DSpace Arşivi :: by Yazar "Tegin, Ibrahim" değerine göre listeleniyor

Yazar "Tegin, Ibrahim" seçeneğine göre listele

Listeleniyor 1 - 20 / 29

A broad assessment of Eremurus spectabilis M. Bieb: chemical and elemental composition, total phenolic and antimicrobial activity analysis, and quantum chemical calculations of radical scavenging potential
(Taylor & Francis Ltd, 2024) Tegin, Ibrahim; Hallac, Bulent; Sabanci, Nazmiye; Sadik, Betul; Fidan, Mehmet; Yabalak, Erdal
Eremurus spectabilis M. Bieb was extensively investigated experimentally and theoretically, including the antioxidant properties of compounds such as flavonoids, hydroxycinnamic acid derivatives, hydroxybenzoic acid derivatives, and organic acids. Antioxidant activity was investigated using the Density Functional Theory (DFT) method based on three known mechanisms: hydrogen atom transfer (HAT), single electron transfer followed by proton transfer (SET-PT), and sequential proton loss electron transfer (SPLET). Subcritical water extraction (SWE), soxhlet extraction (SE), and solvent extraction (SOE) techniques were applied in the extraction process. Malic acid was the major compound with an extract concentration of 38,532.84 +/- 1849.58 mu g analyte/kg, total phenolics, and free radical scavenging activity were 10.67 mg gallic acid/mL extract and 73.89% per mg/mL extract, respectively. P, Fe, Na, Mg, K, and Ca were the main elements. The antibacterial activity of E. spectabilis against seven bacteria was evaluated, and it was found to be higher than the commercial antibiotics P10 and AMC30.
Adsorption of copper (II) from aqueous solutions using adsorbent obtained with sodium hydroxide activation of biochar prepared by microwave pyrolysis
(Springer Heidelberg, 2024) Tegin, Ibrahim; Oc, Sema; Saka, Cafer
Microwave heating is one of the leading methods that save energy, time, and cost for the conversion of bio-waste into biochar in the agricultural sector. In this study, in the first stage, economical biochar production from pistachio green hulls by microwave heating method is in question. In the second step, sodium hydroxide(NaOH) activation was followed to improve the surface properties of biochar. This adsorbent obtained was applied to remove copper ions(Cu(II)) from wastewater. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), thermogravimetry differential thermal analysis (TG/DTG), and nitrogen adsorption/desorption methods were used to characterize the biochar samples. In adsorption studies, kinetic, isotherm, and thermodynamic parameters were investigated. Cu(II) adsorption capacity on modified biochar obtained by Langmuir isotherm was found to be 227.27 mg/g. In addition, the mechanism of Cu(II) adsorption on modified biochar has been proposed. Biochar, which is obtained from the green shells of pistachios, which is widely available and grown in Turkey, by microwave method and then NaOH activation, is a potential solution for both the improvement of water pollution caused by heavy metals and the disposal of related wastes with an appropriate method.
Alterations of Serum Copper and Zinc Levels, and Copper/Zinc Ratios Among Patients with Brucellosis
(Ortadogu Ad Pres & Publ Co, 2012) Ustun, Cemal; Tegin, Ibrahim; Geyik, Mehmet Faruk
Objective: To determine the alterations of serum copper (Cu) and zinc (Zn) levels and Cu/Zn ratio in patients with brucellosis. Material and Methods: A total of 170 individuals were included in the study. Of these, 45 (26.5%) currently had acute or sub-acute brucellosis, 35 (20.6%) were previously diagnosed with acute or sub-acute brucellosis and successfully treated, and 90 (52.9%) were healthy volunteers. After fasting overnight for 10 hours, 5 ml of venous blood was taken from all subjects. Serum Cu and Zn levels were measured using a Unicam 929 Atomic Absorption Spectrophotometer. SPSS 16.0 was used for data analysis. Results: Mean serum Cu levels of 45 patients with acute or sub-acute brucellosis, 35 patients previously diagnosed with acute or sub-acute brucellosis and 90 healthy volunteers were 88.6 +/- 26, 58.7 +/- 13 and 56.7 +/- 16 mu g/dL, respectively. Mean serum Zn levels of 45 patients with acute or sub-acute brucellosis, 35 patients previously diagnosed with and treated successfully for acute or sub-acute brucellosis and 90 healthy volunteers were 38.3 +/- 12, 58.5 +/- 14, and 55.8 +/- 13 mu g/dL, respectively. Serum Cu levels (p<0.001) and Cu/Zn ratios (p<0.001) were statistically significantly higher while serum Zn levels (p<0.001) were lower in patients with acute or sub-acute brucellosis when compared to the individuals who previously diagnosed with acute or sub-acute brucellosis and the healthy volunteers. Conclusion: This study revealed significant alterations of serum Cu and Zn levels, and Cu/Zn ratios in patients with acute or sub-acute brucellosis. Serum Cu, Zn, and Cu/Zn ratios may be available biomarkers in the course of acute or sub-acute brucellosis.
