Leaching Kinetics of Chevreul's Salt in Ammonium Chloride

The study investigated the leaching kinetics of Chevreul's salt in ammonium chloride solutions by mechanical agitation experimental system. Reaction temperature, the concentration of ammonium chloride, stirring speed, and the solid-liquid ratio were selected as parameters. Experimental results were correlated using linear regression implemented in the statistical package program. The effect of parameters on Chevreul salt solubility was examined, and integrated rate expression of dissolution rate was found using kinetic models in solid-liquid heterogeneous reactions. The results revealed that the dissolution rate of Chevreul's salt decreased. At the same time, reaction temperature, concentration of ammonium chloride and stirring speed increased while dissolution rate decreased with the increase of the solid-liquid ratio. Based on the result of the applications of the obtained experimental results to the kinetic models, we can deduce that Chevreul's salt dissolution rate is controlled by diffusion through the ash (or product) layer. The activation energy of the dissolution reaction was 17.83 kJ/mol. The integrated rate expression, along with the effects of parameters on Chevreul's salt solubility, was found to be as follows:

1 - 3(1-X)^2/3 + 2(1-X) = [2,96.10¹³.(CA)^3,08 .(S/L)^-0,38.(W)^1,23 e -9001,2 / T ] . t