Volcanic Ash as a Sustainable Binder Material: An Extensive Review

Area of Science:

• Materials Science
• Civil Engineering
• Sustainable Construction

Background:

• Growing urban populations increase demand for cement, leading to significant environmental impact.
• Portland cement production is energy-intensive and contributes to greenhouse gas emissions.
• There is an urgent need for sustainable alternatives in the construction industry.

Purpose of the Study:

• To explore the potential of alkali-activated volcanic ash (VA) as a sustainable binder alternative to Portland cement.
• To review global research on the influence of volcanic ash composition and alkali-activation parameters on material properties.
• To assess the mechanical performance and durability of alkali-activated VA-based materials for construction applications.

Main Methods:

• Review of existing literature on alkali-activated volcanic ash.
• Analysis of the role of volcanic ash chemical composition and mineralogy in alkali-activation reactivity.
• Investigation of synthesis factors: alkaline activator concentration, solution-to-binder ratio, and curing conditions.

Main Results:

• Volcanic ash's chemical composition and amorphous structure are key to its reactivity in alkali activation.
• Synthesis factors significantly influence the densification, porosity, and mechanical properties of the resulting materials.
• Alkali-activated VA materials demonstrate good mechanical performance and low porosity, suitable for building applications.

Conclusions:

• Alkali-activated volcanic ash is a viable, sustainable alternative binder for cement production.
• Optimizing synthesis parameters is crucial for tailoring the properties of VA-based materials.
• Further research can unlock the full potential of volcanic ash in eco-friendly construction.