Chemically treated carbon black waste and its potential applications

Area of Science:

• Materials Science
• Environmental Science
• Chemical Engineering

Background:

• Carbon black waste from oil refining poses environmental and health risks due to heavy metal contamination.
• Developing sustainable methods for waste valorization is crucial for circular economy principles.

Purpose of the Study:

• To detoxify hazardous carbon black waste and evaluate its potential as an adsorbent material.
• To investigate the removal efficiency of heavy metals (nickel and vanadium) from carbon black waste.
• To assess the cytotoxicity and adsorption capacity of the treated carbon black waste.

Main Methods:

• Chemical leaching using nitric acid to remove heavy metals (nickel and vanadium).
• Cytotoxicity assessment using human lung cells (MRC-5) to evaluate leachate toxicity.
• Dye adsorption experiments to determine the adsorption capacity of the treated material.
• Measurement of specific surface area and electrical conductivity.

Main Results:

• Nitric acid leaching effectively removed up to 95% nickel and 98% vanadium.
• Leachate from treated carbon black waste showed no significant toxicity to human lung cells.
• The treated carbon black waste exhibited a high dye adsorption capacity of ~361.2 mg/g.
• The material possesses a high specific surface area (~559 m²/g) and electrical conductivity (~10 S/cm).

Conclusions:

• Detoxified carbon black waste is a promising, non-toxic adsorbent material for dye removal.
• The treated waste is a valuable source of sustainable material with potential applications in adsorption and as a conductive material.