Recyclable structured toxic industrial nickel-containing sludge for efficient anionic contaminant adsorption

Area of Science:

• Materials Science
• Environmental Engineering
• Waste Management

Background:

• Simultaneous treatment of toxic industrial sludge and anionic contaminants is a global challenge.
• Recycling toxic waste like nickel-containing sludge (NCS) into valuable materials is crucial for sustainability.

Purpose of the Study:

• To develop a low-cost, high-performance adsorbent from NCS for simultaneous waste treatment and wastewater remediation.
• To investigate the structural properties and adsorption capabilities of the novel sludge-based adsorbent.

Main Methods:

• A waste-control-waste strategy was employed to synthesize Ni-Al layered double oxides/calcined NCS (Ni-Al LDOs/CNCS).
• Hydrothermal treatment at 180 °C for 24 h was optimized for in situ assembly of LDH nanosheets.
• Adsorption capacities for various anions (F-, SO42-, NO3-, Cl-, H2PO4-) were evaluated.

Main Results:

• The Ni-Al LDOs/CNCS adsorbent exhibited a hierarchical porous structure with a larger specific surface area (216.96 m²/g) compared to raw NCS.
• High adsorption capacities were achieved for F-, SO42-, NO3-, Cl-, and H2PO4- anions.
• The adsorbent demonstrated good reusability over 6 adsorption/desorption cycles.

Conclusions:

• The developed Ni-Al LDOs/CNCS is a promising material for efficient wastewater treatment and toxic sludge valorization.
• This approach offers a sustainable pathway for transforming industrial waste into high-value adsorbents.
• The study paves the way for designing other sludge-derived materials for environmental applications.