Exploring Tanzanian Clay Minerals as Promising Candidates for Geopolymer Cement: A Sustainable Approach to Climate-Friendly Cement

Abstract

The quest for sustainable construction materials has sparked interest in geopolymers as eco-friendly alternatives to traditional Portland cement. In response to this endeavour, this study explored Tanzanian clay minerals collected from different regions to assess their potential as candidate materials for geopolymer cement. The XRF results revealed varying elemental compositions that are crucial for geopolymer production. Essential components like SiO2 and Al2O3 were found, with some regions showing balanced ratios suitable for geopolymer cement. Minor Fe2O3 content was also detected, which could enhance material strength by forming iron silicate binders. Limited CaO content was noted, which can be beneficial in influencing geopolymer properties. However, high CaO levels in a few regions of the Eastern zone may be less suitable for geopolymer cement production. Most samples showed minimal Loss of Ignition (LOI), indicating their potential to enhance the workability of geopolymers. The study identified specific regions with clays suitable for various high-technology geopolymer resins, low-CO2 geopolymer cement, and specialized applications, though beneficiation might sometimes be required. The XRD results of clay samples revealed varying mineral compositions, with quartz being the dominant mineral in several samples, indicating high silica content. These mineralogical findings align with the XRF results, reinforcing the presence of essential elements for geopolymer cement development. The SEM-EDS results further verified the elemental composition of select samples. Additionally, TGA results provided insights into the thermal stability of the clay samples, confirming their suitability for geopolymer cement production. These results demonstrated that Tanzanian clay minerals are well-suited for producing eco-friendly cement. By leveraging these readily available local clay resources and unlocking their potential for sustainable construction materials, this research significantly advances the worldwide endeavour to mitigate the environmental footprint of the construction sector while advocating for eco-conscious alternatives to conventional Portland cement.