Influence of temperature and solution composition on the formation of calcium sulfates--颗粒学报PARTICUOLOGY

Luo, K., Li, C., Xiang, L., Li, H., & Ning, P. (2010). Influence of temperature and solution composition on the formation of calcium sulfates. Particuology, 8(3), 240-244. https://doi.org/10.1016/j.partic.2010.01.005

Influence of temperature and solution composition on the formation of calcium sulfates

Kangbi Luo ^{a b}, Chunmei Li ^{a b}, Lan Xiang ^b *, Huping Li ^a, Ping Ning ^a

a College of Chemical Engineering, Kunming University of Science & Technology, Kunming 650224, China
b Department of Chemical Engineering, Tsinghua University, Haidian, Beijing 100084, China

10.1016/j.partic.2010.01.005

Volume 8, Issue 3, June 2010, Pages 240-244

Received 22 April 2009, Revised 28 August 2009, Accepted 18 January 2010, Available online 4 February 2010.

E-mail: xianglan@mail.tsinghua.edu.cn

Highlights

Abstract

Calcium sulfates (anhydrite and hydrates) were synthesized by mixing CaCl₂ and Na₂SO₄ solutions at room temperature followed by aging the resulting slurries at elevated temperatures. The variation of the morphology and structure of the calcium sulfates with aging temperature was investigated. Experimental results indicated that CaSO₄·2H₂O plates, CaSO₄·0.5H₂O whiskers and CaSO₄ spindles were formed at ≤100 °C, 130–160 °C and ≥170 °C, respectively. The formation and conversion of the calcium sulfates were discussed on the basis of characterization of the products and chemical analysis of the solutions. Compared to NaCl solution, pure water favors one-dimensional hydrothermal growth of CaSO₄·0.5H₂O whiskers owing to lower supersaturation.

Graphical abstract

Keywords

Calcium sulfates; Ceramics; Hydrothermal technology; Crystal growth

文章导读