have memory effect through both Ru3+/2+ in hapten monomer and Fe3+/2+ in redox active center of Hb through multi-charge transfer mechanism, has been improved. Cyclic voltammetry (CV) has been used to determine the redox property of the Hb cross-linked MACys-Ru(bipyr)2-MACys) hapten. Three memory functions, writing, reading and erasing of the fabricated biomemory device, have been accomplished by chronoamperometry (CA) and open-circuit potential amperometry (OCPA). The reliability and repeatability of the biodevice consisting of the p(Hb-co-MACys-Ru(bipyr)2-MACys) sextet state bio-memory layer have been analysed. The Hb film based biodevice on gold electrodes has shown ≥ 2 months the retention time and switched until 106 times continuous cycling without degradation in efficiency. Other hand, the topography of p(Hb-co-MACys-Ru(bipyr)2-MACys) layer on the gold surface has investigated by scanning electron microscopy (SEM) and EDX data.

Recovery of Copper and Cobalt from Converter Slag with a New Flotation Method Using H2S

In this study, two different samples were obtained from Küre Copper factory. It was determined that the samples contain: the sample of K.C.F. (Küre Copper Factory), 0.70% Cu and 0.5% Co. This sample was firstly grounded at -100 mesh dimension. Flotation was done according to previously obtained optimum flotation conditions. The flotation yield of Cu and Co in concentrate phase was found to be low by collective flotation. Even when the samples were grounded at -160 mesh, no change was observed in the flotation result. Especially, Co could not float under the flotation conditions of the non-sulfurized samples. There, a new flotation method was applied which was not applied until now. For this aim, the samples were firstly sulphurised under the steam of H2S + H2O. By this method, the amount of Cu and Co in the samples get rich. According to the obtained results, the optimum reactions for flotation and sulphurization were determined. In the first sulphurization conditions for the sample of K.C.F., the yield of flotation for the Co and Co were found to be 98.27% and 68.07%, respectively. The results indicate that Cu can be floated at low yield in the original samples. On the other hand, Co cannot float under these conditions.

Recovery of Copper and Cobalt from Copper Slags as Selective

This study focuses on the recovery of copper and cobalt from copper slags obtained from Kure district of Kastamonu city, which is in the north of Turkey, and removal of Se, Te, Sb and As from mixture of copper slag and copper concentrate has been conducted. Homogeneous mixtures of slag/pyrite/copper concentrate rate were subjected to roasting at high temperatures in a closed medium and then it was processed roasting at air atmosphere at 600 °C. In the leaching experiments, the effects of roasting time, rate of slag/pyrite/copper concentrate and the effect of the added iron powder to leaching on the metals dissolution were investigated. Under optimum conditions, 99.6% of copper and 98.4% of cobalt were extracted in roasting at high temperatures in a closed medium 3:6:6 of slag/pyrite/copper concentrate rate then roasting at 600 °C at 5 hours. Besides, it was determined that all of Se, Te, Sb and As can be removed from the mixture of slag/pyrite/copper concentrate rate.