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Full-Text Articles in Chemistry
Adsorption Of Copper Ions And Alizarin Red S From Aqueous Solutions Onto A Polymeric Nanocomposite In Single And Binary Systems, Omnia Ali, Sahar Mohamed
Adsorption Of Copper Ions And Alizarin Red S From Aqueous Solutions Onto A Polymeric Nanocomposite In Single And Binary Systems, Omnia Ali, Sahar Mohamed
Turkish Journal of Chemistry
Adsorption of Cu(II) ions and alizarin red S (ARS) has been studied using beads of chitosan (CS) and a chitosan/ZnO nanorod composite (CS-ZnO) in single and binary systems. The beads were synthesized and characterized using Fourier transform infrared spectroscopy, X-ray diffraction, high-resolution transmission electron microscopy, scanning electron microscopy, and energy dispersive X-ray analysis. Factors affecting adsorption of Cu(II) ions and ARS such as pH and initial concentrations as well as adsorption kinetics, isotherms, thermodynamics, reusability, and competitive adsorption in binary systems were studied. The results showed that the adsorption kinetics and isotherm data for both adsorbates followed a pseudo-second-order model …
Preparation, Characterization, And Adsorption Studies Of Core@Shell Sio$_{2}$@Ceo$_{2}$ Nanoparticles: A New Candidate To Remove Hg(Ii) From Aqueous Solutions, Ali̇ İmran Vai̇zoğullar, Ahmet Balci, İbrahi̇m Kula, Mehmet Uğurlu
Preparation, Characterization, And Adsorption Studies Of Core@Shell Sio$_{2}$@Ceo$_{2}$ Nanoparticles: A New Candidate To Remove Hg(Ii) From Aqueous Solutions, Ali̇ İmran Vai̇zoğullar, Ahmet Balci, İbrahi̇m Kula, Mehmet Uğurlu
Turkish Journal of Chemistry
SiO$_{2}$ supported core@shell nanoparticles (CSNs) have recently attracted great attention due to their unique, tunable, optical, photocatalytic, and higher adsorption properties. In this study, SiO$_{2}$@CeO$_{2}$~CSNs were synthesized using a chemical precipitation technique and characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM) analysis. XRD analysis showed that SiO$_{2\, }$particles were the core while CeO$_{2}$ particles were the shell. It was seen as a new band at 961 cm$^{-1}$ of the oxygen bridge between Si and Ce atoms from FT-IR results; SiO$_{2}$ and CSNs were spherical (0.5--0.6 $\mu $m) from SEM and …
Remediation Of Cr(Vi) Via Combined Self-Reduction And Adsorption Bychemically Modified Carbon Sorbents, Mohamed E. Mahmoud, Amr. A. Yakout, Asmaa M. Halbas, Maher M. Osman
Remediation Of Cr(Vi) Via Combined Self-Reduction And Adsorption Bychemically Modified Carbon Sorbents, Mohamed E. Mahmoud, Amr. A. Yakout, Asmaa M. Halbas, Maher M. Osman
Turkish Journal of Chemistry
Hexavalent chromium, Cr(VI), is a highly toxic species, while trivalent chromium, Cr(III), is an essential trace element for humans and other organisms. In the present work, a simple, rapid, and efficient procedure for water treatment of Cr(VI) is described. Active carbon (AC) was chemically treated with HCl and NaOH for the formation of surface modified Acidic-AC and Basic-AC sorbents, respectively. In addition, AC sorbent was treated with HNO$_{3}$ as an oxidizing agent and sodium sulfite as a reducing agent for the formation of Ox-AC and Rd-AC sorbents, respectively. The modified AC sorbents were tested to identify their potential applications in …
Adsorption Of Cellulase On Poly(2-Hydroxyethyl Methacrylate) Cryogels Containing Phenylalanine, Murat Yavuz, Oğuz Çakir, Zübeyde Baysal
Adsorption Of Cellulase On Poly(2-Hydroxyethyl Methacrylate) Cryogels Containing Phenylalanine, Murat Yavuz, Oğuz Çakir, Zübeyde Baysal
Turkish Journal of Chemistry
The aim of this study was to prepare a supermacroporous cryogel that can be used for the adsorption of cellulase. The macroporous cryogel of poly(2-hydroxyethyl methacrylate-N-methacryloyl-l-phenylalanine) [p(HEMA-MAPA)] was prepared by copolymerization of 2-hydroxyethyl methacrylate (HEMA) with a functional monomer of N-methacryloyl-l-phenylalanine (MAPA). The cryogel was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and swelling tests. The effects of several parameters such as medium pH, temperature, ionic strength, and flow rate on cellulase adsorption were also investigated. Maximum cellulase adsorption was observed at 25 $^{\circ}$C and pH 4.0. Furthermore, adsorbed cellulase was desorbed from the cryogel by using 1.0 …
