Research on the Removal of Impurities from Crude Nickel by Vacuum Distillation

The removal of impurity elements from crude nickel by vacuum distillation was carried out at the temperature 1773K∼1973K and the pressure less than 10 Pa using crude nickel(≥99.9%)as raw materials. A series of results of the impurity elements were obtained under the experimental conditions aforementioned.The experimental values βi andγio of the product were also calculted in this paper. The seperation of certain impurities from main element nickel was disscussed from the viewpoint of thermodynamics and alloy composition. Nickel (≥99.99%) was obtained and the purification and impurity removal from crude nickel by vacuum distillation method was feasible and determined. A China Patent on this new technology was also authorized. We consider that the vacuum distillation process of nickel can serve as a pretreatment step for the prepartion of highpurity nickel, and can relieve the following purification of the electrolyte, so that the whole process of preparation of the high-purity nickel is simplified, energy consumption and environmental pollution are reduced. Therefore, the vacuum distillation process is a green metallurgical method.