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Extraction/Transportation Of Co2+ Metal Ions With Bis(2-Ethylhexyl) Phosphate Dissolved In Kerosene Using A Multidropped Liquid Membrane Technique, Volkan Demi̇rel, Ramazan Donat
Extraction/Transportation Of Co2+ Metal Ions With Bis(2-Ethylhexyl) Phosphate Dissolved In Kerosene Using A Multidropped Liquid Membrane Technique, Volkan Demi̇rel, Ramazan Donat
Turkish Journal of Chemistry
The transport properties of Co2+ ions from the aqueous donor phase to aqueous acceptor phase with the recently developed multidroplet liquid membrane (MDLM) extraction system were studied. This system serves as a continuous process for the transportation of ions and requires fewer reagents for starting and conducting the procedure. Moreover, the procedure results in fewer waste chemicals and mixtures in comparison to traditional extraction methods. During extraction, bis(2-ethylhexyl) phosphate (D2EHPA) was used as a carrier material and 5% potassium thiocyanate (KSCN) solution was used to obtain a colored complex for UV-Vis detection. By means of several experiments, the optimum D2EHPA …
Synthesis And Effect Of Substituent Position, Metal Type On The Electrochemical Properties Of (3-Morpholin-4-Ylpropoxy) Groups Substituted Cobalt, Manganese Phthalocyanines, Zekeri̇ya Biyiklioğlu, Hüseyi̇n Baş
Synthesis And Effect Of Substituent Position, Metal Type On The Electrochemical Properties Of (3-Morpholin-4-Ylpropoxy) Groups Substituted Cobalt, Manganese Phthalocyanines, Zekeri̇ya Biyiklioğlu, Hüseyi̇n Baş
Turkish Journal of Chemistry
In this work, 4-(3-morpholin-4-ylpropoxy)phthalonitrile 2, 3-(3-morpholin-4-ylpropoxy)phthalonitrile 3, Co(II)Pc and Mn(III)Pcs containing (3-morpholin-4-ylpropoxy) groups at peripheral and nonperipheral positions were synthesized. Phthalonitrile derivatives (2 and 3), Co(II)Pc and Mn(III)Pcs (2a, 2b, 3a, 3b) were characterized by using FT-IR, NMR (only for 2 and 3), mass and UV-Vis (except 2 and 3) spectral data techniques. Also, electrochemistry of (3-morpholin-4-ylpropoxy) group substituted Co(II)Pc and Mn(III)Pcs were inspected by using cyclic voltammetry. Electrochemical studies show that (3-morpholin-4-ylpropoxy) group substituted Co(II)Pc and Mn(III)Pcs electropolymerized on the Pt working electrode.
Effect Of Fe Substitution On The Partial Oxidation Of Methane To Syngas Over La$_{0.7}$Sr$_{0.3}$Co$_{1-Y}$Fe$_{Y}$O$_{3-\Delta}$ Perovskites, Adilah Aliyatulmuna, Perry Burhan, Bambang Prijamboedi, Hamzah Fansuri, Irmina Kris Murwani
Effect Of Fe Substitution On The Partial Oxidation Of Methane To Syngas Over La$_{0.7}$Sr$_{0.3}$Co$_{1-Y}$Fe$_{Y}$O$_{3-\Delta}$ Perovskites, Adilah Aliyatulmuna, Perry Burhan, Bambang Prijamboedi, Hamzah Fansuri, Irmina Kris Murwani
Turkish Journal of Chemistry
In this research, a series of La$_{0.7}$Sr$_{0.3}$Co$_{1-y}$Fe$_{y}$O$_{3-\delta }$ ($y =$ 0.0--0.4) was successfully synthesized by a solid-state reaction method and syngas production studies were performed using gas chromatography. Thermogravimetric analysis characterized the concentration of Fe$^{3+}$, which gave a low H$_{2}$/CO ratio over La$_{0.7}$Sr$_{0.3}$Co$_{1-y}$Fe$_{y}$O$_{3-\delta }$ without the presence of molecular oxygen. All samples possessed a purely rhombohedral structure. The incorporation of more Fe increased the lattice parameter and changed XRD peaks of the La$_{1-x}$Sr$_{x}$Co$_{0.8}$Fe$_{0.2}$O$_{3}$ from sharp and single to double. Among the catalyst powders tested for syngas production activity, La$_{0.7}$Sr$_{0.3}$Co$_{0.6}$Fe$_{0.4}$O$_{3-\delta }$ ($y =$ 0.4) had the low molar ratio of H$_{2}$/CO …
Thermolytic Synthesis Of Cobalt And Cobalt Sulfide Nanoparticles Using Cobalt(Ii) N$\Wedge $O Schiff Base Complexes As Single Molecular Precursors, Sandile H. Khoza, Siphamandla C. Masikane, Sixberth Mlowe, Itegbeyogene P. Ezekiel, Thomas Moyo, Neerish Revaprasadu
