Growing bio-tiles using microbially induced calcium carbonate precipitation

Area of Science:

• Materials Science
• Biotechnology
• Sustainable Construction

Background:

• Conventional ceramic tile production requires high temperatures (>1000°C), contributing to significant global carbon emissions.
• There is a need for sustainable building materials that reduce environmental impact and energy consumption.

Purpose of the Study:

• To investigate the growth of bio-tiles using microbially induced calcium carbonate precipitation (MICP) as a sustainable alternative to ceramic tiles.
• To optimize parameters for producing bio-tiles with mechanical properties comparable to conventional tiles.

Main Methods:

• Utilized the ureolytic activity of Sporosarcina pasteurii for MICP.
• Employed a novel submersion method with custom molds for bio-tile growth.
• Optimized key parameters including ureolytic activity, cementation solution concentration, particle size distribution, solution volume, and magnesium supplementation.

Main Results:

• Achieved bio-tile dimensions of 100 × 100 × 10 mm.
• Produced bio-tiles with a breaking strength of 637 N ± 60 N and a modulus of rupture of 13.0 N/mm² ± 2.3 N, exceeding conventional standards.
• Identified an optimal CaCO₃ precipitation rate constant (0.11-0.18 day⁻¹) for bio-tile production.

Conclusions:

• The optimized MICP process yields bio-tiles that meet or exceed the strength requirements of conventional ceramic tiles.
• The developed bio-tile manufacturing technique is scalable, easy to operate, and environmentally friendly, operating at room temperature.
• This study presents a viable, low-carbon footprint alternative for tile production.