Aspect ratio-controlled preparation of α-CaSO4·0.5H2O from phosphogypsum in potassium tartrate aqueous solution

Xiangbin Sun; Genlei Zhang; Peng Cui

doi:10.1039/c9ra03569a

Aspect ratio-controlled preparation of α-CaSO₄·0.5H₂O from phosphogypsum in potassium tartrate aqueous solution

RSC Adv. 2019 Jul 11;9(38):21601-21607. doi: 10.1039/c9ra03569a.

Authors

Xiangbin Sun¹, Genlei Zhang^{1

2}, Peng Cui¹

Affiliations

¹ School of Chemistry and Chemical Engineering, Anhui Province Key Laboratory of Controllable Chemistry Reaction and Material Chemical Engineering, Hefei University of Technology Tunxi Road 193 Hefei 230009 PR China genleizhang@hfut.edu.cn cuipeng@hfut.edu.cn.
² School of Materials Science and Engineering, Hefei University of Technology Tunxi Road 193 Hefei 230009 PR China.

Abstract

In this study, a simple and efficient strategy is developed to synthesize rod-shaped α-CaSO₄·0.5H₂O crystals with tunable aspect ratio from industrial phosphogypsum only in potassium tartrate aqueous solution at a low temperature. Industrial phosphogypsum can be effectively converted into rod-shaped α-CaSO₄·0.5H₂O crystals with the assistance of potassium tartrate, and the aspect ratio of α-CaSO₄·0.5H₂O crystals gradually decreases from 52 : 1 to 1 : 1 with increasing the concentration of potassium tartrate. The formation process of the rod-shaped α-CaSO₄·0.5H₂O crystals in this system involves the dissolution of CaSO₄·2H₂O and nucleation of α-CaSO₄·0.5H₂O crystals. The tartrate ions from potassium tartrate in this system preferentially bind to (001) and (002) facets of α-CaSO₄·0.5H₂O crystals, inhibiting the growth of α-CaSO₄·0.5H₂O crystals along the c-axis and controlling its morphology and aspect ratio.