Effect of aluminum phase in the formation process of thaumasite

ABSTRACT

Research has shown the presence of aluminum phases can accelerate thaumasite formation. This study examines the thaumasite-ettringite solid solutions to investigate the effect of Al phases on the types and morphologies of products, the role of Al phases in the thaumasite formation and attempt to find a new analysis method. The solid solutions were synthesized at 5°C, with Al/Si ratios from 1:9 to 9:1. X-ray diffraction (XRD), scanning electron microscope-energy dispersive spectrometer (SEM+ EDS), X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance (NMR) analyses were performed on the 16-week products. Results indicate: two types of solid solutions were formed in all specimens, and their morphologies were related to their elemental compositions and types; the Al phases in ettringites can be replaced by Si to form thaumasite-ettringite solid solutions.

KEYWORDS:

• Thaumasite
• solid solution
• Al phase

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Project (GDDCE 17-7) supported by Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering, Shenzhen Durability Center for Civil Engineering, Shenzhen University [GDDCE17-7];This work was financially supported by the State Key Laboratory of Silicate Materials for Architectures (Wuhan University of Technology) SYSJJ2017-13 [SYSJJ2017-13];

Notes on contributors

Ke Kai

Kai Ke is lecturer in School of Materials and Chemical Engineering, Hubei University of Technology. He is an author of over 10 peer-reviewed scientific paper. He is currently motivated in researches involving green building materials.