Molybdenum occurs in minerals such as wulfenite, powellite, and molybdenite. Molybdenite is the ore that is used most frequently for commercial isolation purposes. Molybdenite is a mineral which is composed of molybdenum disulfide. In order to extract molybdenum from its disulfide form, it is converted to its single sulfide form. The next isolation step involves “roasting” the sulfide to form the molybdenum oxide. The molybdenum oxide is usually then used for steel alloys.
Further isolation of the molybdenum oxide uses ammonium hydroxide and hydrogen. The molybdenum oxide is first dissolved in ammonium hydroxide to create ammonium molybdate. The ammonium molybdate is then reacted with hydrogen in a reduction reaction. The end result is pure molybdenum metal. Isolation of molybdenum is not normally carried out in a laboratory setting as the pure form is available for commercial uses; isolated molybdenum in large quantities can be toxic to some animals and needs to be handled with caution.