Review and analysis of thermophysical properties of a sulfuric acid-water electrolyte

TL;DR

This paper critically reviews and analyzes the thermophysical properties of sulfuric acid-water mixtures, providing new parametrizations and experimental data for density, viscosity, refraction index, and expansion coefficients across various conditions.

Contribution

It introduces a simplified density parametrization with fewer coefficients and extends the analysis over a broader temperature and concentration range.

Findings

New density equation with fewer coefficients

Good agreement with literature measurements

Extended temperature and concentration analysis

Abstract

In this work, we have performed a critical review of the thermophysical properties of sulfuric acid-water mixtures. The thermophysical properties analyzed are density, viscosity, refraction index, thermal expansion coefficient, and mass expansion coefficient. The density of the sulfuric acid-water mixture has been measured for different mass fractions, w = 0.1-0.4, over a broad temperatura range, T = 273.15-333.15 K. A new parametrization of the density has been performed using a least-squares method. In this parametrization, the number of coefficients has been reduced with respect to previous works. Moreover, this new equation has been analyzed in an extended region of temperature and concentration in the following ranges: w = 0-0.1 and T = 233.15-373.15 K. The coefficients of thermal and mass expansion have also been calculated experimentally, and a linear relation of the density has been determined as a function of the variations in temperature and concentration. In addition, viscosity and refraction index measurements have been performed at 298.15 and 293.15 K, respectively. Our results have been checked against measurements in the literature (review) and show good correspondence.