Síntese e caracterização de argamassa geopolimérica a base de metacaulinita e cinza de fundo

Abstract

The increased use of cementitious materials and the negative consequences that this causes on the environment, makes great efforts in the development of research that seeks new materials, less polluting, with technical compactness and low cost. The present research presents the development and characterization of geopolymeric mortars based on metacaulinite evaluating the substitution in 25%, 50% and 100% of the small aggregate by background ash from local potteries and that is an unavoidable byproduct and without sustainable destination. In order to obtain purer precursors, it was chosen to produce metacaulinite manually, the collected kaolinite clay was calcined at a temperature of 750 ° C for 4 hours, using active silica, deionized water and sodium hydroxide as the alkaline activator. Fluorescence and xray diffraction techniques were used for the chemical and mineralogical characterization of kaolinite and metacaulinite and through the simple compression strength test the mechanical performance of the specimens was obtained. The mechanical results reached 45 MPA in 100% substitution and also indicated that proportions less than 50% are not feasible because they reduce the resistance. Regarding the physical properties of the mixture, the results show that the geopolymer mortars produced in the present work resemble the geopolymer mortars studied in other researches. In view of this, it is concluded that the incorporation of bottom ash for the production of geopolymeric mortars makes the material technically compatible with conventional cements materials.