New Low-Cost Ceramic Microfiltration Membranes for Bacteria Removal

Area of Science:

• Materials Science
• Environmental Engineering
• Water Treatment Technologies

Background:

• Safe water access in low-income regions is challenged by financial constraints and natural disasters.
• Point-of-use water treatment technologies require cost-efficiency and local material utilization.

Purpose of the Study:

• To develop and characterize novel ceramic microfiltration membranes from readily available local raw materials (kaolin, bentonite, limestone).
• To evaluate the efficiency of these membranes in rejecting common waterborne bacteria, specifically *Escherichia coli* and *Staphylococcus aureus*.

Main Methods:

• Membrane characterization using Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Fourier-Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Mercury Intrusion Porosimetry.
• Assessment of physical properties including flexural strength and water uptake.
• Evaluation of bacterial rejection efficiency and water permeability.

Main Results:

• The addition of limestone influenced pore size, porosity, and permeability, but negatively impacted rejection rates.
• A specific composition (83% kaolin, 10% bentonite, 7% limestone) demonstrated an optimal balance between permeability and rejection.
• This optimized membrane achieved a water permeability of 566 L·h⁻¹·m⁻²·bar⁻¹ and 100% rejection of *Escherichia coli* and *Staphylococcus aureus*.

Conclusions:

• Novel, low-cost ceramic microfiltration membranes were successfully fabricated using local materials.
• The developed membranes show significant potential for effective point-of-use water treatment in resource-limited settings.
• These membranes offer a promising solution for improving safe water provision, particularly in household applications and during emergencies.