Refractory Bricks Characterization Manufactured from Geopolymers Based on Volcanic Ash

Purpose: The purpose of this study is to analyze the mechanical and physical properties of refractory bricks manufactured by geopolymerization from volcanic ash to obtain a product with better properties and contribute to the sustainable use of natural resources. Method: For the refractory bricks preparation, volcanic ash was used with 12 M sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) as activators, with a liquid/solid ratio of 0.2. 02 brick prototypes were manufactured, a cylindrical specimen prototype for the study of resistance to compression and absorption; and a prototype of a rectangular prism to analyze thermal conductivity. The refractory bricks were subjected to a calcination process at 600°C and 800°C to analyze their properties. Results and Discussion: The compressive strength of the cylindrical specimens at a temperature of 600°C reached an average of 5.51 MPa, while those manufactured at a temperature of 800°C recorded an average of 6.60 MPa, these results representing double compared to the resistance at the average compression of 2.80 MPa of commercial refractory bricks. The average density values of the specimens manufactured at 600°C and 800°C were similar and equivalent to 1.58 g/cm3 and higher compared to the average density of 0.95 g/cm3 of commercial bricks. Furthermore, the average thermal conductivity obtained in the manufactured refractory bricks was 0.008 W/mK, a value that is interesting due to its greater insulating properties compared to that of commercial refractory bricks that have an average value of 0.39 W/mK of thermal conductivity. Indeed, properties with optimal results were achieved in the manufacture of refractory bricks made from geopolymers. Research Implications: The use of volcanic ash for the production of geopolymer-based bricks allows obtaining more environmentally friendly products with good performance in terms of properties comparable to those of known commercial refractory bricks. Originality/Value: This study contributes to the field of the construction industry by providing an alternative to the processing of refractory bricks by geopolymerization from volcanic ash, offering important knowledge for industry and academia.