Experimental study of mechanistic factors influencing solvent-driven fractional crystallization of calcium sulfate
- Idaho National Laboratory (INL), Idaho Falls, ID (United States)
To advance dimethyl ether-driven fractional crystallization (DME-FC), a more sustainable method of water treatment and mineral recovery, a range of chemical equilibria were measured. These include varying concentrations of miscible organic solvents (MOS) used to experimentally measure the solvent-induced solid-liquid equilibrium (SLE) of calcium sulfate (CaSO4) in water. Seven MOS, including dimethyl ether (DME), acetonitrile (MeCN), 1,4-dioxane, tetrahydrofuran (THF), acetone, ethanol, and diethylamine, were screened to establish trends associated with molecular volume, functional groups, and physical properties. The effect of MOS on CaSO4 removal differed at concentrations <0.15 mol fraction MOS; MOS with greater molecular volume (THF, 1,4-dioxane, and diethylamine) induced greater CaSO4 precipitation on a per mole basis. The solvent-induced SLE for all MOS converged between 0.15 and 0.2 mol fraction MOS, reaching a CaSO4 concentration consistent with a water to MOS hydration ratio of 5:1 to 6:1, which may correspond to the solvent generating a solution-based pseudo-clathrate structure with continuity within the solution. Finally, solution pseudo-clathrate structures provide a mechanistic basis for DME-FC.
- Research Organization:
- Idaho National Laboratory (INL), Idaho Falls, ID (United States)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
- Grant/Contract Number:
- AC07-05ID14517
- OSTI ID:
- 2476242
- Report Number(s):
- INL/JOU-23-75038-Rev000
- Journal Information:
- Desalination, Vol. 579, Issue -; ISSN 0011-9164
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Production of levoglucosenone and 5-hydroxymethylfurfural from cellulose in polar aprotic solvent–water mixtures