Tecnologia em Metalurgia, Materiais e Mineração
https://tecnologiammm.com.br/doi/10.4322/2176-1523.20191474
Tecnologia em Metalurgia, Materiais e Mineração
Artigo Original

INFLUÊNCIA DA CONCENTRAÇÃO DE NaOH NA SÍNTESE DE GEOPOLÍMERO COM REAPROVEITAMENTO DE RESÍDUO INDUSTRIAL

INFLUENCE OF NaOH CONCENTRATION IN THE SYNTHESIS OF GEOPOLYMER WITH REUSE OF INDUSTRIAL WASTE

Woshington da Silva Brito, André Luis Mileo Ferraioli Silva, Kristoff Svensson, Herbert Pöllmann, Rozineide Aparecida Antunes Boca Santa, Humberto Gracher Riella, José Antônio da Silva Souza

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Resumo

A concentração molar do ativador alcalino é um parâmetro importante na síntese de geopolímero com reaproveitamento de cinza volante e metacaulim. O trabalho de pesquisa tem como objetivo avaliar o desempenho mecânico dos geopolímeros com razão de Davidovits (SiO2 /Al2 O3 ) de 2,65, sintetizados com diferentes concentrações molares de NaOH (5, 15, 30 e 40 Molar) no ativador. A reação de geopolimerização foi conduzida a temperatura ambiente de 28°C e como ativador utilizou-se hidróxido de sódio (NaOH) e silicato de sódio (Na2 SiO3 ) alcalino 10 Molar. Os geopolímeros sintetizados com 5 e 15 molar de NaOH apresentaram alta resistência a compressão. Apresentando 40,8 MPa com 28 dias de cura para o geopolímero sintetizado com 15 molar. Os geopolímeros sintetizados com 30 e 40 molar de NaOH apresentaram baixa resistência a compressão.

Palavras-chave

Geopolímero; NaOH; Cinza leve; Metacaulim.

Abstract

The molar concentration of the alkaline activator is an important parameter in the synthesis of geopolymer with reuse of fly ash waste and metakaolin. The objective of this work was to evaluate the mechanical performance of the Davidovits (SiO2 /Al2 O3 ) geopolymers of 2,65 synthesized with different concentrations of NaOH (5, 15, 30, 40 Molar) in the activator. The geopolymerization reaction was conducted in ambient temperature of 28°C and 15 Molar sodium hydroxide (NaOH) and 10 Molar sodium silicate (Na2 SiO3 ), were used as the activator. The geopolymers synthesized with 5 and 15 molar NaOH showed high compressive strength. Featuring 40.8 MPa with 28 days cure for the 15 molar synthesized geopolymer. The geopolymers synthesized with 30 and 40 molar NaOH showed low compressive strength.

Keywords

Geopolymers; NaOH; Fly ash; Metakaolin.

Referências

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