Pentachlorophenol removal from aqueous matrices by sorption with almond shell residues
B N Estevinho1, N Ratola, A Alves
1LEPAE-Departamento de Engenharia Química, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
Journal of Hazardous Materials
|May 23, 2006
Summary
Almond shells effectively remove pentachlorophenol (PCP) from water, offering a low-cost alternative to activated carbon. This agricultural waste demonstrates strong adsorption capacity with minimal desorption, making it a promising sustainable solution for water remediation.
Area of Science:
- Environmental Science
- Materials Science
- Chemical Engineering
Background:
- Activated carbon is the standard for pentachlorophenol (PCP) removal, but high costs and regeneration issues necessitate alternatives.
- Agricultural by-products like almond shells present an economical and sustainable option for water treatment.
Purpose of the Study:
- To evaluate the efficacy of untreated almond shells as a sorbent for removing pentachlorophenol (PCP) from contaminated water.
- To characterize the physical and chemical properties of almond shells relevant to their sorption capabilities.
Main Methods:
- Batch sorption experiments were conducted to assess PCP removal by almond shells.
- PCP analysis utilized solid-phase microextraction (SPME) coupled with gas chromatography-electron capture detection (GC-ECD).
- Mercury porosimetry and Fourier transform infrared spectroscopy (FTIR) were employed for sorbent characterization.
Main Results:
- Almond shells exhibited a macroporous structure with a surface area of 12.9 ± 2.8 m²/g.
- A removal efficiency of 93 ± 14% for PCP was achieved within 24 hours under tested conditions.
- Adsorption data best fit the Freundlich isotherm model, indicating strong sorption with low desorption (average 7%).
Conclusions:
- Untreated almond shells are a highly effective and low-cost sorbent for pentachlorophenol (PCP) removal from water.
- Almond shells represent a viable, eco-friendly alternative to conventional sorbents in water remediation efforts.
- The strong adsorption capacity and minimal desorption suggest excellent performance in practical applications.
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