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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Characterization of solids originating from the Fenton's process
Cláudia Telles Benatti1, Antônio Carlos Saraiva da Costa, Célia Regina Granhen Tavares
1Departamento de Engenharia Química, Universidade Estadual de Maringá, Av. Colombo, 5790 Bloco D90, 87020-900 Maringá, PR, Brazil.
Journal of Hazardous Materials
|September 24, 2008
Summary
Fenton's process effectively removes heavy metals but creates hazardous solid residues. These residues, rich in amorphous material, pose significant environmental risks requiring careful disposal management.
Area of Science:
- Environmental Chemistry
- Waste Management
Background:
- Fenton's process is effective for oxidizing organic pollutants and removing heavy metals.
- A significant by-product of Fenton's process is a solid residue laden with metals.
Purpose of the Study:
- To characterize solid residues from Fenton's oxidation of academic laboratory mixed waste chemicals.
- To evaluate the effect of wastewater characteristics on residue composition and metal mobility.
- To assess the environmental risks associated with these hazardous residues.
Main Methods:
- Application of Fenton's oxidation to different wastewater samples.
- Leaching tests to evaluate residue properties.
- Chemical speciation and sequential dissolution procedures for metal mobility assessment.
- Classification according to Brazilian waste regulations.
Main Results:
- Residues were classified as hazardous under Brazilian waste regulations.
- Metals in residues are predominantly associated with amorphous material (>80%).
- Reactive fractions (exchangeable, amorphous iron oxide) retain the majority of metals.
Conclusions:
- Fenton's residues present a high potential for environmental contamination.
- Effective administration and controlled disposal are crucial for managing these hazardous by-products.
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