Fabrication of Metakaolin/Ignimbrite Geopolymer from the Añashuayco Quarry in Arequipa

The construction industry is crucial for social and economic development, but it faces sustainability challenges. About 40% of global industrial waste comes from construction, and cement contributes approximately 8% of global CO 2 emissions. This study aims to develop more sustainable materials by reusing waste and creating a new environmentally friendly binder, geopolymer, from ignimbrite (IG) from Arequipa, Peru, and metakaolin. Metakaolin from China (MKCh) and locally calcined metakaolin (MK650 and MK750) were used. The materials were characterized by XRD, FTIR, and SEM-EDS. Cylindrical geopolymers were produced with MK and IG ratios of 100/0 and 60/40, using a 9 mol/L NaOH activator solution. Curing was performed at 25 °C for 24 h, followed by 72 h at 50 °C. The results showed that the addition of IG increased the compressive strength, with the best performance observed in the MK-IG-60-40 material, with 52.72 ± 1.02 MPa. Thus, the addition of ignimbrite demonstrated to improve the strength of the geopolymers.