Insights into the Role of Na⁺ on the Transformation of Gypsum into α-Hemihydrate Whiskers in Alcohol-Water Systems.

ABSTRACT: Alcohol-water solution-mediated transformation of gypsum into α-hemihydrate (α-HH) whiskers provides a green alternative for the high-value-added recycling of flue gas desulfurization (FGD) gypsum. However, the role of non-lattice cations during the transformation is still unclear. We report an evolution from "boosting-retarding" to "boosting-retarding-boosting" and finally to "boosting only" effect of non-lattice Na⁺ functioned by the concentration of ethylene glycol (EG) in water solutions. The driving force increased almost linearly upon the introduction of Na⁺ through the formation of ion pairs, and a higher slope was obtained at a higher EG concentration. Adsorption of Na⁺ ions and solidification of eugsterite on gypsum surfaces blocked the nucleation

SUBMITTER: Fu H 

PROVIDER: S-EPMC9096823 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature