Abstract:

It’s significant to comprehensively utilize abundant water-unsolubility potass resource for solving the shortage of bauxite and sylvite in China. The sintering reaction process of nepheline syenite collected from Gejiu, Yunnan Province, is studied, with sodium carbonate as the additive. It is suggested that the nepheline syenite be sintered at 1 103 K for one hour, with the rate of the additive(sodium carbonate) as 1∶0.75, the decomposition rate of minerals in the nepheline syenite could up to 98.0%.  Dynamics of the thermal decompose of nepheline syenite were explored, and the results indicate the process fit Crank-Ginstling-Braunshtein equation, and all apparent activation energy 78.75 kJ/mol for the decomposing reactions was derived from experimental data. According to the Arrhenius equation, the reacting time is prospected. It is concluded that solid film, which increases thickness of ion penetrating and diffuseing, causes temporal error between theoretic and practical reaction.

Key words: nepheline syenite, sintering reaction process, thermodynamic, dynamics, bauxite deposits, sylvite, Gejiu