Use of rice husk ash to produce alternative sodium silicate for geopolymerization reactions

AUTOR(ES)

Lima, J. S.; Apolonio, P. H.; Marinho, E. P.; Vasconcelos, E. A.; Nóbrega, A. C. V.; Freitas, J. C. O.

FONTE

Cerâmica

DATA DE PUBLICAÇÃO

2021-03

RESUMO

Abstract This study investigated the feasibility of synthesizing sodium silicate from rice husk ash (RHA) and its application to produce geopolymers. Samples were prepared at different SiO2/Al2O3 molar ratios (3.0, 3.5, and 4.0) for both sodium silicates (commercial and from RHA). They were underwater cured at 60 ºC for 1 h and then at room temperature (25 ºC in the air) until the time of the tests (7 and 28 days). The results showed that the compressive strength significantly increased along with the SiO2/Al2O3 ratio for both silicates. Geopolymers produced with sodium silicate from RHA showed higher compressive strengths for most studied samples. The highest compressive strength (6.33±0.23 MPa) was obtained for samples with SiO2/Al2O3 ratio of 4.0 at 7 days, representing a 40% increase in average values compared to commercial sodium silicate under the same conditions. XRD data and FTIR spectrum confirmed that it was possible to synthesize a geopolymer with sodium silicate using RHA.

Documentos Relacionados

• Conversion of rice hull ash into soluble sodium silicate
• Properties of silica from rice husk and rice husk ash and their utilization for zeolite y synthesis
• Study on properties of rice husk ash and its use as cement replacement material
• Production of silica gel from residual rice husk ash
• Rice husk ash as filler in tread compounds to improve rolling resistance