DISSOLUTION KINETICS OF PHOSPHATE ORE IN SO2-SATURATED WATER

In this study, the dissolution of phosphate ore from Mazidagi-Mardin, Turkey, the products formed, and the dissolution kinetics were investigated in SO2-saturated water. In experiments, particle size, stirring speed, solid/liquid ratio, and temperature were chosen as parameters. It was determined by X-ray diffractometer that the final solid product contains CaHPO4.2H(2)O, Ca-3(SO3)(2).SO4.12H(2)O, and CaSO4.2H(2)O. It was observed that the dissolution rate increased with the increase in stirring speed and reaction temperature, and with the decrease in particle size and solid/liquid ratio. A semiempirical mathematical model in the following form, including the effect of the parameters was established to express the dissolution kinetics of phosphate ore: -ln(1 - X) = 35.874D(-0.512)w(0.380).(S/L)(-0.825)e(-2575/Tt0.781), where X is the conversion fraction of the ore, w is stirring speed, D is particle size, and S/L is the solid/liquid ratio in weight. The activation energy for the process was found to be 21 408.55 J mol(-1).