Compressive Strength and Microstructural Characterization of Fly Ash and Palm Shell Activated Carbon Based Geopolymer Mortar

This study aims to develop mortar as an environmentally friendly building material based on geopolymer by utilizing fly ash as the main binder and activated carbon from palm shells as an additive. This study focuses on the analysis of the microstructure of geopolymer mortar, including the effect of the proportion of fly ash and activated carbon on mechanical properties and pore structure. Testing was carried out using the EDX, SEM, FTIR and compressive strength test methods to evaluate the relationship between material composition, internal structure, and mechanical performance. The results showed that the addition of activated carbon from palm shells to geopolymer mortar increased the compressive strength with test results of 26 MPa for 14 days. EDX testing resulted in the dominance of Oxides which play a role in the formation of the geopolymer structure, (Oxygen 49.18%, Sodium 15.10%, Aluminum 4.16%, Calcium 15.90%, Silicon 8.50%, Carbon 4.30%, Magnesium 2.10%). Based on SEM testing there are pores that will affect the compressive strength test. FTIR testing shows an aluminosilicate structure in geopolymer mortar and the contribution of activated carbon in producing certain characteristics. In addition, the application of this waste-based material supports sustainable development and carbon emission reduction in the construction sector.