The first development of molybdenum in the world is the Norwegian Knaben deposit. The mine mining began in 1885, because at that time, the demand for molybdenum is very small, mine when mining stopped. In the second half of the 19th century, and molybdenum in the first place in the United States begin to industrial production, only a few tons yearly. Since the 20th century, due to the increasing demand for molybdenum, molybdenum mining also expanded year by year, annual output of molybdenum VERTICAL ROLLER MILL IN CEMENT INDUSTRY in the world is growing fast, on the eve of the first world war to 100 t, 10000 t to late 30 s of this century, the late 70 s to 100000 t.
Molybdenum in abundance in the earth’s crust is about 1 x 10-6, the highest in magmatic rocks in granite type molybdenum, up to 2 x 10 to 6. Molybdenum in geochemical classification, belongs to the transitional iron. Molybdenum, generate the mining effect, the main combined with sulfur, generate molybdenite. Molybdenite (MoS2) is known in the nature’s most widely distributed in more than 30 kinds of molybdenum minerals and molybdenum content of real industrial value. Other is one of the more common molybdenum STONE CRUSHER MACHINE MANUFACTURER IN INDIA containing molybdenum minerals and iron China ([Fe3 + (MoO4) 8 · 8 h2o]), the calcium molybdate ores (CaMoO4), color wulfenite (PbMoO4), glue sulphur molybdenum (MoS2), molybdenum blue (Mo3O8 · nH2O), etc.
Molybdenite exist polymorphism, the experiment shows that the emergence of polymorphism is associated with formation temperature, 2 h type molybdenite formation temperature is higher than 3 r type molybdenite. From low to high temperature to form amorphous MoS2 to colloid MoS2, 3 hmos2 MoS2 – > 2. Temperature measurement data suggest that molybdenite formation has a wider range of temperature, but the quite high temperature until the relatively low temperature, and a large number of formed in high temperature stage. Under the hydrothermal process, MoS2 precipitation in the acidic conditions, namely the molybdenite most stable under acidic condition, when the solution to neutral, molybdenum into soluble sulfur generation of molybdate and molybdic acid salt and activity again. Under the condition of low temperature and room temperature, Mo4 + in strong acid reductive environment to generate glue sulphur molybdenum (MoS2), it is after oxidation product of molybdenum blue (Mo3O8 · nH2O). Exogenous role, molybdenum is Mo6 +, with strong activity. It is similar to uranium, in close to neutral or alkaline stable transition of oxidation and reduction environment, thus producing a variety of uranium molybdate salt content, such as molybdenum uranium [(UO2) MoO4 · 4 h2o], molybdenum calcium uranium [Ca (UO2) 3 (MoO4) (OH) 2 · 11 h2o], etc. Iron molybdenum STAMP MILL FOR SALE IN SOUTH AFRICA degrees [Fe2 (MoO4) 3 · nH2O] is sulfide ores in the acidic conditions (pH = 3 ~ 5) form the common minerals. Color wulfenite is molybdenum lead-zinc mine under neutral conditions.
Ionic radius of molybdenum rhenium with close, reason often replacement enrichment s.h. molybdenum and molybdenum, become the main source of rhenium used in industry. The rhenium content molybdenite often with type 3 r content in molybdenite and ore-forming solution is related to the rhenium content.
