Silver removal from aqueous solution by biochar produced from biosolids via microwave pyrolysis

Area of Science:

• Environmental Science
• Materials Science
• Water Treatment

Background:

• Increasing water contamination by silver due to its antimicrobial applications.
• Adsorption presents a cost-effective strategy for removing silver from aqueous solutions.

Purpose of the Study:

• To investigate the use of biochar derived from biosolids for silver removal from water.
• To elucidate the adsorption kinetics, isotherms, and thermodynamics of silver removal by biochar.

Main Methods:

• Microwave-assisted pyrolysis of biosolids to produce biochar.
• Batch adsorption experiments to study silver removal.
• Analysis using X-ray diffraction, Langmuir isotherm, and thermodynamic studies.

Main Results:

• Silver removal by biochar involves both reduction and physical adsorption mechanisms.
• The Langmuir model indicated predominantly surface-based silver removal.
• Thermodynamic analysis confirmed silver removal as an exothermic process.
• The resulting Ag-biochar nanocomposite showed potential for methylene blue adsorption and photodegradation.

Conclusions:

• Biochar produced from biosolids is a viable and sustainable material for silver removal from water.
• This approach offers a dual benefit of mitigating water pollution and enabling biosolids management and reuse.