Water Activity and Freezing Points in Aqueous Solutions of Manganese Nitrate: Experimental and Modeling

Research output: Contribution to journalArticleScientificpeer-review

Researchers

Research units

  • University Hassan 1
  • Polytechnic Institute of Bragança
  • FCG Design and Engineering
  • National School of Mines of Rabat

Abstract

The water activities of manganese nitrate solutions were measured using a humidity sensor instrument up to almost the saturation molality at 298.15 K; the thermodynamic properties of the system were described by the Pitzer model and specific interaction theory (SIT). The evaluation of the ion interaction parameters for the Pitzer model and SIT were carried out using experimental freezing points and osmotic coefficients of manganese nitrate aqueous solutions, collected from the open literature, and the water activity data measured in this work. A set of Pitzer and SIT parameters were estimated using a temperature dependency, that enables us to cover wider temperature ranges, and consequently calculate system properties to higher molalities. Both approaches represent very satisfactorily, and with similar accuracy, the experimental data and the calculated manganese nitrate molal activity coefficients are comparable to those already published for analogous systems. Additionally, the Pitzer model was also able to calculate the ice curve and the solubility branch of manganese nitrate hexahydrate up to a salt solution 6.5 mol·kg−1.

Details

Original languageEnglish
Pages (from-to)774-786
Number of pages13
JournalJournal of Solution Chemistry
Volume47
Issue number4
Publication statusPublished - 1 Apr 2018
MoE publication typeA1 Journal article-refereed

    Research areas

  • Freezing points, Osmotic coefficient, Pitzer, SIT, Solubility

ID: 19968649