Analytical methods for determination of selective serotonin reuptake inhibitor antidepressants
(Walter De Gruyter Gmbh, 2011) Senturk, Zuhre; Saka, Cafer; Tegin, Ibrahim
Selective serotonin reuptake inhibitors (SSRIs) are commonly used to treat depression. SSRIs are classified as fluoxetine, paroxetine, escitalopram, citalopram, sertraline, and fluvoxamine. Several methods have been published for the determination of SSRI drugs in pharmaceuticals, biological materials and environmental samples. This review covers the analytical methods described in the literature for the determination of SSRIs and their main metabolites or some compounds belonging to the same SSRI group. The analytical methods are generally chromatography based methods coupled to different detectors, electroanalytical methods, capillary zone electrophoretic methods, and spectrometric methods.
The antioxidant capacity, total phenolic content and phenolic compounds of Spergularia rubra (L.) J. Presl & C. Presl in naturally distributed five different saline areas in Siirt province
(IEEE, 2018) Tegin, Ibrahim; Canpolat, Gurbet; Fidan, Mehmet
Spergularia rubra has a very wide spread in the world. Infusion of S. rubra is used for diuretic purposes. Although widely used, the antioxidant activity of this species has not been evaluated and its chemical composition is not known [1]. In this study, antioxidant activity (DPPH %), total phenolic content (Folin Ciocalteau method) and phenolic compounds profile (LC-MS/MS) of methanolic extract of Spergularia rubra plant that collected from five different localities in Siirt were analyzed. According to the results of the analysis, the total phenolic content range from 4.33 to 13.16 mg gallic acid/mL extract. The highest antioxidant activity value was found as 77.70 %, on the other hand, the lowest was found as 57.32 %. As a result of the LC- MS/MS analysis for Cöl (Bayraktepe), location, 18 phenolic compounds were quantitatively and qualitatively determined, among the 27 phenolic compounds. The all values obtained (μg analyte/kg extract) were as follows; Quinic acid (4788.53±229.85), Malic acid (9618.56±509.78), tr-Aconitic acid (96.76±4.74), Gallic acid (141.54±7.22), Protocatechuic acid (56.17±2.86), Tannic acid (6068.41±309.49), tr-Coffeic acid (2.55±0.13), Vanilin (30.02±1.47), p-Coumaric acid (48.64±2.48), Rutin (1.13±0.05), Hyperoside (4.47±0.2), 4-OH benzoic acid (9.26±0.4), Salicylic acid (13.3±0.6) Kaempferol (63.68±3.31), Naringenin (2.33±0.12), Luteolin (35.12±2.42) Apigenin (35.14±1.86) and Rhamnetin (29.28±1.78).
