The effect of micro-SiO2 and micro-Al2O3 additive on the strength properties of ceramic powder-based geopolymer pastes


KAYA M.

JOURNAL OF MATERIAL CYCLES AND WASTE MANAGEMENT, 2021 (Journal Indexed in SCI) identifier

  • Publication Type: Article / Article
  • Publication Date: 2021
  • Doi Number: 10.1007/s10163-021-01323-3
  • Title of Journal : JOURNAL OF MATERIAL CYCLES AND WASTE MANAGEMENT
  • Keywords: Mechanical properties, Paste, Geopolymer, Ceramic powder, Binder, ALKALI-ACTIVATED MORTARS, A-S-H, FLY-ASH, COMPRESSIVE STRENGTH, MECHANICAL-PROPERTIES, NANO-SILICA, WASTE, MICROSTRUCTURE, METAKAOLIN, TEMPERATURE

Abstract

In this study, the effect of micro-SiO2 (S) and micro-Al2O3 (A) additives on the strength of geopolymer pastes was investigated. Micro S + A are added to the raw ceramic powder (CP) by weight. NaOH is used as activator. The ratio of NaOH is adjusted to contain 3%, 6% and 9% sodium (Na) in proportion to the binder weight. CP is mixed with micro S, micro A and NaOH + water in a standard cement mixer, it is placed in standard molds of 40 mm x 40 mm x 160 mm. The molds were wrapped in a fireproof oven bag and kept in the oven at 105 degrees C for 24 h. As a result of the mechanical tests on the samples compressive strength between 3.53 and 17.97 MPa were determined in the samples containing micro S and micro A. An increase in compressive strength was observed with the increase of S/A and (S + A)/CP ratio in the samples. As a result of the regression analysis, it was concluded that 1.60% for S/A, 8.52% for (S + A)/CP and 6.74% for Na in geopolymer pastes could be the optimum mixing ratio.