Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395

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  • Article
    Citation - WoS: 14
    Citation - Scopus: 14
    Isotherms, Kinetics and Thermodynamics of Pb(II) Adsorption by Crosslinked Chitosan/Sepiolite Composite
    (Springer, 2021-04-13) Senol-Arslan, Dilek
    A novel composite adsorbent was prepared from chitosan (Ch) and sepiolite (S) for removal of Pb(II) from aqueous solution. The Ch-S composite beads were successfully synthesized by crosslinking epichlorohydrin (ECH) and tripolyphosphate (NaTPP). A number of physicochemical parameters such as, pH, initial Pb(II) concentration, temperature, contact time and desorption have been studied during the adsorption process. Experimental data acquired from batch adsorption tests have been analyzed by three isotherm models (Langmuir, Freundlich and Dubinin-Radushkevich), and three kinetic models including the pseudo-first-order, the pseudo-second-order and intraparticle diffusion equations using nonlinear regression technique. Langmuir isotherm was the best to fit the experimental data (R-2 = 0.971). The maximum adsorption capacity was 0.158 mol kg(-1) from Langmuir isotherm model. Maximum removal efficiency was found approximately 66% for the initial Pb(II) concentration of 1000 mg/L, adsorbent dosage of 100 mg and agitation speed of 150 rpm at pH 4.5. The adsorption free energy was found as E-DR (15.8 kJ mol(-1)), which indicated that Pb(II) adsorption process onto Ch-S composite was chemically performed. The kinetic studies have shown that the best fitted kinetic model is the pseudo-first order (R-2 = 0.979). Adsorption enthalpy value was determined as 18.7 kJ mol(-1), adsorption entropy was found as 106 J mol(-1) K-1, and Gibbs free energy was found as 12.9 kJ mol(-1). The thermodynamic parameters showed that the adsorption of Pb(II) on Ch-S was endothermic, possible and spontaneous.
  • Article
    Türkiye’de Farklı Yörelerde Bulunan Kolemanit Minerallerinin Fiziksel, Kimyasal Ve Termal Özelliklerinin Tayini
    (Gumushane University, 2021-08-24) Senol-Arslan, Dilek; Arslan, Dilek Senol; Şenol Arslan, Dilek
    In this study, colemanite is an important boron mineral which constitutes about 76% of Turkey's boron reserves, is frequently used in applications obtained as a result of scientific and technological developments. In this context, a detailed literature survey was carried out colemanite minerals. Characteristic and structural features of the colemanite samples of four different regions (Kestelek, Emet (Hisarcık, Espey), Bigadiç regions) were determined by analyzes such as X-Ray Diffraction (XRD), Inductively Coupled Plasma, ICP and Mass Spectrometry, MS (ICP-MS), Thermogravimetric and Differential thermal analysis (TG-DTA), and Fouier Transform Infrared Spectroscopy (FT-IR) methods. In line with these findings, the mineralogical, chemical and thermal properties of pure colemanite crystals were determined and the similarities and differences between the samples were revealed. © 2025 Elsevier B.V., All rights reserved.