Assessment of trace element and quality parameters in sheep milk from different regions and different seasons in the Iraqi Kurdish region
(Taylor & Francis Ltd, 2023) Tegin, Ibrahim; Dawdy, Gazee Rahman Muhamad; Hallac, Bulent; Yabalak, Erdal
Trace elements found in sheep milk are present as inorganic ions and their salts as part of organic molecules such as proteins, fats, carbohydrates and nucleic acids. The chemical form of trace elements found in milk is important as it determines their absorption and biological utilisation in the intestine. In this study, trace element concentration and quality of sheep milk were evaluated in a total of 97 sheep milk samples collected from different regions (Erbil, Altunkopri, Makhmur, Qaraj, Kasnazan, Khabat, Taqtaq, Koysinjaq, Soran, Rawanduz and Sidakan) in the Iraqi Kurdish region during two seasons in April and September. Flame atomic absorption spectroscopy (FAAS) was used to analyse the element content of the samples. The results in the samples collected in both periods showed that the mean values of Na, K, Ca, Mg, Zn, Pb, Cr, Fe, P, Se and Cu were 328.15 mu g mL-1, 1604.40 mu g mL-1, 805.8 mu g mL-1, 177.28 mu g mL-1, 0.38 mu g mL-1, 0.67 mu g mL-1, 3.15 mu g mL-1,0.08 mu g mL-1, 260.04 mu g mL-1, 0.06 mu g mL-1, and 3.83 mu g mL-1, respectively. The mean values for some quality parameters such as fat, density, lactose, total salt and protein of sheep milk samples collected in both periods were 6.47%, 1029.28 kg m-3, 4.44%, 9.01%, and 4.07%, respectively. Besides, the data obtained were evaluated by some chemometric techniques such as correlation, multicomponent analysis (PCA) and cluster analysis (CA).
Chemical and thermal activation of clay sample for improvement adsorption capacity of methylene blue
(Taylor & Francis Ltd, 2023) Tegin, Ibrahim; Saka, Cafer
In this study, the removal of methylene blue (MB) by both raw and modified clay as an abundant, cost-effective was investigated. The modification of the raw clay was done by calcination, acid treatment, and again second calcination processes. In addition, the effects of calcination temperature and acid/base concentration on the adsorption capacity of clay were investigated. The characterisation of clay was performed by scanning electron microscopy (SEM) and Fourier transformed infrared spectroscopy (FTIR) analyzes. Langmuir and Freundlich isotherm models were used. The modified clay provided significant improvements in adsorption capacity compared to the raw clay.
Determination of pesticide residues in varieties of pepper sold at different periods and provinces in Turkey and investigation of their adverse effects on human health and the environment
(Taylor & Francis Ltd, 2024) Aktas, Serafettin; Aminzai, Mohammad Tahir; Tegin, Ibrahim; Yabalak, Erdal; Acar, Orhan
Pesticides are dangerous chemicals that can harm to people and the environment when applied inappropriately or in excess. In this research, various pesticide residues were investigated in 48 pepper samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). All samples were collected randomly in two periods of time (September and December) from markets and greengrocers in four provinces (Siirt, Mardin, Diyarbakir, and Batman). Considering the means of the first and second periods, diclofop-methyl had the highest concentration of 29.4 & PLUSMN; 7.7 & mu;g kg-1, and diazinon had the lowest of 21.1 & PLUSMN; 4.6 & mu;g kg-1. Based on the maximum residue limits (MRLs) of pesticides specified in the Turkish Food Codex, pyrimethanil, bupirimate, and diclofop-methyl were found to be below the maximum acceptable residue limit, while pyridaphention, dinoseb, diazinon, and pirimiphos-methyl were found to be above the limit. Thus, the current study demonstrated the potential of LC-MS/MS as a crucial technique for accurate measurements and confirmations of pesticides in different pepper varieties.
EVALUATION OF CHEMICAL CONTENT AND RADICAL SCAVENGING ACTIVITY OF ALLIUM VINEALE L. EXTRACT AND ITS ELEMENTAL ANALYSIS
(Editura Acad Romane, 2019) Tegin, Ibrahim; Yabalak, Erdal; Sadik, Betul; Fidan, Mehmet
Allium vineale L. was extensively analysed to determine its radical scavenging activity, chemical composition, total polyphenol content, and elemental composition. The Soxhlet and the subcritical water extraction methods were performed for the extraction procedure. The extracts obtained in the subcritical water extraction method were evaluated by GC-MS. 11 compounds were determined according to mass spectral libraries of GC-MS, Wiley7Nist05.L, NIST05a.L, W9N11.L. The obtained compounds were evaluated for their benefits on health according to literature. DPPH inhibition of Allium vineale L. was obtained as 58.60 % and the total polyphenol content of Allium vineale L. was obtained as 12 mu g/mL gallic acid equivalent. 28 elements were obtained in the elemental analysis by ICP-MS, using the microwave digestion procedure. UHPLC-ESI-MS/MS analysis was performed for the evaluation of methanolic extract of Allium vineale L. obtained in the Soxhlet extraction method.
