TY - JOUR
T1 - Effect of pH on formation of single-phase vaterite
AU - Kogo, Mitsuaki
AU - Umegaki, Tetsuo
AU - Kojima, Yoshiyuki
N1 - Publisher Copyright:
© 2019
PY - 2019/7/1
Y1 - 2019/7/1
N2 - This paper reports on the effect of pH on polymorphism of calcium carbonate (vaterite) formed in the CaCl 2 -Na 2 CO 3 -H 2 O reaction system. The initial pH of CaCl 2 aqueous solution was adjusted to the initial pH 2.0–11.3 using HCl and NH 3 aqueous solution. The initial pH was 6.5 without pH adjustment. When the reaction was carried out, amorphous calcium carbonate (ACC) was formed at the early stage of the reaction and crystallized to calcite and vatrite after 3 min of stirring. Formation ratio of vaterite at this time was 60％. Single-phase vaterite was formed at initial pH 2.0–2.5. Further, focusing on the pH during ACC crystallization. When HCO 3 − ions were 80% or more during ACC crystallization, single-phase vaterite was formed.
AB - This paper reports on the effect of pH on polymorphism of calcium carbonate (vaterite) formed in the CaCl 2 -Na 2 CO 3 -H 2 O reaction system. The initial pH of CaCl 2 aqueous solution was adjusted to the initial pH 2.0–11.3 using HCl and NH 3 aqueous solution. The initial pH was 6.5 without pH adjustment. When the reaction was carried out, amorphous calcium carbonate (ACC) was formed at the early stage of the reaction and crystallized to calcite and vatrite after 3 min of stirring. Formation ratio of vaterite at this time was 60％. Single-phase vaterite was formed at initial pH 2.0–2.5. Further, focusing on the pH during ACC crystallization. When HCO 3 − ions were 80% or more during ACC crystallization, single-phase vaterite was formed.
KW - A1. Crystal morphology
KW - A1. Crystallites
KW - A1. X-ray diffraction
KW - A2. Growth from solutions
KW - B1. Calcium compounds
KW - B1. Inorganic compounds
UR - http://www.scopus.com/inward/record.url?scp=85064280206&partnerID=8YFLogxK
U2 - 10.1016/j.jcrysgro.2019.04.005
DO - 10.1016/j.jcrysgro.2019.04.005
M3 - Article
AN - SCOPUS:85064280206
SN - 0022-0248
VL - 517
SP - 35
EP - 38
JO - Journal of Crystal Growth
JF - Journal of Crystal Growth
ER -