A promising natural material for pollutants removal

Area of Science:

• Environmental Science
• Materials Science
• Chemistry

Background:

• Natural resources offer eco-friendly, cost-effective solutions for pollutant removal.
• Persistent dyes like Reactive Black 5 (RB5) and Methylene Blue (MB) pose significant wastewater challenges.
• Volcanic tuff, particularly Romanian deposits rich in clinoptilolite, is explored for its remediation potential.

Purpose of the Study:

• To evaluate the efficacy of Romanian volcanic tuff in removing RB5 and MB via photo-Fenton-like oxidation.
• To characterize the structural, mineralogical, and textural properties of natural and modified volcanic tuff.
• To investigate the potential of volcanic tuff as a sustainable material for wastewater treatment.

Main Methods:

• Photo-Fenton-like oxidation process using modified volcanic tuff.
• Material characterization using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectroscopy (FT-IR), N2 adsorption-desorption, and Surface-Enhanced Raman Scattering (SERS).
• Dye removal efficiency and degradation kinetics (k) were quantified.

Main Results:

• Romanian volcanic tuff, with up to 85% clinoptilolite, demonstrated high effectiveness in removing RB5 and MB (>90%) from real wastewater.
• Degradation rate constants (k) ranged from 0.0242-0.0309 min⁻¹.
• The material maintained significant RB5 decolorization (>60%) even after five treatment cycles.
• SERS provided novel structural insights into the volcanic tuff.

Conclusions:

• Romanian volcanic tuff is a highly effective and reusable adsorbent for removing persistent dyes from wastewater.
• The material's properties, including its clinoptilolite content, contribute to its excellent performance in photo-Fenton-like oxidation.
• Exploiting Romanian volcanic tuff presents a promising green solution for sustainable wastewater treatment.