Exploring Sustainable Pb Recovery from Zinc Plant Residues via Hydrometallurgical Processes: Comparative Analysis of Zinc and Aluminum Powder Cementation
(Springer Int Publ Ag, 2024) Holagh, Mohsen Valizadeh; Tegin, Ibrahim; Yabalak, Erdal
This study explores the recovery and preparation of Pb from Zn plant residues (ZPR), specifically leaching filter cake (LFC), through a hydrometallurgical process that includes the cementation of Pb using Zn and Al powder. The process consists of three key stages: acidic washing of zinc, alkali leaching, and the subsequent cementation of lead using zinc and aluminum powder. The effects of various parameters such as powder amount, temperature, reaction time, and stirring speed on the reaction kinetics were systematically examined. Optimal separation conditions were determined for both zinc and aluminum powder, with Pb cementation achieving 97.56% and 99.95% respectively, under specific conditions. Additionally, a kinetic study was conducted to evaluate the reaction mechanisms and activation energies associated with Pb cementation using zinc and aluminum powder. The results indicated that Pb cementation was powder-controlled in both cases, with reaction activation energies of 8.6 kJ/mol and 4.6 kJ/mol using zinc and aluminum powder, respectively. Furthermore, the use of aluminum powder demonstrated several advantages including enhanced performance, high purity of Pb product, and reduced powder consumption. This research advances the optimization and understanding of Pb recovery processes from ZPR, emphasizing the potential of aluminum powder as a promising alternative for effective lead cementation.
Facile hydrogen peroxide modification of activated carbon particles produced by potassium hydroxide activation for removal of heavy metals from aqueous solutions
(Elsevier Science Sa, 2023) Murtazaoglu, Cetin; Tegin, Ibrahim; Saka, Cafer
Here, the activated carbon (AC) was first produced by potassium hydroxide (KOH) activation from pistachio shells. Subsequently, the obtained AC was modified with hydrogen peroxide (H2O2) activation. Cu (II) and Zn (II) ions adsorption using the KOH-AC-H2O2 was carried out from wastewater. The correlation coefficient (R2) values in the adsorption of KOH-AC-H2O2 and Cu (II) and Zn (II) showed compliance with the Langmuir isotherm model. The maximum adsorption capacities (Qm) with Cu (II) and Zn (II) from the Langmuir isotherm model at 30 degrees C for KOH + AC-H2O2 were 212.76 mg/g and 12.00 mg/g, respectively. The pHpzc of the H2O2-modified adsorbent was 7.58. However, the pHpzc of the KOH-AC adsorbent was 8.82 The resulting KOH-AC and KOH-ACH2O2 samples were characterized by X-Ray diffraction (XRD), thermogravimetric/differential (TG-DTA), scanning electron microscope (SEM), Fourier transforms infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS), and nitrogen adsorption/desorption analyses. SEM analyses confirmed that the surface of the AC samples obtained was highly porous. At the same time, FTIR and EDS analyses showed the formation of oxygenated groups on the AC surface. In the kinetic experiments, the pseudo-second-order model was suitable for the adsorption of Cu (II) and Zn (II). The low-cost and environmentally friendly adsorbent obtained as a result of the modification of H2O2 with KOH-AC has improved the removal ability of heavy metals.
Facile modification strategies on hydrochar-based carbon particles with hydrothermal carbonization from green pistachio hulls for the removal of cadmium ions from aqueous solutions
(Springer Heidelberg, 2023) Oc, Sema; Tegin, Ibrahim; Yabalak, Erdal; Saka, Cafer
The aim of this study is based on the efficient removal of cadmium ions (Cd2+) from aqueous solutions with the adsorbent obtained by various modification strategies on hydrochar-based carbon particles obtained by hydrothermal carbonization from green pistachio hulls as a precursor. Hydrochloric acid (HCl), sodium hydroxide (NaOH), or phosphoric acid (H3PO4) were used to functionalize the surface to increase the adsorption capacity of hydrochar. Maximum Cd2+ adsorption capacity from environmental waters by PHHC-NaOH hydrochar at 298 K was found to be 526.31 mg/g. Surface morphology and chemical compositions of hydrochar were investigated by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), energy-dispersive spectroscopy (EDS), and thermogravimetric/differential (TG-DTA) and nitrogen adsorption/desorption analyses. Isotherm, kinetic, and thermodynamic properties were evaluated in detail. Also, possible mechanisms for Cd2+ binding on modified hydrochar were evaluated.