Adsorptive Features Of Polyacrylamide--Aluminosilicate Composites For Methylene Blue, Demet Baybaş, Ulvi̇ Ulusoy
Adsorptive Features Of Polyacrylamide--Aluminosilicate Composites For Methylene Blue, Demet Baybaş, Ulvi̇ Ulusoy
Turkish Journal of Chemistry
Polyacrylamide--montmorillonite (PAAm-Mt) and polyacrylamide--clinoptilolite (PAAm-Z) composites were prepared by cross-linked polymerization of acrylamide in dispersions of Mt and Z. The composites were characterized by FT-IR, SEM, XRD, CEC, and PZC analysis. The adsorptive features of PAAm-Mt and PAAm-Z for methylene blue (MB) were investigated by their relevance to initial dye concentration, temperature, contact time, PZC, and pH. The monolayer adsorption capacities were 0.14 and 0.08 mol kg$^{-1}$ for PAAm-Z and PAAm-Mt, respectively. The changes in pH of MB solution had an insignificant influence on their adsorption capacities. The values of enthalpy and entropy changes were positive ($\Delta $H$_{PAAm-Mt}$ = 7.6 …
Optimization Of The Adsorption Of A Textile Dye Onto Nanoclay Using A Central Composite Design, Aydin Hassani, Murat Kiranşan, Reza Darvishi Cheshmeh Soltani, Alireza Khataee, Semra Karaca
Optimization Of The Adsorption Of A Textile Dye Onto Nanoclay Using A Central Composite Design, Aydin Hassani, Murat Kiranşan, Reza Darvishi Cheshmeh Soltani, Alireza Khataee, Semra Karaca
Turkish Journal of Chemistry
The main aim of this study was to evaluate the efficacy of montmorillonite clay for the adsorption of C.I. Basic Yellow 2 (BY2) dye from aqueous media. The experimental results were processed by response surface methodology based on a central composite design (CCD). The effect of four main variables, including initial BY2 concentration, adsorbent dosage, reaction time, and temperature on the removal of BY2 was evaluated by the model. The accuracy of the model and regression coefficients was appraised by employing analysis of variance. The results demonstrated a good agreement between the predicted values obtained by the model and the …
Separation And Preconcentration Of Lead(Ii), Cobalt(Ii), And Nickel(Ii) On Edta Immobilized Activated Carbon Cloth Prior To Flame Atomic Absorption Spectrometric Determination In Environmental Samples, Zeid Abdullah Alothman, Erkan Yilmaz, Mohamed Habi̇la, Mustafa Soylak
Separation And Preconcentration Of Lead(Ii), Cobalt(Ii), And Nickel(Ii) On Edta Immobilized Activated Carbon Cloth Prior To Flame Atomic Absorption Spectrometric Determination In Environmental Samples, Zeid Abdullah Alothman, Erkan Yilmaz, Mohamed Habi̇la, Mustafa Soylak
Turkish Journal of Chemistry
The synthesis and characterization of ethylenediaminetetraacetic acid immobilized activated carbon cloth was performed in the present work. It was used for preconcentration-separation of lead(II), cobalt(II), and nickel(II) at trace levels as an adsorbent. Factors including pH, concentration and volume of eluent, sample and eluent flow rates, sample volume, and effect of coexisting ions on the solid phase extraction of analytes were examined. The preconcentration factor was 50. The detection limits for Pb(II), Co(II), and Ni(II) were 4.39, 0.99 and 0.91 $\mu $g L$^{-1}$, respectively. The adsorption capacity for Pb(II), Co(II), and Ni(II) ions was found as 11.0, 11.2, and 10.2 …
Influence Of Acid And Heavy Metal Cation Exchange Treatments On Methane Adsorption Properties Of Mordenite, Meryem Sakizci, Leyla Özgül Kilinç
Influence Of Acid And Heavy Metal Cation Exchange Treatments On Methane Adsorption Properties Of Mordenite, Meryem Sakizci, Leyla Özgül Kilinç
Turkish Journal of Chemistry
