| The reason that the low grade crude cadmium from the system of water leaching cadmium is analyzed in this paper,the main impurity elements affecting the grade of cadmium are found out and the experimental investigation aiming at Pb & Tl that are removed difficultly is finished.The effective ways of removing impurities are obtained and the new technological process is put forward,the improvement of the grade of the crude cadmium,even the production of 2# cadmium can be realized. |