Facile phosphorus and oxygen heteroatom functionalization of biochar based on biomass prepared by microwave pyrolysis for adsorption process of cadmium in aqueous solution
(Springer Heidelberg, 2024) Tegin, Ibrahim; Oc, Sema; Saka, Cafer
In this study, in the first stage, biochar is produced from green pistachio hulls (PGHMAC) by microwave heating method, which saves energy, time and cost. In the second step, with the activation of phosphoric acid (H3PO4), the surface properties of the biochar were modified by phosphorus (P) and oxygen (O) doping (O- and P-doped PGHMAC). This adsorbent obtained was applied to remove cadmium (Cd(II)) from wastewater. FTIR, SEM, EDX, and ICP-OES analyses were used for the characterization of the samples. FTIR, EDX, and ICP-OES analysis results showed the presence of oxygen and phosphorus groups on the surface of the relevant adsorbent. The contents of C and O atoms for P- and O-doped PGHMAC were found to be 62.54% and 36.12%, respectively. Also, about 1.29% of P atoms were found with H3PO4 activation. The kinetic, isotherm, and thermodynamic parameters of the adsorption studies were investigated. Maximum Cd(II) adsorption capacities of P- and O-doped PGHMAC at 298 K, 308 K, and 318 K temperatures were calculated as 78.74, 109.89, and 133.33 mg/g by Langmuir model, respectively. The mechanism of Cd(II) adsorption on O- and P-doped PGHMAC has been proposed.
Investigation of the effectiveness of waste nut shell-based hydrochars in water treatment: a model study for the adsorption of methylene blue
(Springer Heidelberg, 2024) Tegin, Ibrahim; Demirel, Mehmet Ferit; Alacabey, Ihsan; Yabalak, Erdal
Thousands of tons of walnut and pistachio green outer shells emerge as waste sources. Recycling such wastes in environmental applications is of great importance. In this study, the efficiency of waste walnut and pistachio shell-based hydrochars in removing methylene blue (MB), which represents hazardous chemicals, from the water was investigated. Outer green pistachio shell-based hydrochar (PH) and outer green walnut shell-based hydrochar (WH) were characterized by FT-IR, SEM, EDX, TG-DTA, and BET analyses. The adsorption of MB was carried out at different concentrations and temperatures using WH and PH, and the adsorption parameters of Langmuir and Freundlich were investigated. The R-2 values of PH were calculated as 0.9963, 0.9974, and 0.9950 and of WH adsorbent were calculated as 0.9759, 0.9939, and 0.9981 for the MB adsorption at 298 K, 313 K, and 323 K, respectively. The separation factor (R-L) values for WH and PH were calculated as 0.1650 >= R-L >= 0.103, 0.1108 >= R-L >= 0.0177, respectively. Both adsorbents fit the Langmuir model. The Delta H degrees values of the WH and PH adsorbents were found to be 37.0940 and 22.2493, respectively. Positive Delta H degrees values indicated that the adsorption was endothermic. The negative Delta G degrees values of both adsorbents indicated a spontaneous adsorption process. It was shown that waste nut shell-based hydrochars can be used effectively in water treatment.
Nitrogen- and oxygen-doped carbon particles produced from almond shells by hydrothermal method for efficient Pb(II) and Cd(II) adsorption
(Springer Heidelberg, 2024) Saka, Cafer; Tegin, Ibrahim; Kahvecioglu, Kubra; Yavuz, Omer
In this study, a two-step method was applied to obtain an effective adsorbent for cadmium (Cd) (II) and lead (Pb)(II) adsorption. The first stage includes the production of activated carbon (AC) from almond shells, which is agricultural waste, by microwave heating and potassium hydroxide (KOH) chemical agent. The second stage includes nitrogen and oxygen doping by hydrothermal heating treatment of the obtained ACs with nitric acid. The obtained materials were characterized by thermogravimetric/differential thermal analyser (TG-DTA); Fourier transform infrared spectroscopy (FTIR); scanning electron microscope (SEM); energy-dispersive spectroscopy (EDS); C, H, N, S elemental analysis; and nitrogen adsorption analyses. The adsorption performance, mechanism, kinetics, and thermodynamics of nitrogen- and oxygen-doped activated carbons were evaluated. The obtained isotherm and kinetic results showed that the adsorption of Cd (II) and Pb (II) on nitrogen- and oxygen-doped ACs followed Langmuir isotherm and pseudo-second-order kinetics. The adsorption capacity values (Qm) obtained for Cd (II) and Pb (II) adsorption were 106.38 mg/g and 76.33 mg/g, respectively.
