Empirical Prediction of Alumina Dissolution Rate in a Cryolitic Melt: Comparison with the Existing Literature

There are numerous studies published in the literature related to alumina dissolution rate in cryolite melts. However, such studies cover a broad range of results given in various formats. A new empirical equation was developed based on the results of an extensive parametric study using the gravimetric method on alumina disks. A comparison between this model shows large differences from the existing literature. This paper describes and discusses these differences. Most of the variation is caused by three main parameters strongly influencing the alumina dissolution kinetics. First, there is the alumina content and its morphology. Secondly, there is the mass and heat flow around the sample inherent to the experimental methods that were used. And thirdly, the influence of the additives concentration in the bath was identified as a strong contributor to explain the reported differences