The Solubility of Two Magnetite Powders in Oxalic Acid: Applicability of Empirical Modelling

Abstract

Phenomena-based models can be used in a predictive manner, but statistical modelling methods can also yield interesting findings and can serve as a tool for analysing the effects of different variables on the overall phenomenon. In addition, the generation of theoretical models can sometimes be limited due to the unideality of the studied system. Statistical modelling, in this case multiple-linear regression (MLR), was used to describe the effects of temperature and acid concentration on the dissolution of magnetite, Fe 3 O 4 with oxalic acid. Whereas a linear model with an interaction term was sufficient in describing the dissolution of synthetic Fe 3 O 4 , a more complex full quadratic model had to be used to describe the dissolution of industrial Fe 3 O 4 in the same conditions.