2841.90.20.00 - Ammonium perrhenate

This HTS code, 2841.90.20.00, specifically classifies ammonium perrhenate. Ammonium perrhenate is an inorganic salt formed from the reaction of perrhenic acid with ammonia. It is characterized by the presence of the perrhenate ion (ReO4-) and the ammonium cation (NH4+). This compound finds application in various industrial processes, including as a catalyst in certain chemical reactions and in the production of rhenium metal.

While this sub-heading falls under the broader category of "Salts of oxometallic or peroxometallic acids: Other," it is crucial to distinguish ammonium perrhenate from its sibling categories. For instance, vanadates (2841.90.10.00) are salts of vanadic acid, potassium stannate (2841.90.30.00) involves tin, and aluminates (2841.90.40.00) are derived from aluminum. Similarly, the chromates of zinc or lead (2841.90.45.00) are distinct based on their constituent metal ions. The "Other" category at 2841.90.50.00 serves as a residual classification for salts of oxometallic or peroxometallic acids not specifically enumerated elsewhere within the 2841.90 range, reinforcing the precise nature of ammonium perrhenate's classification here.

As a leaf node, 2841.90.20.00 does not have further subdivisions. Therefore, classification under this code is definitive for ammonium perrhenate. When classifying, customs officials will rely on the chemical identity and composition of the imported product to ensure it aligns precisely with the definition of ammonium perrhenate, rather than other perrhenates or salts of different oxometallic or peroxometallic acids.