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Full-Text Articles in Chemistry
The Removal Of Chromium (Vi) From Tannery Waste Using Spirulina Sp. Immobilized Silica Gel, Nais Pinta Adetya, Uma Fadzilia Arifin, Emiliana Anggriyani
The Removal Of Chromium (Vi) From Tannery Waste Using Spirulina Sp. Immobilized Silica Gel, Nais Pinta Adetya, Uma Fadzilia Arifin, Emiliana Anggriyani
Turkish Journal of Chemistry
The use of microalgae biomass is an alternative solution to the problem of environmental pollution due to heavy metals, one of which is Cr metal in leather tanning liquid waste. However, the ability of biomass to adsorb heavy metals has limitations. Therefore, the algal biomass is immobilized with silica gel in order to obtain a stable structure. This research aims to study the absorption efficiency of Cr (VI) metal by the biomass of Spirulina sp. which is immobilized with silica gel from the tannery liquid waste. The preparation stages in this study were adsorbent preparation, immobilization of biomass with silica …
A Review: A Comparison Of Different Adsorbents For Removal Of Cr (Vi), Cd (Ii) And Ni (Ii), Anja Pfeifer, Mojca Skerget
A Review: A Comparison Of Different Adsorbents For Removal Of Cr (Vi), Cd (Ii) And Ni (Ii), Anja Pfeifer, Mojca Skerget
Turkish Journal of Chemistry
A review of the studies dealing with the removal of chromium, cadmium, and nickel ions with different adsorbents published in the literature between 2014 and 2018 is given in tabular form, along with the adsorption conditions, adsorption isotherm, and kinetic models applied by the authors to model the experimental data and adsorption capacities. The review focuses on the efficiency of ion removal.
Chromium Redox Speciation In Food Samples, Krystyna Pyrzynska
Chromium Redox Speciation In Food Samples, Krystyna Pyrzynska
Turkish Journal of Chemistry
Chromium is an element with important biological characteristics, depending on its different species. Cr(III) is considered as essential; however, the Cr(VI) form is classified as carcinogenic.~For this reason, speciation analysis in food samples is a very important question. The proposed data procedures for chromium redox speciation in the literature can be divided into those with the use of online hyphenated techniques and those where appropriate sample pretreatment is necessary. The strategies for nonchromatographic speciation are mainly based on selective liquid--liquid extraction procedures, coprecipitation, selective separation of chromium species using a solid phase extraction column, or complexation reactions. In this paper, …
A Novel Ion-Imprinted Polymeric Sorbent For Separation And Determination Of Chromium(Iii) Species In Wastewater, Barbara Lesniewska, Iwona Jakubowska, Elzbieta Zambrzycka, Beata Godlewska - Zylkiewicz
A Novel Ion-Imprinted Polymeric Sorbent For Separation And Determination Of Chromium(Iii) Species In Wastewater, Barbara Lesniewska, Iwona Jakubowska, Elzbieta Zambrzycka, Beata Godlewska - Zylkiewicz
Turkish Journal of Chemistry
A new chromium(III) ion-imprinted polymer (IIP) was prepared from a Cr(III)-nicotinate complex (template), acrylamide (functional monomer), and ethylene glycol dimethacrylate (cross-linking agent) using 2,2'-azobisisobutyronitrile as the radical initiator. IIP was characterised and used as a selective sorbent for the solid-phase extraction of Cr(III) ions. The conditions for dynamic separation of Cr(III) on IIP were optimised. Cr(III) ions are selectively retained on the sorbent in a pH range from 9 to 10 and can be eluted with 4 mol L$^{-1}$ acetic acid. Cr(III) ions were determined by flame atomic absorption spectrometry (FAAS) with a detection limit of 0.08 $\mu $g mL$^{-1}$. …
Analytical Capabilities Of Two-Phase Hollow-Fiber Liquid Phase Microextraction For Trace Multielement Determination In Aqueous Samples By Means Of Portable Total Reflection X-Ray Instrumentation, Eva Margui, Manuela Hidalgo
Analytical Capabilities Of Two-Phase Hollow-Fiber Liquid Phase Microextraction For Trace Multielement Determination In Aqueous Samples By Means Of Portable Total Reflection X-Ray Instrumentation, Eva Margui, Manuela Hidalgo
Turkish Journal of Chemistry
Liquid phase microextraction (LPME) procedures have been widely used in combination with atomic and emission spectroscopic techniques for the isolation and preconcentration of trace elements. However, its application in combination with total reflection X-ray spectrometry (TXRF) is still scarce. In this paper, we evaluate the possibilities and drawbacks of a two-phase hollow fiber LPME procedure in combination with TXRF for the simultaneous determination of trace amounts of Cr, Ni, Cu, Zn, Pb, and Cd in aqueous samples. After extraction of the analytes by using the optimum conditions (sample volume: 25 mL, complexing agent: APDC, organic solvent: hexylbenzene, extraction time: 2 …
Speciation Of Chromium By The Combination Of Dispersive Liquid--Liquid Microextraction And Microsample Injection Flame Atomic Absorption Spectrometry, Yunusemre Ünsal, Mustafa Tüzen, Mustafa Soylak
Speciation Of Chromium By The Combination Of Dispersive Liquid--Liquid Microextraction And Microsample Injection Flame Atomic Absorption Spectrometry, Yunusemre Ünsal, Mustafa Tüzen, Mustafa Soylak
Turkish Journal of Chemistry
A microextraction procedure was established for the speciation of total Cr, Cr(III), and Cr(VI). Sudan blue II was used as a ligand for speciation works. Some factors affecting the recoveries of chromium species, including type of extraction and dispersive solvents, pH, ligand amount, extraction time, and matrix ions, were examined. Optimum values for the dispersive liquid--liquid microextraction method were pH 6, LOD 0.34 \mu g L^{-1}, and preconcentration factor 400. Chromium(III) was quantitatively recovered under optimal conditions, while the recovery of chromium(VI) was below 10%. The relative standard deviation for Cr(III) determinations for the 10-replicate measurement of 0.3 \mu g …
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.
