Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
Browse
2 results
Search Results
Article Citation - WoS: 29Citation - Scopus: 34Preparation and Characterization of a Novel Diatomite-Based Composite and Investigation of Its Adsorption Properties for Uranyl Ions(Springer, 2019-07-20) Senol, Zeynep Mine; Arslan, Dilek Senol; Simsek, Selcuk; Şenol Arslan, DilekIn this research, Polyacrylamide-diatomite (PAA-D) composite was used as adsorbent for the efficient removal of uranyl ions from aqueous solution. The chemical and morphological properties of PAA-D composite were confirmed by several analysis. Batch experiments were performed as a function of solution pH, initial concentration, kinetic, thermodynamic and recovery. The maximum metal uptake capacity was found as 0.085 mol kg(-1). Kinetic data were best interpreted by a pseudo second order model. Thermodynamic findings showed that the adsorption process was exothermic, spontaneous and process with increased disorderliness at solid/solution interface. The recovery studies showed that PAA-D composite had good adsorption/desorption performance.Article Citation - WoS: 14Citation - Scopus: 14Isotherms, Kinetics and Thermodynamics of Pb(II) Adsorption by Crosslinked Chitosan/Sepiolite Composite(Springer, 2021-04-13) Senol-Arslan, DilekA 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.