Waste-Derived Geopolymers for Artificial Coral Development by 3D Printing

Abstract

Coral reefs are vital to marine ecosystems, providing habitat and protection for marine life and serving as natural barriers against coastal erosion. However, coral degradation due to climate change, coastal development, and marine exploration require alternatives like artificial corals. This study explores the use of geopolymers based on industrial waste, specifically biomass fly ash and red mud, for creating artificial corals. Geopolymers offer an eco-friendly solution by repurposing waste materials and providing resistance to environmental stressors like saline water. This research investigates the mineralogical and mechanical properties of geopolymers formed using 3D printing and casting. The 3D-printed samples exhibited compressive strengths ranging from 4 to 10 MPa, sufficient to withstand marine environmental stresses, although lower than the 20 to 30 MPa observed in cast samples. The mineralogical analysis showed the presence of compatible phases including hematite and calcium carbonate, which enhance environmental compatibility. The study highlights the potential of waste-based geopolymers as sustainable materials for artificial corals, emphasizing the benefits of using 3D printing to generate complex geometries and endow marine integration.