Beta-spodumene:Na2CO3:NaCl system calcination: A kinetic study of the conversion to lithium salt

[Display omitted] •Kinetic model of calcination between beta-spodumene and alkaline salts.•Li2CO3 conversion is proportional to Li:Na ratio and inversely to calcination rate.•Mineral thermal decomposition occurs by fluid deposition and precipitation.•Beta-spodumene dissolution occurs by diffusion and chemoselective exchange reaction.•Kinetic modeling of pseudo-second order approaches the literature equilibrium data. The basic objective of the work was to evaluate the calcination step in the lithium extraction process and to obtain a kinetic model that would adjust the experimental data for the reaction of the carbonate recovery during the processing of beta-spodumene, activated by melting with sodium carbonate/sodium chloride. In this work there were obtained activation energy values using experimental data obtained from the treatment of complex systems such as minerals. This is of interest because of the contribution it makes to the field of physical chemistry. Some of the main results indicated that the best molar ratio was 3Li2O:1Na2CO3 + 5% w/w NaCl in the conversion to Li2CO3 with approximate 70% Li yield, using a 823–923 K range with a calcination cycle of 120 min. The kinetic results indicated that the pseudo-second-order kinetic modeling fits the equilibrium data well under employed temperature conditions on literature, based on second stage of reaction mechanism (chemoselective exchange reaction).