Work

Activity coefficients and phase equilibria of NaCl–NaI–H2O at 288.15 K

Year: 2025

Type: article

Abstract: The Nanyishan region of the Qaidam Basin is widely known for its extensive oilfield brine resources and substantial reserves. It contains not only sodium , potassium, calcium, and boron but also low concentrations of elements such as Li, Rb, Cs, Br, and I, which makes it exceptionally valuable for thorough development and application. The research on the thermodynamical properties of the coexisting NaCl and NaI in solution and their phase equilibrium relationships is essential. In this work, the mean activity coefficients of NaI in the NaCl–NaI–H 2 O mixed solution at 288.15 K were measured using the cell potential method. Additionally, the thermodynamic properties of this mixed solution were calculated using the Pitzer model. The phase equilibria of the ternary system at 288.15 K were determined using the isothermal dissolution equilibrium method . Finally, the solubility prediction of the NaCl–NaI–H 2 O system was carried out with obtained ion interaction parameters, and the calculated results were in better agreement with the experimental values. This demonstrates the reliability of activity coefficient and solubility data, and these key thermodynamic data can provide fundamental support for comprehensive utilization technology of liquid mineral resources.

Source: Journal of Molecular Liquids

DOI: 10.1016/j.molliq.2025.127267

Authors: Hong-Bao Ren, Shi-Hua Sang, Rui–Zhi Cui, Guo-Liang Nie, Kuang-Yi Zhu

Institutions: Chengdu University of Technology, Chinese Academy of Sciences, Qinghai Institute of Salt Lakes

Language: English

Topic: Chemical and Physical Properties in Aqueous Solutions

Subfield: Filtration and Separation

Field: Chemical Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,480

Funders: National Natural Science Foundation of China, Natural Science Foundation of Qinghai