摘要
Dissolution rates of natural scheelite were studied using batch type experimental method at 75 ℃ and pH between 1.04 and 2.46 of HCl solutions,and the kinetic mechanism of dissolution reaction was also outlined.The results show that the release rates of calcium almost keep constant at certain pH during reaction and increase with decreasing pH.It suggests that the kinetic mechanism is changed from the surface chemical reaction in the early stage to chemical reaction-diffusion controlling progress,which results in the incongruent dissolution of tungsten and calcium. The lower the pH is,the earlier the incongruent dissolution occurs.Combined with other research results,the dissolution reaction of scheelite may be in the first order with respect to hydrogen ion.