Conversion of chromium-containing solid wastes into value-added products through a plasma-assisted aluminothermic...

Area of Science:

• Environmental Science
• Materials Science
• Chemical Engineering

Background:

• Industrial chromium waste poses significant environmental and health risks due to toxic hexavalent chromium (Cr⁶⁺).
• Current treatment methods for chromium waste are often inefficient, time-consuming, or generate secondary pollutants.
• Contaminated soil and groundwater from improper waste disposal lead to severe ecological and human health issues.

Purpose of the Study:

• To develop an efficient and rapid method for detoxifying chromium-containing solid wastes.
• To convert hazardous hexavalent chromium (Cr⁶⁺) into stable, non-toxic forms.
• To recover valuable metals from industrial chromium waste.

Main Methods:

• A plasma-assisted aluminothermic process was employed, utilizing transferred arc plasma treatment.
• Industrial chromium waste was mixed with aluminum powder and treated in a controlled air atmosphere.
• Chemical analysis and chromium leachability studies were conducted on pre- and post-treatment materials.

Main Results:

• The plasma treatment successfully converted toxic chromium waste into non-toxic products.
• Chromium and iron were recovered as a separable metallic mixture and oxide slag.
• Leachability studies confirmed the non-toxic nature of the treated materials.
• The process demonstrated complete metal recovery from the waste.

Conclusions:

• Plasma-assisted aluminothermic treatment is a rapid and effective method for detoxifying hazardous chromium waste.
• This process offers a sustainable solution for managing industrial chromium waste, minimizing environmental impact.
• The recovery of metals presents an opportunity for resource valorization from waste streams.