Molybdenum Trioxide

#1 Use: Metallurgy (~75% of consumption): Added directly to steel melts (e.g., in briquette form) or used to produce ferromolybdenum (FeMo). It is the most common vehicle for introducing molybdenum into alloys (steels, cast irons, superalloys).

#2 Use: Chemical Precursor: The starting point for virtually all other molybdenum chemicals:

Ammonium Dimolybdate (ADM) / Ammonium Heptamolybdate (AHM): Intermediate for catalysts and pure metal powder.

Molybdenum Metal & Powder: Via hydrogen reduction: MoO₃ + 3H₂ → Mo + 3H₂O.

Molybdenum Disulfide (MoS₂) Lubricants: Via chemical synthesis.

#3 Use: Catalyst & Pigment:

Catalyst: Used directly or as a support in petroleum refining (e.g., for acrylonitrile production) and hydrodesulfurization catalysts (after processing to the sulfide form).

Pigments: Used to create corrosion-inhibiting pigments (e.g., zinc molybdate, calcium phosphomolybdate) for primers and paints.

Specialized Use: Smoke Suppressant: Combined with zinc oxide or other compounds in plastics (like PVC) and wire/cable coatings to act as a smoke suppressant in case of fire.

Not typically as MoO₃ itself due to its very low solubility in water. It is first processed into soluble molybdates (like sodium or ammonium molybdate), which are then used in fertilizers and foliar sprays to correct molybdenum deficiency in crops (especially legumes).