2021 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)

Presentation information

Oral presentation

R4: Mineral sciences of the Earth surface

Thu. Sep 16, 2021 2:00 PM - 5:15 PM Zoom Session 3

Chairperson:Keisuke Fukushi(Kanazawa University), Tadashi Yokoyama(Hiroshima University), Jun Kawano(Hokkaido University), Hiroshi Sakuma(NIMS), Satoshi Utsunomiya(Kyushu University)

4:15 PM - 4:30 PM

[R4-09] Formation conditions of calcium carbonate hemihydrate

*Mai Suyama1, Keisuke Fukushi1, Takuma Kitazima1 (1. Kanazawa Uni. Sci.)

Keywords:Calcium carbonate hemihydrate, solubility, precursor, formation conditions

Calcium carbonate hemi hydrate (CCHH, CaCO3 ・1/2H2O) was synthesized for the first time by Zou et al.. It is considered that CCHH formation is possible even in the natural environment. Therefore, the purpose of this study is to clarify the formation conditions for CCHH. The results showed that CCHH can be formed if the initial solution was supersaturated with respect to CCHH. From the ionic activity, the solubility of CCHH is speculated to be between MHC and ACC. This is consistent with the alkaline lake, suggesting its presence in the natural environment, especially in the alkaline lake.