Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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  • Article
    Citation - WoS: 2
    Citation - Scopus: 1
    Cross-Linked Carboxymethyl Cellulose Biosorbent for Zinc Removal: a Sustainable Remediation of Heavy Metal-Polluted Waters
    (Springer Heidelberg, 2025) Celgan, Dilber; Karadag, Asiye; Karim, Barna Jalaluddin Mohammad; Recepoglu, Yasar Kemal; Arar, Ozgur
    This study focuses on the preparation and characterization of cross-linked carboxymethyl cellulose (CMC) biosorbent for efficient removal of Zn2(+) ions from aqueous solutions. The microstructural features of the biosorbent were examined using scanning electron microscopy (SEM), while elemental analysis was conducted using an elemental analyzer to determine carbon (C), hydrogen (H), nitrogen (N), and sulfur (S) content. Fourier transform infrared (FTIR) spectroscopy was employed to identify functional groups within the biosorbent. Sorption experiments revealed that increasing the biosorbent dose led to higher Zn2(+) removal rates until equilibrium was reached. The optimal pH for Zn2(+) removal was determined to be >= 5, attributed to the conversion of acetate group to its ionic form. Rapid kinetics were observed, with 99% removal achieved within 5 min. The biosorbent exhibited a maximum sorption capacity of 10.809 mg/g and a removal rate of 99% at pH 5. Desorption studies demonstrated efficient Zn2(+) recovery using 0.25 M HCl solution, with a total desorption rate exceeding 99%. The findings indicate the potential for cost-effective regeneration of the biosorbent using dilute acid solutions, enhancing its sustainability and practical applicability in water purification processes. Additionally, the biosorbent's selectivity for Zn2(+) ions over competing ions and its effectiveness in treating real water samples, including those containing Na+, K+, Ca2(+), and Mg2(+), highlight its suitability for practical water purification applications.
  • Article
    Citation - WoS: 9
    Citation - Scopus: 10
    Investigation of Reactive Extraction of Monocarboxylic Acids With Menthol-Based Hydrophobic Deep Eutectic Solvent by Response Surface Methodology
    (Taylor & Francis Inc, 2023) Yıldız, Esra; Lalikoğlu, Melisa; Aşçı, Yavuz Selim; Sırma Tarım, Burcu
    The growing demand for producing organic acids by fermentative techniques has increased the significance of separating carboxylic acids from their fermentation broth with the reactive extraction process. Considering the environmental impacts, deep eutectic solvents can be considered as a potential green alternative for the replacement of volatile organic solvents commonly used in the extraction process. In this study, a new type of green solvent named hydrophobic deep eutectic solvent (HDES) based on decanoic acid as a hydrogen bond acceptor and menthol as a hydrogen bond donor was utilized for the reactive extraction of formic, acetic, and propionic acids from their aqueous solutions. The effect of initial acid concentration, HDES molar ratio, and tri-n-octyl amine (TOA) concentration on extraction efficiency was investigated. Modeling of the reactive extraction process was performed via a response surface methodology with a central composite design. Herein, the effect of the parameters of TOA concentration, HDES molar ratio, and initial acid concentration on the distribution coefficient was investigated. According to the results, it was reported that the most effective parameter on the extraction efficiency (%E) was the amount of extractant. The results of the experimental studies showed that the highest separation efficiency was obtained for 5% initial concentrations of formic, acetic, and propionic acids by using a mixture of 0.5 HDES molar ratio solvent and 1.9 mol/L TOA. The extraction efficiencies of these acids were found to be 88.71, 92.52, and 95.90 with +/- 0.1 standard deviation, respectively.
  • Conference Object
    Citation - Scopus: 1
    Fs Fbgs as Probes To Monitor Thermal Regeneration Mechanisms
    (SPIE, 2019) Chah, K.; Kinet, D.; Yüksel, Kıvılcım; Caucheteur, C.
    This paper shows that fiber Bragg gratings written in standard single mode optical fiber with IR femtosecond pulses and point-by-point technique are high temperature resistant (< 1000 degrees C). Moreover, after calibration process, these gratings can be used as a reference to study and discriminate between different high temperature annealing mechanisms involved in other types of gratings and/or fibers. Here we have considered the regeneration process of gratings written by UV laser in boron/germanium co-doped single mode optical fiber. Hence, the monitoring of grating strength and differential wavelength shift between femtosecond and type-I gratings during annealing cycle yields the wavelength shift due to the annealing of doping (mainly boron) and UV-related defects and their relative contributions to the regeneration mechanism.
  • Article
    Citation - WoS: 55
    Citation - Scopus: 60
    Effect of Regeneration Temperature on Adsorption Equilibria and Mass Diffusivity of Zeolite 13x-Water Pair
    (Elsevier Ltd., 2016) Sayılgan, Şefika Çağla; Mobedi, Moghtada; Ülkü, Semra
    The adsorption equilibrium and mass diffusivity of zeolite 13X-water pair for different adsorption and regeneration temperatures were determined by a homemade volumetric system. The isotherms of the zeolite 13X-water pair were obtained by collecting pressure versus time data and applying ideal gas law. The effective diffusivity of the pair was calculated by using long term analytical solution of mass diffusivity based on Fick's law. The experimental study showed that the adsorption capacity of zeolite 13X-water pair was 23% (kg/kg), 21% (kg/kg) and 19% (kg/kg) when the adsorption temperature was 35, 45 and 60 °C respectively for the desorption temperature of 90 °C. Furthermore, the adsorption capacity increased from 22% (kg/kg) to 24% (kg/kg) when the desorption temperature was increased from 90 °C to 150 °C. It was observed that the present adsorption equilibrium results were compatible with the reported results in the literature. The mass diffusivity of the pair was found in the range of 4 × 10-9-6 × 10-8 m2/s for the long time period when the initial adsorptive pressure was 2000 Pa. The effective mass diffusivity depends on concentration and it was decreased with increasing adsorbate concentration.
  • Article
    Citation - WoS: 56
    Citation - Scopus: 59
    Suzuki Cross-Coupling Reaction of Aryl Halides With Arylboronic Acids Catalysed by Pd(ii)-Nay Zeolite
    (Elsevier Ltd., 2003) Bulut, Hatice; Artok, Levent; Yılmaz, Selahattin
    Pd(II)-exchanged NaY zeolite showed high activity in the Suzuki cross-coupling reactions of aryl bromides and iodides without added ligands. The DMF:water ratio, and the type and amount of base were found to be critical for the efficiency of the reaction. The catalyst is reusable after regeneration.