Abstract:The removal of impurities in molybdenum calcine has become a new challenge for enterprises due to the cancellation of pickling. Whether the impurity minerals can be converted into soluble ions in the roasting process is of great significance for the current washing. In this paper, the traditional methods such as laser particle size analyzer and X-ray diffraction (XRD) were used to analyze the particle size, pore size and elements of molybdenum concentrate. Combined with Mineral liberation analyzer (MLA) and Factsage thermodynamic software, the changes in the occurrence forms of impurity elements during the production of molybdenum calcine were studied, and the specific path of impurity minerals transforming into soluble ions was explored. The results show that there are nanoscale pores in both molybdenum concentrate and molybdenum calcine, which will prevent washing and impurity removal. As the main insoluble impurities, aluminum potassium minerals have a great influence on the production of high purity molybdenum products, and most of them exist in the form of alkaline minerals with large molecular weight. In the roasting process of molybdenum concentrate, K-containing minerals such as Muscovite and orthoclase can be partially converted into soluble ions such as K+ and Al3+, and then removed by washing. Humidification improves the degree of conversion of orthoclase into soluble ions during roasting and is beneficial to the removal of impurities during washing.