Synthesis Of Isomorphous Prototypic [Crfe_2o(Aco)_6(Tep)_3]Cl And [Crfe_2o(Aco)_6(Tmp)_3]Cl As Oxo-Centered Hetero Tri-Nuclear Carboxylate Complexes, Massoud Rafizadeh, Reza Tayebee, Vahid Amani
Synthesis Of Isomorphous Prototypic [Crfe_2o(Aco)_6(Tep)_3]Cl And [Crfe_2o(Aco)_6(Tmp)_3]Cl As Oxo-Centered Hetero Tri-Nuclear Carboxylate Complexes, Massoud Rafizadeh, Reza Tayebee, Vahid Amani
Turkish Journal of Chemistry
[CrFe_2O(AcO)_6(TEP)_3]Cl, (1), and [CrFe_2O(AcO)_6(TMP)_3]Cl, (2), were prepared by replacing 3 water molecules in the [CrFe_2O(AcO)_6(H_2O)_3]Cl complex with triethyl- and trimethyl-phosphates, respectively. FT-IR spectroscopy confirmed an oxo-centered, carboxylate-bridged, heteronuclear triangular structure for the title compounds. M_3O and MO_4 units adopted D_{3h} and D_{4h} local symmetry, respectively, and are surrounded by 6 bridging acetates with C_{2v} local symmetry.
Catalytic Spectrophotometric Determination Of Chromium, Angelina Miltcheva Stoyanova
Catalytic Spectrophotometric Determination Of Chromium, Angelina Miltcheva Stoyanova
Turkish Journal of Chemistry
The catalytic effect of chromium(III) and chromium(VI) on the oxidation of sulfanilic acid by hydrogen peroxide was studied. The reaction was followed spectrophotometrically by measuring the absorbance of the reaction product at 360 nm. Under the optimum conditions 2 calibration graphs (for chromium(III) up to 100 ng mL^{-1}, and for chromium(VI) up to 200 ng mL^{-1}) were obtained, using the ``fixed time'' method with detection limits of 4.9 ng mL^{-1} and 3.8 ng mL^{-1}, respectively. The results suggest that at the reaction conditions chromium(VI) is reduced and chromium(III) is oxidized to an intermediate oxidation state and the catalytic action of …
Potentiometric And Spectroscopic Studies With Chromium(Iii) Complexes Of Hydroxysalicylic Acid Derivatives In Aqueous Solution, M. Suat Aksoy, Ulvi̇ye Özer
Potentiometric And Spectroscopic Studies With Chromium(Iii) Complexes Of Hydroxysalicylic Acid Derivatives In Aqueous Solution, M. Suat Aksoy, Ulvi̇ye Özer
Turkish Journal of Chemistry
The stoichiometries and stability constants of the chromium(III) complexes of hydroxysalicylic acid ligands (2,x-dihydroxy benzoic acids; 2,x-DHBA, x = 4-6)(H_3L) were determined in aqueous solution by potentiometry and spectroscopy at 25 °C and at an ionic strength of 0.1 mol L^- (KNO_3). The existence of Cr(HL)^+ type complex was verified. The stability constants of coordination species that exist in Cr(III):2,x-DHBA systems were defined. In the acidic medium the major coordination species involve salicylate type coordination. The formation of monohydroxo complexes was observed at higher pH values.
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 …
^{13}C-And ^{31}P-Nmr Study Of Tetracarbonylbis(Diphenylphosphino)Alkanemetal(0) Complexes Of The Group 6 Elements, Zahi̇de Özer, Sai̇m Özkar
^{13}C-And ^{31}P-Nmr Study Of Tetracarbonylbis(Diphenylphosphino)Alkanemetal(0) Complexes Of The Group 6 Elements, Zahi̇de Özer, Sai̇m Özkar
Turkish Journal of Chemistry
Tetracarbonylbis(diphenylphosphino)alkanemetal(0) complexes of the general formula M(CO)_4[(C_6H_5)_2P (CH_2)_nP(C_6H_5)_2] (M: Cr, Mo, W; n: 1, 2, 3) were synthesized from the reaction of M(CO)_4(\eta^{2:2}-1,5-cyclooctadiene) with the appropriate ligand and characterized by means of IR and NMR (^{13}C and ^{31}P) spectroscopy. Spectroscopic data shows that two phosphorus atoms in the complexes are identical and occupy two cis-coordiantion sites in a pseudo-octahedral coordination sphere of the metal. The comparative study of the coordination shift and the ^{31}P-^{13}C coupling constant reveals that two carbonyl groups trans to one of two phosphorus atoms in the diphosphine ligand are shifted toward the lower magnetic field more …