Siberian Federal University

Conducted kinetic study of dissolution of the concentrate obtained from the phosphate ore of the Rivat deposit in technical phosphoric acid. To determine the kinetics and their interaction mechanism, we studied certain parameters, such as the stirring speed (300, 500 and 700 rpm), the concentration of phosphoric anhydride (25, 30 and 35 % P2O5), as well as the temperature (60, 70 and 80 °C). It should be noted that the rate of dissolution of phosphorite concentrate increases with an increase of studied parameters. Due to the complexity of the dissolution of phosphates in mineral acids, this process has not fully explored. However, there are several different published materials on the kinetic model to describe this process, giving different expressions of the rate as a function of time. To study this process, the most suitable model is the shrinking core model. In this work, to calculate the rate constant k and the activation energy, we used solutions free of calcium sulfate