Ammonium heptamolybdate tetrahydrate is the principal water-soluble molybdenum salt and the entry point for nearly every Mo-based formulation in catalyst manufacture, surface engineering, and analysis. Dissolving readily to give neutral-to-faintly-acidic solutions, it delivers molybdenum in a form compatible with impregnation, precipitation, and complexation chemistry.
Chemical Identity and Key Properties
| Property | Value |
|---|---|
| CAS Number | 12054-85-2 |
| Molecular Formula | H6MoNO2- |
| Molecular Weight | 149.95 g/mol |
| Density | 2.498 |
| Typical Purity | 81.0-83.0% MoO3 basis |
Catalyst Manufacturing
Hydrotreating (HDS/HDN) catalysts — CoMo/Al2O3 and NiMo/Al2O3 systems — are produced by impregnating shaped alumina with ammonium molybdate solutions, followed by drying and sulfidation. The heptamolybdate likewise serves acrylonitrile synthesis (bismuth molybdates) and formaldehyde-to-formic-acid Fe-Mo oxide catalysts.
Analytical and Electrochemical Uses
Classical phosphate and silicate colorimetry rely on molybdate heteropoly-acid formation; the reagent remains relevant in water-quality and steel-analysis labs. In surface finishing, molybdate chemistry contributes to black-nickel and passivation formulations.
Specification Essentials
Buyers distinguish MoO3 assay basis (typical 81.0–83.0% on an ignited basis for the tetrahydrate), chloride, sulfate, phosphate, and heavy-metal limits. Solution clarity and freedom from molybdic acid insolubles matter for catalyst impregnation lines.
Frequently Asked Questions
How is Mo content specified and verified?
As MoO3 content on an ignition basis with gravimetric or ICP verification per lot; CoreyChem provides full COA documentation with each shipment.
Is the tetrahydrate form critical?
For solution preparation the tetrahydrate is the standard assay basis; loss of water of hydration skews weighing — sealed storage preserves the defined hydrate.
Can ammonium molybdate be supplied in production volumes?
Yes, from kilogram drums upward with export packaging; custom particle-size or low-phosphate specifications are available for catalyst manufacturers.
Source from CoreyChem
CoreyChem supplies Ammonium molybdenum oxide (CAS 12054-85-2) with lot-specific COA and MSDS documentation. Custom synthesis, higher purity grades, and bulk packaging are available on request — contact our technical team with your target specification and quantity for current lead time and pricing.
