Per: RAYANNE OLIVEIRA LEãO SANTANA (UNIVERSIDADE FEDERAL DO PARÁ), Paulo Anderson Aranha Ferreira (UNIVERSIDADE FEDERAL DO PARÁ), Giovana Zagalo de França (UNIVERSIDADE FEDERAL DO PARÁ), vitor leão Santana (UNIVERSIDADE FEDERAL DO PARÁ), Alisson Clay Rios da Silva (UNIVERSIDADE FEDERAL DO PARÁ), Verônica Scarpini Candido (UNIVERSIDADE FEDERAL DO PARÁ)
Abstract:
Geopolymers are formed by a three-dimensional matrix of aluminosilicates, have the potential to replace traditional Portland cement. Hard kaolin, a by-product of the paper industry, is rich in kaolinite and can be transformed into metakaolin, a reactive precursor in geopolymerizationThis study analyzes the influence of calcination temperature on hard kaolin waste in the production of geopolymer cement.. The research utilized metakaolin derived from hard kaolin and blast furnace slag, subjecting them to calcination at 550°C, 650°C, and 750°C. The compressive strength results were 20.9 MPa, 31.4 MPa, and 39.8 MPa, respectively, showing that increasing the temperature improves the strength of the geopolymers. Additional tests revealed that water absorption and porosity decrease while density increases at higher temperatures, indicating a denser and more cohesive structure at 750°C. Microscopic analysis confirmed higher geopolymerization efficiency at 750°C, evidenced by the absence of cracks, bubbles, and unreacted material, resulting in a more homogeneous and dense matrix. It is concluded that calcination at 750°C is the most effective in optimizing the physical and mechanical properties of geopolymers, highlighting their potential as an efficient and durable substitute for conventional cement in civil construction.