In this study, the adsorption of methane (CH$_{4})$ capacities onto natural mordenite obtained from \.{I}zmir, Turkey, and its cationic forms (CuM, AgM, FeM, and HM samples) were investigated at the temperatures of 0 and 25 $^{\circ}$C up to 100 kPa. Natural and modified samples were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared (FT-IR), thermogravimetry (TG-DTG), differential thermal analysis (DTA), scanning electron microscopy (SEM) coupled with energy dispersion spectroscopy (EDS), and N$_{2}$ adsorption methods. Quantitative XRD analysis showed that the major component of the natural zeolite was mordenite, together with minor amounts of quartz, feldspar, and clay …
Immobilized Metal Ion Affinity Nanospheres For \Alpha-Amylase Immobilization, Tülden Kalburcu, Müni̇re Nalan Tüzmen, Si̇nan Akgöl, Adi̇l Deni̇zli̇
Immobilized Metal Ion Affinity Nanospheres For \Alpha-Amylase Immobilization, Tülden Kalburcu, Müni̇re Nalan Tüzmen, Si̇nan Akgöl, Adi̇l Deni̇zli̇
Turkish Journal of Chemistry
Immobilized metal chelate affinity chromatography (IMAC) support was practiced for \alpha-amylase immobilization. Poly(hydroxyethylmethacrylate-methacryloylamidotryptophan)-Ni^{2+} [p(HEMA-MAT)-Ni^{2+}] nanospheres, average diameter 100 nm, were produced by surfactant free emulsion polymerization. Characterizations of p(HEMA-MAT)-Ni^{2+} nanospheres were carried out by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM). In addition, average particle size, size distribution, and surface charge were specified. The amount of N-methacryloylamidotryptophan (MAT) incorporated to polymer was determined as 1.95 mmol/g polymers by using nitrogen stoichiometry. The specific surface areas of poly(hydroxyethylmethacrylate) [p(HEMA)] and p(HEMA-MAT) nanospheres were calculated as 1856 m^2/g and 1914 m^2/g, respectively. Protein adsorption increased with increasing initial protein …
Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei
Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei
Turkish Journal of Chemistry
The adsorption of the urea molecule on the external surface of the B_{12}N_{12} nanocage was investigated using density functional theory (DFT) calculations. Adsorption of urea on the nanocage releases energies of about --23.70 to --29.50 kcal/mol with a significant NBO charge transfer from the urea to the nanocage. It was also found that the urea molecule can be strongly chemisorbed on the surface of the nanocage with Gibbs free energies of -7.91 to -14.81 kcal/mol. The HOMO--LUMO gap of the nanocage does not change significantly upon urea adsorption, while the Fermi level is dramatically changed from -4.27 eV in the …
Theory Of Adsorption Equilibria Analysis Based On General Equilibrium Constant Expression, Abdul Sattar Ali Khan
Theory Of Adsorption Equilibria Analysis Based On General Equilibrium Constant Expression, Abdul Sattar Ali Khan
Turkish Journal of Chemistry
Adsorption equilibria were analyzed on the basis of general equilibrium constant expression for the development of fundamental adsorption equations (Freundlich, Langmuir, and BET) in connection with the establishment of a general approach towards physical interpretations of adsorption parameters. Theoretically it was proved that Freundlich plot analysis cannot be used to find useful parameters such as the monolayer adsorption capacity of an adsorbent. The present theory also indicated that the adsorption process with known value of monolayer adsorption capacity can be studied for finding various equilibrium constants on the basis of the Fronaeus equation, which is commonly used in the complexation …
The Role Of The Entropy Factor On The Adsorption Of An Optical Brightener On Pulp, Greta Radeva, Eva Valcheva, Stefka Veleva
The Role Of The Entropy Factor On The Adsorption Of An Optical Brightener On Pulp, Greta Radeva, Eva Valcheva, Stefka Veleva
Turkish Journal of Chemistry
The present paper reports results of the thermodynamic study of adsorption of 2 optical brighteners (Tinopal UP and Leucophor AP) on pulp. The entropy non-homogeneity of the pulp surface was confirmed and the coefficients of entropy non-homogeneity were determined. The entropy effect on the variation of Gibbs free energy of the process studied was followed.
