Japan Geoscience Union Meeting 2016

Presentation information

Poster

Symbol M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS12] Interface- and nano-phenomena on crystal growth and dissolution

Sun. May 22, 2016 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall HALL6)

Convener:*Yuki Kimura(Institute of Low Temperature Science, Hokkaido University), Hitoshi Miura(Graduate School of Natural Sciences, Department of Information and Biological Sciences, Nagoya City University), Katsuo Tsukamoto(Graduate School of Engineering, Osaka University), Hisao Satoh(Naka Energy Research Laboratory, Mitsubishi Materials Corporation)

5:15 PM - 6:30 PM

[MIS12-P05] Visualization of pH change around calcium carbonate crystals during dissolution and growth

*Jun Kawano1, Takashi Toyofuku2, Yukiko Nagai2, Sachiko Kawada2, Risa Itagaki1, Takaya Nagai1 (1.Faculty of Science, Hokkaido University, 2.JAMSTEC)

Keywords:calcium carbonate, dissolution, pH

For the investigation of the growth and dissolution of calcium carbonate, CaCO3, it is important to understand how carbonate and bicarbonate ions behave in these processes. The pH monitoring of a solution during CaCO3 growth or dissolution is a useful technique for this purpose, and actually in a number of the previous studies, the pH measurements of bulk solution during the growth have been performed. However, to clarify the detail process on the surface, especially the behavior of bicarbonate ions, regional change of pH just above the crystal surface should be monitored. Recently, we have started an attempt to visualize the distribution of pH around CaCO3 crystals which inorganically grows or dissolves, by applying the method used for the research on the biogenic calcification of foraminifers. We have succeeded to detect the pH change near a dissolved calcite surface, which may provide new insights into both inorganic and biogenic formation mechanism of CaCO3.