Volumetric Properties of the Dilute Aqueous Solution of Yttrium Sulfate from 283.15 to 363.15 K at 101.325 kPa

Abstract To better use rare earth element resources in geothermal water, it is essential to understand the volumetric property and the ion-interaction of the rare earth element aqueous solution systems. In this paper, the densities of aqueous Y 2 (SO 4 ) 3 from 0.00405 to 0.04071 mol kg −1 at 283.15 to 363.15 K were measured using an Anton Paar Digital vibrating-tube densimeter. Apparent molar volumes ( V ϕ ) and the coefficient of thermal expansion (α) were obtained based on the experimental density data, and the diagrams of the apparent molar volume and coefficient of thermal expansion of Y 2 (SO 4 ) 3 (aq) against temperature ( T ) and molality ( m ) in the binary system were revealed. The Pitzer single-salt parameters \({{(\beta }}_{{{\text{MX}}}}^{{(0)v}},{{\beta }}_{{{\text{MX}}}}^{{(1)v}},{{\beta }}_{{{\text{MX}}}}^{{(2)v}}\,\,{\text{and}}\,\,C_{{{\text{MX}}}}^{v})\) for Y 2 (SO 4 ) 3 and their temperature-dependent correlation F ( i , p , T ) = a 1 + a 2 ln( T /298.15) + a 3 ( T − 298.15) + a 4 /(620 − T ) + a 5 /( T − 227) (where T is temperature in Kelvin, a i are the correlation coefficients) for Y 2 (SO 4 ) 3 were obtained for the first time.