The Effect Of Silane Modification On The Adsorptive Properties Of Natural Pyrophyllite And Synthetic Titanium-Based Powders Prepared By The Sol-Gel Process, Şadi̇ye Şener, Murat Erdemoğlu, Meltem Asi̇ltürk, Hi̇kmet Sayilkan
The Effect Of Silane Modification On The Adsorptive Properties Of Natural Pyrophyllite And Synthetic Titanium-Based Powders Prepared By The Sol-Gel Process, Şadi̇ye Şener, Murat Erdemoğlu, Meltem Asi̇ltürk, Hi̇kmet Sayilkan
Turkish Journal of Chemistry
Our aim was to improve the relatively poor adsorption characteristics of natural pyrophyllite and those of TiO_m and Ti(OR)_x(OH)_y(O)_z obtained from titanium tetraisopropoxide (TTIP) by the sol-gel process. For this purpose, the surfaces of the above-mentioned adsorbents were coated with a surface modifier by dipping them in 1% and 50% (w/w) solutions of N-(2-aminoethyl)-3- aminopropyltrimethoxysilane (DIAMO) in methanol. Realization of the coating processes was checked by FT-IR and SEM analyses. FT-IR analyses of the coated powders heat treated at 110 °C showed that condensation took place between OH groups of prehydrolyzed silane molecules and hydroxyl groups and/or oxygen atoms on …
New Adsorbents From Ti(Opr^{N})_{4} By The Sol-Gel Process: Synthesis, Characterization And Application For Removing Some Heavy Metal Ions From Aqueous Solution, Funda Sayilkan, Hi̇kmet Sayilkan, Sema Erdemoğlu, Şadi̇ye Şener, Murat Akarsu
New Adsorbents From Ti(Opr^{N})_{4} By The Sol-Gel Process: Synthesis, Characterization And Application For Removing Some Heavy Metal Ions From Aqueous Solution, Funda Sayilkan, Hi̇kmet Sayilkan, Sema Erdemoğlu, Şadi̇ye Şener, Murat Akarsu
Turkish Journal of Chemistry
New adsorbents were synthesized by the sol-gel process from the product of a hydrolysis reaction and its coated form of titanium(IV)-n-propoxide for removing some heavy metal ions from aqueous solution. Titanium(IV)-n-propoxide was uncatalyst hydrolyzed with different amounts of water at room temperature and was found to react in a 1:1.6 ratio (mole of Ti:mole of H_{2}O). It was found that the condensation following the hydrolysis reaction was alcohol condensation. The hydrolysis-condensation product was characterized in detail by GC, Karl-Fischer coulometric titrator, NIR-spectroscopy, FT-IR spectroscopy, TG-DTA and elemental analysis. The hydrolysis-condensation product of titanium(IV)-n-propoxide was calcinated at 900 °C after drying …
Synthesis, Characterization And Applications Of Sol-Gel Derived Zirconium Oxide Adsorbent Powder: Removal From Aqueous Solution Of Phenol And P-Chlorophenol, Murat Akarsu, Hi̇kmet Sayilkan, Şadi̇ye Şener, Funda Sayilkan, Ertuğrul Arpaç
Synthesis, Characterization And Applications Of Sol-Gel Derived Zirconium Oxide Adsorbent Powder: Removal From Aqueous Solution Of Phenol And P-Chlorophenol, Murat Akarsu, Hi̇kmet Sayilkan, Şadi̇ye Şener, Funda Sayilkan, Ertuğrul Arpaç
Turkish Journal of Chemistry
Adsorbent powders were prepared from the uncatalysed hydrolysis-condensation reactions of different complexes that were synthesized by the reactions of Zr(OPr^{n})_{4} with different chelating ligands (such as allylacetic acid [AAH], vinylacetic acid [VAH] and citraconic acid [CAH]). The complex products were characterized by FT-IR, ^{1}H-NMR and ^{13}C-NMR spectra. The maximum combination ratios of AAH/Zr(OPr^{n})_{4}, VAH/Zr(OPr^{n})_{4} and CAH/Zr(OPr^{n})_{4} were 1.7, 0.9 and 1.3, respectively. The hydrolysis-condensation products of these complexes were calcinated at 900 °C and half of them were coated with 3-glycidyloxypropyltrimethoxysilane (GLYMO). The surface area and average pore diameter of the powders were estimated by the analysis of adsorption/desorption BET …