Thermolytic Synthesis Of Cobalt And Cobalt Sulfide Nanoparticles Using Cobalt(Ii) N$\Wedge $O Schiff Base Complexes As Single Molecular Precursors, Sandile H. Khoza, Siphamandla C. Masikane, Sixberth Mlowe, Itegbeyogene P. Ezekiel, Thomas Moyo, Neerish Revaprasadu
Turkish Journal of Chemistry
Two novel N$\wedge $O-type Schiff base ligands and the corresponding Co(II) complexes are reported. Thermogravimetric analysis indicated that the complexes are potential molecular precursors for the fabrication of cobalt and cobalt-containing nanomaterials. The significant difference in the thermal decomposition profiles is recognized as an influence of structural differences on the complexes. Thus, the complexes were thermally decomposed using the melt and hot injection methods to examine the properties of the obtained cobalt and cobalt sulfide nanoparticles, respectively. The reaction parameters employed during the fabrication processes, in addition to structural differences, influenced the morphological and crystallographic phases and magnetic properties of …
Hydrolysis Of Ammonia Borane And Hydrazine Borane By Poly($N$-Vinyl-2-Pyrrolidone)-Stabilized Copd Nanoparticles For Chemical Hydrogen Storage, Murat Rakap, Bayram Abay, Ni̇hat Tunç
Hydrolysis Of Ammonia Borane And Hydrazine Borane By Poly($N$-Vinyl-2-Pyrrolidone)-Stabilized Copd Nanoparticles For Chemical Hydrogen Storage, Murat Rakap, Bayram Abay, Ni̇hat Tunç
Turkish Journal of Chemistry
For the first time the synthesis of poly($N$-vinyl-2-pyrrolidone)-stabilized cobalt-palladium nanoparticles by an easy method, their characterization, and their use as active catalysts for hydrogen release from hydrolysis of ammonia borane and hydrazine borane is reported here. The catalyst is prepared by simultaneous reduction of suitable cobalt and palladium ions by sodium borohydride in the presence of poly($N$-vinyl-2-pyrrolidone) as a stabilizer. They are characterized by UV-Vis spectroscopy, TEM analysis, X-ray diffraction, and X-ray photoelectron spectroscopy. They provide average turnover frequencies of 30 min$^{-1}$ and 45 min$^{-1}$ in the hydrolysis of ammonia borane and hydrazine borane. They also provide activation energies of …
Investigation Of Binary Co$_{2}$X (X = In, Si, Sb, Sn, Ga) Half-Heusler Alloys, Adewumi Isaac Popoola
Investigation Of Binary Co$_{2}$X (X = In, Si, Sb, Sn, Ga) Half-Heusler Alloys, Adewumi Isaac Popoola
Turkish Journal of Physics
The electronic structure and mechanical properties of some cobalt-based binary half-Heusler alloys Co$_{2}$X (X = In, Si, Sb, Sn, Ga) have been investigated using the density functional theory approach. The site preference by cobalt and X is similar to the traditional half-Heusler structure. The results showed that Co$_{2}$Si is not a half-metal but rather an n-type degenerate semiconductor. The compounds Co$_{2}$Ga, Co$_{2}$Sb, and Co$_{2}$Sn are thermodynamically unstable and Co$_{2}$In is elastically unstable. With much care given to the lattice size, half metallicity is readily predicted in Co$_{2}$In, Co$_{2}$Ga, Co$_{2}$Sn, and Co$_{2}$Sb. All the compounds showed directional bonding and they should …
Synthesis And Electrochemistry Of Phthalocyanines Bearing [(3,4-Dimethoxybenzyl)Oxy] Groups, İpek Ömeroğlu, Zekeri̇ya Biyiklioğlu
Synthesis And Electrochemistry Of Phthalocyanines Bearing [(3,4-Dimethoxybenzyl)Oxy] Groups, İpek Ömeroğlu, Zekeri̇ya Biyiklioğlu
Turkish Journal of Chemistry
In this study peripherally tetra-substituted metal-free, metallophthalocyanines bearing (3,4-dimethoxybenzyl) oxy groups have been synthesized and characterized. Electrochemical properties of novel phthalocyanines 4, 5, 6, and 7 were determined by cyclic and square wave voltammetry in order to define their possible applications in different electrochemical technologies. Co^{II} and Ti^{IV}O metal ions behave as redox active cations in the core of the CoPc and TiOPc complexes, respectively. Voltammetric studies revealed that phthalocyanines have reversible/irreversible redox processes, which are the main requirement for the technological usage of these compounds.
