Process intensification through waste fly ash conversion and application as ceramic membranes: A review

Area of Science:

• Materials Science
• Environmental Engineering
• Chemical Engineering

Background:

• Fly ash, a byproduct of thermal power plants, poses environmental risks due to improper disposal.
• Research is exploring the valorization of fly ash into functional materials, specifically membranes.
• Fly ash-based membranes offer a sustainable solution for waste utilization and pollution control.

Purpose of the Study:

• To provide a comprehensive overview of fly ash-based membrane fabrication methods.
• To discuss critical parameters influencing membrane performance.
• To highlight the application of these membranes in wastewater treatment and composite membrane fabrication.

Main Methods:

• Review of various fabrication techniques for fly ash-based membranes.
• Discussion of coating methods for creating composite membranes.
• Analysis of extrusion as a scalable method for bulk production.
• Examination of separation principles (size exclusion and charge-based).

Main Results:

• Fly ash-based membranes are effective for treating diverse wastewater streams.
• The extrusion method is suitable for industrial-scale membrane production.
• Composite membranes can be fabricated using fly ash supports.
• Membranes operate via size exclusion or charge-based separation principles.

Conclusions:

• Fly ash-based membranes present a cost-effective and environmentally beneficial approach to wastewater treatment.
• Further research and development are needed to optimize fabrication and application.
• Caution is advised regarding use in acidic solutions due to potential heavy metal leaching.