Electrochemical Behaviour Of Thymolphthalein, Mustafa Uçar, Necati̇ Menek
Electrochemical Behaviour Of Thymolphthalein, Mustafa Uçar, Necati̇ Menek
Turkish Journal of Chemistry
The polarographic and voltammetric behaviour of thymolphthalein in ethanol-water (1/5 v/v) was studied using various electrochemical techniques. The reduction of thymolphthalein on a mercury drop electrode was investigated. The adsorption effect on the electrode surface was observed. The rate constants for the electron transfer steps were determined by and without taking adsorption into occount using the Laviron technique and Nicholson technique respectively. The diffusion coefficients were calculated from the cyclic voltammetric data using the method developed by Garrido. Reversibility for the electrode reaction was investigated and a mechanism for the electrode reaction was proposed.
Adsorption Of Arsenate And Chromate From Waters On Hydrophobized Zeolitic Media, Eva Chmielewska
Adsorption Of Arsenate And Chromate From Waters On Hydrophobized Zeolitic Media, Eva Chmielewska
Turkish Journal of Chemistry
A laboratory setup was used to examine the uptake of chromate and arsenate from aqueous solutions by octadecylammonium acetate [ODA]-modified inland clinoptilolite. In trials, a natural variety of montmorillonite was compared to organic, i.e. surfactant loaded clinoptilolite. and some inorganically substituted (Ag, Pb) monoforms. The arrangement of the surface-attached ODA chains was the important factor for differences in the adsorption states of the guest species (oxyanions). A novel nano-structure inorganic-organic composite was prepared and was characterized by SEM, thermogravimetry, HR TEM, UV-VIS diffuse reflectance and powder XRD spectral analytical methods. Finally, the adsorption isotherms of the studied system were expressed. …
Solvent, Temperature And Concentration Effects On The Adsorption Of Poly(N-Butyl Methacrylate) On Alumina From Solutions, Nursel Pekel, Olgun Güven
Solvent, Temperature And Concentration Effects On The Adsorption Of Poly(N-Butyl Methacrylate) On Alumina From Solutions, Nursel Pekel, Olgun Güven
Turkish Journal of Chemistry
Adsorption of poly(n-butyl methacrylate) (PnBMA) on alumina from solution was studied by UV and FT-IR Photoacoustic Spectroscopy techniques. The effects of the solvent, temperature, concentration, and molecular weight of the polymer on adsorption were investigated. Three solvents, cyclohexane, carbon tetrachloride and benzene, were employed. The adsorption was dependent on molecular weight and much more polymer was adsorbed in cyclohexane than in other solvents on the alumina surface. A decrease in adsorption was observed with increasing temperature. The results are in conformity with Langmuir's isotherm. The differences observed in Langmuir parameters were explained by polymer-polymer, polymer-solvent, polymer-adsorbent, and solvent-adsorbent interactions.
