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    Öğe
    Adsorption of nickel(II) ions from aqueous solutions using Malatya clay: Equilibrium, kinetic, and thermodynamic studies
    (Wiley, 2023) Onursal, Nilgun; Altunkaynak, Yalcin; Baran, Ayse; Dal, Mehmet Can
    This paper evaluates Malatya clay (MC) for the removal of Ni(II) ions from aqueous solutions. For adsorption efficiency, the impacts of several factors, such as pH, starting metal ion concentration, and contact duration, were examined. The optimal initial Ni(II) ion concentration was determined to be 5 mg/L, the adsorption contact duration was 360 min, and the solution's pH was 6.27. Using scanning electron microscopy, energy dispersive spectroscopy, and Fourier transform infrared spectroscopy, the surface characteristics of Malatya clay were examined. The isotherm data fit the Langmuir isotherm model, indicating chemical adsorption and likely irreversibility of the process, according to the results. At 298, 308, and 318 K, the adsorption capacities of Ni(II) were determined to be 10.267, 11.834, and 12.285 mg/g, respectively. Adsorption kinetic data revealed that the adsorption of Ni(II) metal ions followed the pseudo-second-order kinetic model. According to thermodynamic studies, Ni(II) ion adsorption on the MC is spontaneous and endothermic. MC has proven to be an effective and alternative material for the removal of Ni(II) ions from aqueous media due to its excellent removal ability, availability, and low cost, as well as its features such as being able to be used without any chemical treatment and being environmentally friendly.
  • [ X ]
    Öğe
    Removal of Ni(II) ions from aqueous solutions with Siirt Kocpinar mixed type clay investigation of isotherm, thermodynamic and kinetic parameters
    (Elsevier Science Inc, 2022) Onursal, Nilgun
    This study used mixed-type clay as an adsorbent to remove Ni(II) ions from the aqueous solution. Crystallographic analyses were performed for crystalloplotic identification. Concentration, temperature, amount of adsorbent, and thermodynamic parameters, which are among the parameters affecting the adsorption, were examined. The obtained data were applied to the Freundlich, Langmuir, Temkin, and Dubinin-Radushkevich adsorption isotherms. It was determined that the data fit the Langmuir adsorption isotherm model the most. The adsorption capacities were determined as 24.81, 29.85 and 58.14 mg/g Ni on clay at 298, 308, and 313 K, respectively. Kinetics data were obeyed to pseudo-second-order. Thermodynamic data (for 298, 308, and 318 K) were calculated as Delta G = -18.569, -20.879, -23.189 kJ/mol, Delta H = 22.60 kJ/mol and Delta S = 0.141 kJ/mol.K, respectively. The Delta H and Delta S values can be obtained directly from the slope and shift of the Gibbs plot presented in this study which is not seen before in the literature. The clay used in the study was chosen due to its low cost and easy acquisition, and as a result of the analysis, it was determined that it could be used as an adsorbent with moderate efficiency in removing Ni(II) ions from water.