Scholarlink

<p>The persistent contamination of water by cadmium (Cd<sup>2</sup>⁺) and copper (Cu<sup>2</sup>⁺) poses acute risks to human health and ecosystems, and continues to challenge conventional treatment technologies. In this study, a rationally designed hydrazone-based ligand, H₂L(A3), enriched with nitrogen and oxygen donor sites, was synthesized and evaluated as a selective sorbent for Cd(II) and Cu(II) removal from aqueous media. The material was rigorously characterized using elemental analysis, mass spectrometry (MS), Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), X-ray diffraction (XRD), Brunauer–Emmett–Teller/ Barrett–Joyner–Halenda (BET/ BJH) surface area analysis, dynamic light scattering (DLS), zeta potential (ζ), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM–EDX), and thermogravimetric analysis (TGA). These techniques confirmed the ligand’s molecular identity, heteroatom-rich surface, mesoporous texture (2–4 nm), moderate surface area (~ 54 m<sup>2</sup> g⁻<sup>1</sup>), submicron dispersion, and thermal stability. Batch adsorption studies explored the effects of pH, dose, contact time, temperature, and initial concentration, with data interpreted using nonlinear kinetic (pseudo-first-order, pseudo-second-order, intraparticle diffusion), isotherm (Langmuir, Freundlich, Temkin, D-R, Sips), and thermodynamic (van’t Hoff) models. H₂L(A3) exhibited high monolayer adsorption capacities (qₘₐₓ) of 108.3 mg g⁻<sup>1</sup> for Cd(II) and 83.4 mg g⁻<sup>1</sup> for Cu(II), reflecting strong affinity and preferential interaction with Cd(II). Adsorption was spontaneous and exothermic (ΔG°, ΔH° &lt; 0; ΔS° &lt; 0), indicating an electrostatically assisted chemisorption process dominated by inner-sphere coordination on N, O donor sites. Regeneration with 1.0 M nitric acid (HNO₃) achieved 90–94% desorption, with ≥ 75% efficiency retained after three cycles. Importantly, in real wastewater matrices containing competing ions, H₂L(A3) maintained selective removal performance, achieving 49.2% Cd(II) and 23.8% Cu(II) removal. These results confirm the potential of H₂L(A3) as a robust, regenerable, and selectively engineered sorbent for sustainable heavy metal remediation.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Hydrazone-Based Sorbent for High-Performance Removal of Cadmium and Copper from Aqueous Media

  • 期刊论文

  • 发表日期：

    2026年2月19日

查看全文
  • Sabreen M. El-Gamasy,
  • Entsar H. Taha,
  • Ahmed M. Masoud,
  • Adel A. El-Zahhar,
  • Majed M. Alghamdi,
  • Mohamed H. Taha,
  • Amal E. Mubark

摘要

The persistent contamination of water by cadmium (Cd2⁺) and copper (Cu2⁺) poses acute risks to human health and ecosystems, and continues to challenge conventional treatment technologies. In this study, a rationally designed hydrazone-based ligand, H₂L(A3), enriched with nitrogen and oxygen donor sites, was synthesized and evaluated as a selective sorbent for Cd(II) and Cu(II) removal from aqueous media. The material was rigorously characterized using elemental analysis, mass spectrometry (MS), Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), X-ray diffraction (XRD), Brunauer–Emmett–Teller/ Barrett–Joyner–Halenda (BET/ BJH) surface area analysis, dynamic light scattering (DLS), zeta potential (ζ), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM–EDX), and thermogravimetric analysis (TGA). These techniques confirmed the ligand’s molecular identity, heteroatom-rich surface, mesoporous texture (2–4 nm), moderate surface area (~ 54 m2 g⁻1), submicron dispersion, and thermal stability. Batch adsorption studies explored the effects of pH, dose, contact time, temperature, and initial concentration, with data interpreted using nonlinear kinetic (pseudo-first-order, pseudo-second-order, intraparticle diffusion), isotherm (Langmuir, Freundlich, Temkin, D-R, Sips), and thermodynamic (van’t Hoff) models. H₂L(A3) exhibited high monolayer adsorption capacities (qₘₐₓ) of 108.3 mg g⁻1 for Cd(II) and 83.4 mg g⁻1 for Cu(II), reflecting strong affinity and preferential interaction with Cd(II). Adsorption was spontaneous and exothermic (ΔG°, ΔH° < 0; ΔS° < 0), indicating an electrostatically assisted chemisorption process dominated by inner-sphere coordination on N, O donor sites. Regeneration with 1.0 M nitric acid (HNO₃) achieved 90–94% desorption, with ≥ 75% efficiency retained after three cycles. Importantly, in real wastewater matrices containing competing ions, H₂L(A3) maintained selective removal performance, achieving 49.2% Cd(II) and 23.8% Cu(II) removal. These results confirm the potential of H₂L(A3) as a robust, regenerable, and selectively engineered sorbent for sustainable heavy metal remediation.