Cu(II) adsorption using a novel oxadiazole-Thione adsorbent: optimization via box–Behnken design
Inorganic Chemistry Communications, cilt.192, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 192
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.inoche.2026.117426
- Dergi Adı: Inorganic Chemistry Communications
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, DIALNET
- Anahtar Kelimeler: Box–Behnken design (BBD), Copper(II) adsorption, Heavy metal removal, Oxadiazole-thione adsorbent
- Kocaeli Üniversitesi Adresli: Evet
Özet
Developing efficient and selective adsorbents for heavy metal removal is essential for sustainable wastewater treatment. In this study, a novel oxadiazole–thione derivative, 4-(4-ethylphenyl)-3-phenyl-1,2,4-oxadiazole-5(4H)-thione (EPPOT), was synthesized and structurally characterized by IR, 1H NMR, 13C NMR, HRMS, and Raman spectroscopy, while its specific surface area was determined by BET analysis. Batch adsorption experiments showed that pH, contact time, and initial Cu(II) concentration substantially influenced removal efficiency. Equilibrium data fitted best to the Freundlich isotherm, indicating heterogeneous surface adsorption. Thermodynamic analysis revealed that the process was spontaneous and weakly exothermic (ΔG° = −8.8 to −9.8 kJ mol−1; ΔH° = −0.86 kJ mol−1), with a positive entropy change (ΔS° = 26.4 J mol−1 K−1).A Box–Behnken Design combined with Response Surface Methodology (RSM) was used to optimize adsorption conditions. The quadratic model was highly significant (F = 94.24, p < 0.0001; R2 ≈ 0.994), identifying pH as the dominant factor. Optimal conditions (pH = 6.0, 75 min, 5 mg L−1 Cu(II)) produced a predicted removal of 85.23%, consistent with the experimental maximum (85.40%). The synthesized EPPOT exhibited rapid and efficient Cu(II) adsorption under mild conditions, demonstrating its potential as an adsorbent for Cu(II) removal from aqueous solutions.