文献类型：期刊文献

英文题名：Role of Aspartic Acid in the Synthesis of Spherical Vaterite by the Ca(OH)2-CO2 Reaction

作者：Luo, Jia[1];Kong, Fantao[1];Ma, Xinsheng[1]

机构：[1]E China Univ Sci & Technol, Sch Chem Engn, Natl Engn Res Ctr Ultrafine Powder, Shanghai 200237, Peoples R China

年份：2016

卷号：16

期号：2

起止页码：728

外文期刊名：CRYSTAL GROWTH & DESIGN

收录：;EI(收录号：20160701921077);WOS:【SCI-EXPANDED(收录号:WOS:000369773300024)】；

语种：英文

外文关键词：Spheres - Thermogravimetric analysis - X ray diffraction - Chelation - Scanning electron microscopy - Hydrated lime - Amino acids - Biomineralization - Fourier transform infrared spectroscopy - Carbon dioxide - Field emission microscopes - Calcium carbonate - Differential scanning calorimetry - Lime

摘要：Vaterite crystals with a spherical shape were successfully obtained by the addition of aspartic acid (Asp) in the calcium hydroxide (Ca(OH)(2))-carbon dioxide reaction system. Crystalline products were characterized by X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, and differential scanning calorimetry (TG-DSC). The experimental results indicate that the addition of Asp can inhibit the growth of calcite but promote the formation of vaterite, and the spherical vaterite CaCO3 is gradually dominant along with the increase of Asp. Meanwhile the content of the vaterite phase is prominently influenced by the reaction temperature, and the optimal temperature for vaterite is at 40 degrees C. It is proposed that vaterite is induced through the intermediate chelated by Asp and Ca(OH)(2), and then Asp is adsorbed on the surface of vaterite by chelation, preventing the metastable vaterite from transforming to calcite via a dissolution-recrystallization process. Further, the decrease of pH in the solution could reduce the chelation between Asp and Ca2+, leading to the transformation from vaterite to calcite. Hence, the study on the formation and transformation of vaterite will provide additional insight into biomineralization mechanism and industrial production.