Critical Locus of Aqueous Solutions of Sodium Chloride Revisited

Abstract

There exists a formulation for the critical locus of aqueous solution of NaCl recommended by the International Association for the Properties of Water and Steam. In this article, we present slightly modified equations for the critical parameters of H 2 O + NaCl that incorporate a non-analytic concentration dependence predicted by theory.

On the Elusive Links between Solution Microstructure, Dynamics, and Solvation Thermodynamics: Demystifying the Path through a Bridge over Troubled Conjectures and Misinterpretations

“…We can obtain additional insights into the near-critical solute-induced microstructural perturbation by analyzing the orthobaric-density behavior of ( ∂P / ∂x NaCl ) T ρ j o ∞ and its asymptotic limit scriptA K r = lim T , ρ j o → c r i t i c a l false( ∂ P / ∂ x i false) T ρ j o ∞ , which defines the Krichevskii parameter as illustrated in Figure . This picture offers clear evidence of the formidable challenges behind the determination of the Krichevskii parameter, where we observe a wide range of scriptA K r − values for the aqueous NaCl , resulting from the significant uncertainties in the measured quantities associated with the conventional (including critical lines, PVTx , and VLE distribution coefficient based-) methods, ,, and emphasizes the need for alternative approaches to the determination of scriptA K r involving non near-critical quantities . In addition, Figure provides confirmation on the attractive/nonvolatile , character of the near-critical NaCl hydration at infinite dilution.…”

“…Orthobaric-density dependence of the isochoric-isothermal pressure perturbation of aqueous NaCl solutions at infinite dilution within the 373.15 ≤ T σ ( K ) ≤ 573.15 temperature range, where we include the experimentally observed asymptotic values scriptA K r = lim T , ρ j o → c r i t i c a l false( ∂ P / ∂ x i false) T ρ j o ∞ , i.e ., at (ρ H 2 O o – ρ c , H 2 O o ) σ = 0 together with their sources: Abdulagatov et al, Plyasunov, Fuentevilla et al, Chialvo, and Biddle et al …”

“…In fact, it becomes obvious that (∂P/∂x NaCl ) Tρd j o ∞ is negative for all isotherms, where the corresponding concentration dependence exhibits a maximum for the isotherms T σ < 573.15K, i.e., keeping (∂P/∂x NaCl ) Tρ < 0, while that for T σ = 573.15K presents an inflection such that (∂P/∂x NaCl ) Tρ crosses the LR − IS line and becomes positive at m i ≅ 4.0. We can obtain additional insights into the near-critical solute-induced microstructural perturbation by analyzing the orthobaric-density behavior of (∂P/∂x NaCl ) Tρd j o ∞ and its asymptotic limit ) σ = 0 together with their sources: Abdulagatov et al, 139 Plyasunov, 136 Fuentevilla et al, 138 Chialvo, 123 with the conventional (including critical lines, PVTx, and VLE distribution coefficient based-) methods, 136,138,139 and emphasizes the need for alternative approaches to the determination of Kr involving non near-critical quantities. 123 In addition, Figure 9 provides confirmation on the attractive/nonvolatile 8,106 character of the near-critical NaCl hydration at infinite dilution.…”

Ionic Vapor Composition in Critical and Supercritical States of Strongly Interacting Ionic Compounds

“…Ionic compounds (ICs) are omnipresent in chemistry. They are generally known for lower volatility and flammability and a larger liquid-state temperature range, as compared to molecular compounds. − ICs can be inorganic, organic, and mixed. For instance, many room-temperature ionic liquids (RTILs) − comprise an organic cation and inorganic anion, whereas inorganic crystals are essential for the Earth crust.…”