文献类型：期刊文献

英文题名：Study on crystallization of calcium carbonate from calcium sulfate and ammonium carbonate in the presence of magnesium ions

作者：Zhao, Jingcai[1];Song, Xingfu[1];Sun, Yuzhu[1];Chen, Bo[1];Yu, Jianguo[1]

机构：[1]E China Univ Sci & Technol, Natl Engn Res Ctr Integrated Utilizat Salt Lake R, Shanghai 200237, Peoples R China

年份：2015

卷号：50

期号：4

起止页码：277

外文期刊名：CRYSTAL RESEARCH AND TECHNOLOGY

收录：;EI(收录号：20151500730843);WOS:【SCI-EXPANDED(收录号:WOS:000353234300001)】；

基金：The authors greatly acknowledge the National High Technology Research and Development Program of China (No. 2011AA06A107) for financial support.

语种：英文

外文关键词：vaterite; batch crystallization; growth rate

摘要：Batch reactive crystallization of calcium carbonate (CaCO3) from ammonium carbonate ((NH4)(2)CO3) and calcium sulfate (CaSO4) was investigated in the presence of magnesium (Mg2+) ions. It was observed that Mg2+ ions partly inhibited the conversion of CaSO4 into CaCO3. When the content of Mg2+ was less than 2%, the reduction in conversion rate of CaSO4 was less than 2%, and the effect of Mg2+ ions could be ignored. Effect of impurity on crystallization kinetics of CaCO3, including the growth rate and nucleation rate, was investigated. The results revealed that when Mg2+ ions content was less than 1%, Mg2+ could promote the growth of CaCO3 and inhibit the nucleation process, which was favorable for the filtration of CaCO3.When the content of Mg2+ ions was greater than 1%, Mg2+ inhibited the growth of CaCO3, which resulted in explosion nucleation and led to a large number of particles in the solution, which was unfavorable for the filtration of CaCO3. Based on the Bransom model, the particle size distribution equations of CaCO3 were established. X-ray diffraction patterns and scanning electron microscopy images exhibited the existence of spherical vaterite of CaCO3 due to the reaction of CaSO4 with (NH4)(2)CO3 under the effect of Mg2+ ions, which was inconsistent with the results reported in the literatures.