Electrochemical Behavior Of Benzo[C]Cinnoline And Its Bromo Derivatives, Ni̇lgün Seçken, M. Levent Aksu, Ali̇ Osman Solak, Emi̇ne Kiliç
Electrochemical Behavior Of Benzo[C]Cinnoline And Its Bromo Derivatives, Ni̇lgün Seçken, M. Levent Aksu, Ali̇ Osman Solak, Emi̇ne Kiliç
Turkish Journal of Chemistry
The electrochemical behavior of benzo[c]cinnoline and some of its bromo derivatives was studied. Two discrete 2-electron reduction waves in acidic and only one wave in basic media in ethyl alcohol-BR buffer system (l:5 v/v) were observed. A mechanism for the electrode reaction is proposed. Diffusion coefficients, formal potentials for and the derivatives, the number of electrons transferred were determined by using sampled current polarography, cyclic voltammetry, chronoamperometry, chronocoulometry and constant potential coulometry. Adsorption of the molecules on the surface of the mercury drop was analyzed and this phenomena was exploited to calculate the formal potentials and the diffusion coefficients of …
Investigation Of The Microporous And Mesoporous Structures Of The Reşadiye (Tokat/Turkey) Bentonite And Its Fractions, Müşerref Önal, Yüksel Sarikaya, Tülay Alemdaroğlu
Investigation Of The Microporous And Mesoporous Structures Of The Reşadiye (Tokat/Turkey) Bentonite And Its Fractions, Müşerref Önal, Yüksel Sarikaya, Tülay Alemdaroğlu
Turkish Journal of Chemistry
It was determined by X-ray diffraction that, besides containing clay minerals such as montmorillonite and illite, the original bentonite contained also clinoptilolite, opal-C, quartz, calcite and dolomite. The original bentonite was separated into four fractions by decantation and precipitation from its aqueous suspension. The adsorption and desorption of nitrogen on the original bentonite and its fractions at 77 K were investigated. The specific surface areas of the samples were determined according to the methods of Brunauer-Emmett-Teller, de Boer-Lippens, and Harkins-Jura by using the adsorption data. The mesopore size distribution curves were plotted by using the desorption data. The specific micropore …
Investigation Of Adsorption Isotherms Of Myristic, Palmitic And Stearic Acids On Rice Hull Ash, Hüseyi̇n Topallar, Yüksel Bayrak
Investigation Of Adsorption Isotherms Of Myristic, Palmitic And Stearic Acids On Rice Hull Ash, Hüseyi̇n Topallar, Yüksel Bayrak
Turkish Journal of Chemistry
The adsorption of myristic, palmitic and stearic acids on rice hull ash from isooctane as solvent was studied and conformed to a Langmuir isotherm. Monolayer coverage was determined to be 40.08, 38.43 and 37.27 mg/g, respectively. The free energy of adsorption, \Delta G°_{ads}, for the adsorption was determined to be -6,25, -6.32 and -6.39 kcal mol^{-1} for the adsorbates, respectively. The equilibrium parameter indicated that rice hull ash is a good adsorbent for myristic, palmitic and stearic acids examined.
Adsorption Of Copper And Cadmium Lons By Activated Carbon From Rice Hulls, Murat Teker, Mustafa İmamoğlu, Ömer Saltabaş
Adsorption Of Copper And Cadmium Lons By Activated Carbon From Rice Hulls, Murat Teker, Mustafa İmamoğlu, Ömer Saltabaş
Turkish Journal of Chemistry
The removal of copper (II) and cadmium (II) ions from aqueous solutions, by adsorption on activated carbon prepared from rice hulls (ACRH), was investigated depending on pH, activated carbon dosage, contact time, initial metal concentration and solution temperature. The optimum values of pH, ACRH dosage and contact time were determined to be 5-8, 0.5 g ACRH/25 mL solution an 60 minutes respctively for the adsorption of Cu (II) ions and 5-8, 1.5 g ACRH/25 mL solution and 60 minutes for the adsorption of Cd (II) ions. From the initial concentrations, the constants for the Freundlich and Langmuir isotherm were calculated …