Effect of Cu2+ on the nucleation kinetics and crystallization of rod-shaped CaSO4·2H2O in aqueous solution

Xiangbin Sun; Xianshun Wang; Genlei Zhang; Peng Cui; Hao Shen

doi:10.1039/c9ra07640a

Effect of Cu²⁺ on the nucleation kinetics and crystallization of rod-shaped CaSO₄·2H₂O in aqueous solution

RSC Adv. 2019 Nov 5;9(62):36020-36026. doi: 10.1039/c9ra07640a. eCollection 2019 Nov 4.

Authors

Xiangbin Sun¹, Xianshun Wang¹, Genlei Zhang^{1

2

3}, Peng Cui¹, Hao Shen³

Affiliations

¹ School of Chemistry and Chemical Engineering, Anhui Province Key Laboratory of Controllable Chemistry Reaction and Material Chemical Engineering, Hefei University of Technology Hefei 230009 China genleizhang@hfut.edu.cn cuipeng@hfut.edu.cn.
² School of Materials Science and Engineering, Hefei University of Technology Hefei 230009 China.
³ Anhui Liuguo Chemical Co. Ltd Tongling 244021 China.

Abstract

In this study, a simple and efficient strategy is developed to synthesize rod-like CaSO₄·2H₂O (DH) crystals with tunable aspect ratio in aqueous solution using Cu²⁺ as modifier. The aspect ratio and length of the DH crystals are effectively reduced to 5.7 : 1 and about 35 μm in the presence of Cu²⁺, respectively. The interfacial tension value (γ) in the aqueous solution is improved significantly with the assistance of Cu²⁺, yet the nucleation rate (J) of the DH crystal is decreased sharply. The interfacial tension value (γ) in the aqueous solution is improved and the nucleation rate (J) of the DH crystal is drastically decreased due to the introduction of Cu²⁺, leading to the induction time of the DH crystallization being extended from 4 min to 25 min. The diversification of morphology for the DH crystals is incited by the changes of nucleation kinetics and Cu²⁺ incorporated into the crystal lattice, affecting the crystal growth habit, and finally controlling the growth of DH crystals in aqueous solution.