ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
The formation process of aluminum hydroxide in calcium sulfoaluminate pastes
Fei Song, Yinong Lü, Honggang Qin, Yunfei Liu, Jian Xiao, and Wenjuan Liu
College of Materials Science and Engineering, Hunan Provincial Key Laboratory of Advanced Materials for New Energy Storage and Conversion, Hunan University of Science and Technology, Xiangtan, China
Received: 9 July 2020 Accepted: 9 September 2020
Aluminum hydroxide phase (AH3) is one of the hydration products for calcium sulfoaluminate. In this paper, the microstructure and formation process of AH3 at different temperatures and water/solid ratios were investigated via scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS). The results suggest that not only a high water/solid ratio but also a high temperature promoted the formation of AH3, and changed the microstructure of AH3. The AH3 with various morphologies, formed together with ettringite and monosulfate, were found and confirmed in the pastes. The filamentous and lamellar AH3 were observed in the early stages. Then, the AH3 often gathered and grew forming smooth or lamellar spherical AH3. At last, the spherical AH3 usually continued to aggregate, forming dense or lamellar agglomerated AH3 in the later stages.
Keywords: Calcium sulfoaluminate; Hydration; Aluminum hydroxide; Ettringite; Monosulfate
Full paper is available at www.springerlink.com.
Chemical Papers 75 (3) 909–920 (2021)