Microwave-Assisted Synthesis And Characterization Of Co(Ii) Phthalocyanine And Investigation Of Its Catalytic Activity On 4-Nitrophenol Oxidation, Ece Tuğba Saka, Zekeri̇ya Biyiklioğlu, Hali̇t Kanteki̇n
Microwave-Assisted Synthesis And Characterization Of Co(Ii) Phthalocyanine And Investigation Of Its Catalytic Activity On 4-Nitrophenol Oxidation, Ece Tuğba Saka, Zekeri̇ya Biyiklioğlu, Hali̇t Kanteki̇n
Turkish Journal of Chemistry
In this study, new cobalt phthalocyanine containing a 2-(2-benzothiazolylthio)ethoxy group at peripheral positions has been synthesized and characterized by spectroscopic methods (IR, UV-Vis elemental analysis, and mass spectroscopies). Catalytic activity of Co(II) phthalocyanine has been investigated in the presence of oxidants such as tert-buthylhydroperoxide, m-chloroperoxybenzoic acid, and H_2O_2. Co(II) phthalocyanine shows catalytically activity and product conversion under mild conditions. To find the optimal conditions in the oxidation process, substrate ratio, oxidant ratio, temperature, and oxidant type were examined over 3 h. The results exhibit the best optimum reaction conditions in this catalytic system.
Orthogonal Signal Correction -- Partial Least Squares Method For Simultaneous Spectrophotometric Determination Of Nickel, Cobalt, And Zinc, Ali Niazi, Amir Azizi
Orthogonal Signal Correction -- Partial Least Squares Method For Simultaneous Spectrophotometric Determination Of Nickel, Cobalt, And Zinc, Ali Niazi, Amir Azizi
Turkish Journal of Chemistry
The simultaneous determination of nickel, cobalt, and zinc mixtures by spectrophotometric method is a difficult problem in analytical chemistry, due to spectral interferences. By multivariate calibration methods, such as partial least squares (PLS) regression, it is possible to obtain a model adjusted to the concentration values of the mixtures used in the calibration range. Orthogonal signal correction (OSC) is a preprocessing technique used for removing the information unrelated to the target variables based on constrained principal component analysis. OSC is a suitable preprocessing method for partial least squares calibration of mixtures without loss of prediction capacity using spectrophotometric method. In …
Template Synthesis And Structural Characterization Of Homo Binuclear Chromium(Iii), Manganese(Iii), Iron(Iii), Cobalt(Iii), And Ruthenium(Iii) Complexes With Octaazamacrocyclic Ligands, Vinod K. Sharma, Shipra Srivastava
Template Synthesis And Structural Characterization Of Homo Binuclear Chromium(Iii), Manganese(Iii), Iron(Iii), Cobalt(Iii), And Ruthenium(Iii) Complexes With Octaazamacrocyclic Ligands, Vinod K. Sharma, Shipra Srivastava
Turkish Journal of Chemistry
The Schiff base octaazamacrocyclic ligands derived from primary diamines and 3,6-dimethyl/diphenyl-4,5-diazaocta-3,5-diene-2,7-dione, and their binuclear complexes [M_2LCl_4]Cl_2 [M = Cr(III), Fe(III), Co(III), or Ru(III)] and [Mn_2L(AcO)_4](AcO)_2 were synthesized by template condensation reactions. Attempts to synthesize the corresponding metal-free macrocyclic ligands did not prove successful. The overall geometry and stereochemistry of these complexes were elucidated by elemental analyses, magnetic susceptibilities, electronic spectra, infrared spectra, molar conductance measurements, ^1H NMR, and thermogravimetric analysis. All the trivalent metal ion complexes appear to be 1:2 electrolytes. An octahedral geometry is proposed for all the complexes.
