Removal of Copper (II) from Aqueous Solutions Using Silica Xerogel as Sorbent: Adsorption Properties and Mechanism

Removal of Copper (II) from Aqueous Solutions Using Silica Xerogel as Sorbent: Adsorption Properties and Mechanism

Článek WoS

The contamination of water resources with heavy metals creates problems for using it as a source of drinking water. Adsorption is one of the most promising methods for heavy metal ion removal from natural and wastewater. The process of removing copper (II) from aqueous solutions using SiO2 xerogel as an adsorbent has been studied. The xerogel was thoroughly characterized by transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and argon adsorption-desorption isotherms, revealing an amorphous structure with a high surface area (similar to 347 m(2)/g) and uniform mesoporosity (2-14 nm pore size). The surface chemistry, dominated by silanol groups, was confirmed by XPS analysis. The adsorption process is influenced by electrostatic interactions between the positively charged Cu(II) ions and the negatively charged surface groups, with the optimal performance near neutral pH. Batch adsorption experiments demonstrated that the silica xerogel effectively removes Cu(II) ions from aqueous solutions, with removal efficiency exceeding 99% at pH values above 4.0. The maximum adsorption capacity of copper (II) ions on SiO2 xerogel is 67.5 mg/L.

The contamination of water resources with heavy metals creates problems for using it as a source of drinking water. Adsorption is one of the most promising methods for heavy metal ion removal from natural and wastewater. The process of removing copper (II) from aqueous solutions using SiO2 xerogel as an adsorbent has been studied. The xerogel was thoroughly characterized by transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and argon adsorption-desorption isotherms, revealing an amorphous structure with a high surface area (similar to 347 m(2)/g) and uniform mesoporosity (2-14 nm pore size). The surface chemistry, dominated by silanol groups, was confirmed by XPS analysis. The adsorption process is influenced by electrostatic interactions between the positively charged Cu(II) ions and the negatively charged surface groups, with the optimal performance near neutral pH. Batch adsorption experiments demonstrated that the silica xerogel effectively removes Cu(II) ions from aqueous solutions, with removal efficiency exceeding 99% at pH values above 4.0. The maximum adsorption capacity of copper (II) ions on SiO2 xerogel is 67.5 mg/L.

xerogel, silica, adsorption, capacity, copper (II), removal

xerogel, silica, adsorption, capacity, copper (II), removal

SHANAZ, A.; ABDULGALIM, I.; SCHUBERT, R.; ILYA, P.; VALERY, T.

2026

01.09.2025

Mdpi

Colloids and Interfaces

9

58

Švýcarská konfederace

1

17

17

https://www.mdpi.com/2504-5377/9/5/58