Phosphorus and oxygen co-doped carbon particles based on almond shells with hydrothermal and microwave irradiation process for adsorption of lead (II) and cadmium (II)
(Springer Heidelberg, 2023) Kahvecioglu, Kubra; Tegin, Ibrahim; Yavuz, Omer; Saka, Cafer
In this study, the production of activated carbon based on almond shells by microwave heating with KOH activation and then the modification of activated carbon with phosphorus and oxygen as a result of hydrothermal heating with phosphoric acid were carried out to increase the Cd(II) and Pb(II) adsorption efficiency. The resulting materials were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric/differential thermal analyzer (TG-DTA), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and nitrogen adsorption. Adsorption performance, kinetics and thermodynamics of phosphorus, and oxygen-doped activated carbons were evaluated. The results showed that the adsorption of both Cd(II) and Pb(II) on phosphorus and oxygen-doped activated carbons obeyed the Langmuir isotherm and pseudo-second-order kinetics. The adsorption capacity values (Q(m)) obtained from the Langmuir isotherm for Cd(II) and Pb(II) adsorption were 185.18 mg/g and 54.64 mg/g, respectively. At the same time, the adsorption mechanism of Pb(II) and Cd(II) on the respective adsorbents was evaluated. As a result of phosphorus and oxygen atoms, Lewis base sites on carbon atoms and Lewis acid sites on phosphorus atoms are likely to form on the surface. These Lewis base sites can act as important active sites in adsorption reactions, especially of positively charged Pb(II) and Cd(II) ions.
Phosphorus-doped porous carbon particles based on biomass for efficient adsorption performance of Cu2+ and Zn2+ from aqueous solutions: thermodynamics, isotherms, kinetics, and mechanism
(Springer Heidelberg, 2023) Saka, Cafer; Tegin, Ibrahim; Murtazaoglu, Cetin
In this study, the fabrication of two-step phosphorus-doped porous carbon particles for adsorbent design based on low-cost biomass is performed for heavy metal removal. In the first step, activated carbon is produced from pistachio shells as biomass by activation of potassium hydroxide (KOH) (PSAC/KOH). In the second step, as a result of the activation of the obtained PSAC/KOH with phosphoric acid (H3PO4), phosphorus (P)-doped PSAC/KOH is obtained. Removal of Cu2+ and Zn2+ ions from environmental waters is carried out with P-doped PSAC/KOH. EDS, ICP-OES, and FTIR analyses showed that the P atom was doped on the AC surface. It is possible that the absorption of Cu2+ and Zn2+ will increase with the complexes that may form between the phosphorus-containing groups of the modified sample and the metal ions. For P atoms are less electronegative than C atoms, in possible C-P bonds, the P atom will have a positive charge density and the carbon atoms will have a negative charge density. Thus, Lewis base sites are formed on carbon atoms. Lewis base sites serve as important active sites in this adsorption application. The maximum adsorption capacities (Qm) of 136.38 mg/g and 12.57 mg/g at 30 degrees C of Cu2+ and Zn2+ removal are obtained with P-doped PSAC/KOH, respectively.
