INFLUENCE OF THE FE-CHLORIDE(2 IONS ON THE DISSOLUTION RATE OF POTASSIUM)

A fluidized bed crystallizer is employed to investigate dissolution ra tes of potassium chloride in the presence of Fe+2 ions at 30 degrees C . With increasing concentrations of Fe+2 ions, an initial decrease of the dissolution rates in the range between 0 and 10 ppm is followed by a gradual increase in the range between 10 and 50 ppm. The addition o f Fe+2 changes the pH level of the solution to a strongly acidic level and increases the streaming potential of the suspension. The accelera tion of the dissolution rate is attributed to the adsorption of proton s which increase the charge density of the particle and hence the thic kness of the diffusion layer will consequently be decreased.