Nano-hydroxyapatite as an efficient adsorbent for cadmium Removal: Experimental and theoretical insights

El Kaim Billah R., ŞİMŞEK S., BATIR G. G., Katin K., Essenni S., Jugade R., ...Daha Fazla

Journal of Molecular Structure, cilt.1325, 2025 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 1325
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1016/j.molstruc.2024.140712
  • Dergi Adı: Journal of Molecular Structure
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Chemical Abstracts Core, Chimica, Compendex, INSPEC
  • Anahtar Kelimeler: Cd2+removal, DFT, Hydroxyapatite, Kinetics, Thermodynamic
  • Sivas Cumhuriyet Üniversitesi Adresli: Evet

Özet

The presented work aims to investigate the cadmium adsorption on nano-crystalline hydroxyapatite (n-Hap). X ray diffraction (XRD), Fourier transform infra-red (FTIR), Scanning electron microscope (SEM), and Thermogravimetric analysis (TGA) techniques were applied to characterize the n-Hap. Adsorbent mass, pH value, and initial Cd2+concentration were varied to optimize the adsorption conditions. The best Langmuir adsorption isotherm provided equilibrium adsorption capacity of 52.79 mg/g. According to performed kinetic study, the surface reaction fits to the pseudo-second order model. Thermodynamic parameters of the adsorption (∆G°, ∆H° and ∆S°) were derived from the temperature dependence of the adsorption rates. We observed spontaneous endothermic chemisorption of Cd2+ ions. Density functional theory calculations confirmed the spontaneous chemisorption via formation of three Cd-O covalent bonds of about 2.1 Å lengths.