Project Details Assessment of Reliability and Uncertainty of Solubility Data

Project No.:
Start Date:
10 May 2022
End Date:


The objective of this project is to organize a workshop that will give fundamental and practical knowledge on good practices for phase equilibria measurements (in particular solubility), data analysis, and reporting high quality data to the scientific community in the area. The ultimate goal is to increase the number of IUPAC projects proposals and simultaneously diversify the subjects and areas of application. The publication of a report in Pure and Applied Chemistry and/or Journal of Solution Chemistry is planned and to share direct and practical high-level knowledge to the scientific community in the area.

Strategic value:
A workshop is scheduled during the International Symposium on Solubility Phenomena and Related Equilibrium Processes (ISSP), to be held in Bragança from 4-9 September 2022. ISSP20 is a symposium endorsed by IUPAC and one of the major activities of the SSED. The fundamental role of IUPAC as the major authoritative entity in the world to establish references in chemistry will be highlighted. In particular, as it concerns collection and critical assessment of solubility and equilibrium data, this workshop is a route to attract new members to the SSED activities.


Experimental data on thermodynamic properties of pure compounds and mixtures, including solubilities, are a crucial part of any industrial design (e.g., development or optimization of chemical, separation, and transport processes). Before using such data in any application, it is essential to assess their reliability. Uncertainty is an important attribute of any numerical data. Uncertainty estimates are reported in most scientific publications nowadays, but how reliable are they? The practice shows that they cannot be blindly trusted and should be verified. General ways of thermodynamic data validation, which give an idea about the magnitude of possible errors in the reported data, are discussed by Diky et al. [1] and will be summarized during the workshop with a focus on solubility data. To facilitate verification of experimental methods and equipment for phase equilibrium measurements, an IUPAC project by Bazyleva et al [2] suggests reference systems and solubility data for them. This aspect will be also covered at the workshop. Some statistics of the observations from the literature will be given and representative cases will be shown. The participants will be encouraged to share their experience and ideas on the following topics:
– use of solubility data and effects of erroneous data on applications;
– types and reasons of errors;
– testing of experimental methods and equipment;
– practice of verification of published solubility data;
– building uncertainty budgets for own measurements and evaluations;
– existing problems and possibilities to improve the situation; and
– collaboration opportunities.

[1] Vladimir Diky, Ala Bazyleva, Eugene Paulechka, Joseph W Magee, Vikina Martinez, Demian Riccardi, Kenneth Kroenlein. Validation of thermophysical data for scientific and engineering applications. J. Chem. Thermodyn. 2019; 133:208-222.

[2] Ala Bazyleva et al. Recommended Reference Materials for Phase Equilibrium Studies. IUPAC Project 2011-037-2-100.


Page last updated 10 May 2022