Removal and Preconcentration of Pb(II), Cr(III), Cr(VI) from the Aqueous Solution and Speciation of Cr(III)-Cr(VI) by Using Functionalized Amberlite XAD-16 Resin with Dithioethylenediamine
(Asian Journal Of Chemistry, 2010) Dolak, Ibrahim; Tegin, Ibrahim; Guzel, Remziye; Ziyadanogullari, Recep
Amberlit XAD-16 was functionalized using dithioethylenediamine as a ligand and characterized by elemental analysis and FTIR spectroscopy. The effects of contact time, pH, electrolyte and the concentration of eluent on separation and preconcentration of Pb(II), Cr(III) and Cr(VI) were studied. In addition, the batch capacity for each ion was determined under the optimum conditions. The preconcentration yields of Pb(II), Cr(III) and Cr(VI) were found to be 96.60 +/- 3.02, 102.20 +/- 3.00 and 100.64 +/- 2.24 %, respectively, with 500 times preconcentration factor under the optimum conditions. The speciation of Cr(III)-Cr(VI) was studied, it was determined that Cr(III) separated in 93.24 +/- 2.21 % yield from the solution containing Cr(III)-Cr(VI) by using Amberlit XAD-16-dithioethylenediamine and Cr(VI) remained in the solution at pH 4, while Cr(VI) separated in 101.43 +/- 3.09 % yield from the solution containing Cr(III)-Cr(VI) and Cr(III) remained in the solution. at pH 7.50 by using Amberlit XAD-16-dithioethylenediamine-Pb(II).
Removal and Preconcentration of Pb(II), V(V), Cr(VI) from the Aqueous Solution and Selective Separation of V(V)-Cr(VI) by Using Functionalized Amberlite XAD-16 Resin with Dithioethylenediamine
(Asian Journal Of Chemistry, 2010) Dolak, Ibrahim; Tegin, Ibrahim; Guzel, Remziye; Ziyadanogullari, Recep
Amberlit XAD-16 was functionalized using dithioethylenediamine as a ligand. and characterized by elemental analysis and FTIR spectroscopy. The effects of contact time, pH, electrolyte and the concentration of eluents on separation and preconcentration of Pb(II), Cr(VI) and V(V) were studied. In addition, the batch capacity for each ion was determined under the optimum conditions. The preconcentration yields of Pb(II), Cr(VI) and V(V) were found to be 96.60 +/- 3.02, 100.64 +/- 2.24 and 98.20 +/- 3.00 %, respectively, with 500 times preconcentration factor under the optimum conditions. The selective separation of Cr(VI)-V(V) was studied in terms of pH. It was determined that V(V) separated in 98.24 +/- 1.21 % yield from the solution containing Cr(VI)-V(V) and Cr(VI) remained in the solution at pH 2.5, while Cr(VI) separated in 101.43 +/- 3.09 % yield from the solution containing Cr(VI)-V(V) and V(V) remained in the solution at pH 8.5 by using Amberlit XAD-16-dithioethylenediamine -Pb(II).
Sulphur-doped carbon particles from almond shells as cheap adsorbent for efficient Cd(II) adsorption
(Elsevier Science Sa, 2023) Saka, Cafer; Tegin, Ibrahim; Kahvecioglu, Kubra
One of the ways to increase the adsorption capacity of carbon-based materials is to add heteroatoms. However, the use of sulphur-doped carbons is quite limited. This study includes the production of activated carbon (AC) from almond shells by microwave heating and KOH chemical agent and sulphur doping by hydrothermal heating treatment of the obtained ACs with sulphuric acid for Cd(II) adsorption. The thermogravimetric/differential thermal analyser (TG-DTA), Fourier transforms infrared spectroscopy (FTIR), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and nitrogen adsorption analyses were performed for character-ization. For KOH-MA-S, the FTIR spectra peaks associated with the S--O stretching vibration appeared at approximately 1153 cm-1 and 1024 cm -1. The SEM image of the KOH + MA + S sample shows that a het-erogeneous and layered structure is formed again due to the collapse or coalescence of the pores with the hy-drothermal sulphuric acid activation on the carbonaceous surface. While there is almost no sulphur in the KOH-MA sample, there is approximately 9 % sulphur in the KOH-MA-S sample in the EDS results. The adsorption performance, kinetics, thermodynamics and mechanism for Cd(II) adsorption on sulphur doped ACs were evaluated. The isotherm and kinetic results showed that Cd(II) adsorption on sulphur-doped AC fits the Langmuir isotherm and pseudo-second-order kinetics with high correlation values. The adsorption capacity values (Qm) obtained for Cd(II) adsorption were 282.70 mg/g.

Yazar "Tegin, Ibrahim" seçeneğine göre listele

Sayfa Başına Sonuç

Sıralama seçenekleri