(181c) Thermodynamic Modeling of HCl-H2so4-H2o Ternary System with Electrolyte NRTL Model

The hydrochloric acid-sulfuric acid-nitric acid system plays a critical role in stratospheric aerosol formation which leads to ozone layer deposition. Recently, this mixed acid system has gained a lot of attention in chemical nitration processes for energetic materials and in recovering noble metals from electronic waste. It is therefore important to develop for the mixed acid system a comprehensive thermodynamic model which could accurately represent various thermodynamic properties such as vapor pressure, molar enthalpy, molar heat capacity, and salt solubility. Our previous work [1] reported a comprehensive thermodynamic model for the HNO₃-H₂SO₄-H₂O ternary system based on the electrolyte NRTL model [2]. In this work, we extend this work for the HCl-H₂SO₄-H₂O ternary system with a temperature range of 273 to 373 K and H₂SO₄ concentration from 0 to 100 wt%. The model should be very useful in supporting heat and mass balance calculations and process simulation for processes involving HCl and H₂SO₄.

Keywords:

Hydrochloric acid, Sulfuric acid, Electrolyte NRTL model

References:

[1] M. Wang, H. Kaur, C.-C. Chen, “Thermodynamic Representation of Nitric Acid-Sulfuric Acid-Water Ternary System,” manuscript submitted to AIChE Journal (2016)

[2] Y. Song, C.-C. Chen, “Symmetric Electrolyte Nonrandom Two-Liquid Activity Coefficient Model,” Industrial & Engineering Chemistry Research, 48 (2009) 7788-7797