Application of magnetically modified sewage sludge ash (SSA) in ionic dye adsorption

Area of Science:

• Environmental Chemistry
• Materials Science
• Waste Management

Background:

• Incineration of sewage sludge produces ash, posing a secondary waste disposal challenge.
• Developing effective adsorbents from waste materials is crucial for sustainable environmental management.
• Ionic dyes in wastewater require efficient removal methods to prevent pollution.

Purpose of the Study:

• To investigate the potential of ferrite-coated sewage sludge ash (SSA) as an adsorbent for ionic dyes.
• To characterize the adsorption performance of modified SSA for methylene blue (MB) and Procion Red MX-5B (PR).
• To determine optimal adsorption conditions and evaluate the adsorption kinetics and capacity.

Main Methods:

• Sewage sludge ash (SSA) was modified using a ferrite process.
• The modified SSA was used as an adsorbent for methylene blue (MB) and Procion Red MX-5B (PR).
• Adsorption experiments were conducted to determine optimal pH, adsorption capacity (Langmuir isotherm), and kinetics (pseudo-second-order model).

Main Results:

• Ferrite-coated SSA exhibited electrostatic attraction towards MB and PR.
• Adsorbent FA10 showed a maximum adsorption capacity of 22.03 mg/g for MB at pH 9.0.
• Adsorbent FA2.5 achieved a maximum adsorption capacity of 28.82 mg/g for PR at pH 3.0.
• Adsorption kinetics for both dyes followed the pseudo-second-order model.

Conclusions:

• Ferrite-modified SSA is a promising adsorbent for removing ionic dyes from wastewater.
• The adsorbent demonstrates efficient dye removal with varying optimal conditions for different dyes.
• This approach offers a sustainable method for valorizing sewage sludge ash in environmental remediation.