Molybdenite
There are polytypes in molybdite. The results show that the occurrence of molybdite is related to the formation temperature. The 2H type molybdite has higher forming temperature than that of 3R type. The temperature changes from low to high to form amorphous MoS2 / 3MoS2 colloid MoS2 / 3MoS2 / 2HMoS2. The data of temperature measurement show that molybdite has a wide range of temperature, it can be formed from high temperature to relatively low temperature, and a large number of molybdite formed in the high to middle temperature stage. Under the action of hydrothermal solution, MoS2 precipitates in acidic condition, that is, molybdite is most stable in acidic condition. When the solution turns neutral, molybdenum becomes soluble thiomolybdate and molybdate. Under the conditions of low temperature and normal temperature, Mo4 forms colloidal molybdite (MoS2) in a strong acid reduction environment. The product of its oxidation is Mo3O8 ·nH2O. In exogeny, molybdenum is Mo6 and has strong activity. Similar to uranium, it is stable in a transitional environment of near neutral or partial alkaline oxidation and reduction, resulting in the formation of a variety of uranium-containing molybdate minerals, such as molybdanite [(UO2) MoO4 ·4H2O], Ca (UO2) 3 (MoO4) (OH) 2 11H2O), et al. Fe2 (MoO4) 3 ·nH2O is a common mineral formed by sulphide ore under acidic conditions (pH=3~5). Color molybdenum lead ore is the product of lead zinc ore containing molybdenum under neutral conditions. The ion radius of rhenium is similar to that of molybdenum, so molybdenum is often replaced and enriched in molybdite, thus becoming the main source of rhenium for industrial use. The rhenium content in molybdite is usually related to the 3R type content in molybdite and the rhenium content in ore-forming solution.
