Exploring the Potential of Geopolymers in Sustainable Construction
Geopolymers represent a groundbreaking category of materials that provides an environmentally friendly alternative to traditional Portland cement. These inorganic polymers are synthesized by activating aluminosilicate precursors with alkaline or acidic solutions, most notably sodium, potassium, or calcium hydroxide and phosphoric acid. Despite the potential benefits, the use of phosphoric acid in geopolymer synthesis remains underexplored. The selection of suitable aluminosilicate precursors, such as natural clays, and the fine-tuning of synthesis parameters significantly affect the mechanical properties of the resulting geopolymers. This study delves into the synthesis of geopolymers utilizing Moroccan clay (MC) as an aluminosilicate precursor, with phosphoric acid (H₃PO₄) serving as the activating agent.
During the investigation, various parameters were analyzed, including the Al/Si molar ratio, the concentration of phosphoric acid, and the curing temperature, all of which were meticulously optimized using Response Surface Methodology (RSM) to assess their impact on the compressive strength of the geopolymers produced. The findings revealed that a high concentration of H₃PO₄ (10 mol/L) yielded a compressive strength of 0.5 MPa after 14 days and 1.5 MPa after 28 days. However, it was observed that concentrations ranging between 5.5 and 7.0 mol/L resulted in superior compressive strength, achieving up to 36 MPa. Furthermore, lowering the curing temperature to 56.8°C was found to enhance mechanical resistance significantly. The optimal Al/Si molar ratios for achieving high compressive strength were identified to be between 1.2 and 1.4. The utilization of locally sourced clays in the synthesis of geopolymers aligns with global objectives aimed at developing sustainable construction materials, thereby promoting environmentally responsible practices in the building industry.
As reported by link.springer.com.