First- And Second-Derivative Spectrophotometry For Simultaneous Determination Of Copper And Cobalt By 1-(2-Pyridylazo)-2-Naphthol In Tween 80 Micellar Solutions, Habibollah Eskandari, Ali Ghanbari Saghseloo, Mansour Arab Chamjangali
First- And Second-Derivative Spectrophotometry For Simultaneous Determination Of Copper And Cobalt By 1-(2-Pyridylazo)-2-Naphthol In Tween 80 Micellar Solutions, Habibollah Eskandari, Ali Ghanbari Saghseloo, Mansour Arab Chamjangali
Turkish Journal of Chemistry
1-(2-Pyridylazo)-2-naphthol (PAN) has been used for the simultaneous determination of copper and cobalt at trace levels. PAN at pH 1.89 forms red and green complexes with copper and cobalt, respectively, which are soluble in aqueous Tween 80 micellar media and are stable for at least 3 days. Under optimum conditions, calibration graphs were obtained for individual determination of copper and cobalt by zero- and first-derivative spectrophotometry and for simultaneous determination by first- and second-derivative spectrophotometry. Zero-crossing first-derivative spectrophotometry at 555 and 581 nm for cobalt and copper was used for the simultaneous determination, respectively. The second derivative method at 577 …
Study On The Solid Phase Extraction And Spectrophotometric Determination Of Cobalt With 2-(2-Quinolylazo)-5-Diethylaminoaniline, Qiufen Hu, Guangyu Yang, Xuechang Dong, Jiayuan Yin
Study On The Solid Phase Extraction And Spectrophotometric Determination Of Cobalt With 2-(2-Quinolylazo)-5-Diethylaminoaniline, Qiufen Hu, Guangyu Yang, Xuechang Dong, Jiayuan Yin
Turkish Journal of Chemistry
A sensitive, selective and rapid method for the determination of cobalt based on the rapid reaction of cobalt(II) with QADEAA and the solid phase extraction of the Co(II)-QADEAA chelate with C_{18} membrane disks was developed. In the presence of pH = 5.5 buffer solution and cetyl trimethylammonium bromide (CTMAB) medium, QADEAA reacts with cobalt to form a violet complex with a molar ratio of 1:2 (cobalt to QADEAA). This chelate was enriched by the solid phase extraction with C_{18} membrane disks. An enrichment factor of 50 was obtained by elution of the chelate from the disks with a minimal amount …
Determination Of Trace Elements In Iron Minerals By Atomic Absorption Spectrometry, Trajce Stafilov, Dragica Zendelovska
Determination Of Trace Elements In Iron Minerals By Atomic Absorption Spectrometry, Trajce Stafilov, Dragica Zendelovska
Turkish Journal of Chemistry
A method for the determination of lead, cobalt, nickel, chromium, zinc and manganese in iron minerals siderite (FeCO_3), hematite (Fe_{2}O_{3), pyrite and marcasite (FeS_{2) by flame and Zeeman electrothermal atomic absorption spectrometry (ETAAS) was developed. Interferences were investigated by measuring the absorbance of the elements investigated in series of samples with varying mass ratios of the elements investigated and iron as the potential interfering element. It was found that there was no interference in the determined mass ratios of iron on the absorbance of Mn and Zn and that they could be directly analyzed by flame and electrothermal atomic absorption …