2809.20.00 - Phosphoric acid and polyphosphoric acids

This HTS category, 2809.20.00, specifically encompasses phosphoric acid and polyphosphoric acids, which are key inorganic compounds of phosphorus. Phosphoric acid, in its various forms (e.g., orthophosphoric acid), is a common chemical intermediary and is widely used in industries such as food and beverage, fertilizer production, and metal treatment. Polyphosphoric acids, characterized by a chain of phosphate units, also find applications in specialized chemical processes.

It is important to distinguish this category from its sibling, 2809.10.00.00, which covers diphosphorus pentaoxide. While diphosphorus pentaoxide is a precursor to phosphoric acid, this classification is for the acid itself, not its anhydrous oxide form. The defining characteristic for 2809.20.00 is the presence of the acidic functional group derived from phosphorus pentoxide and water.

Within this broad classification, further subdivisions exist to delineate specific types of polyphosphoric acids. The subcategories will provide more granular detail on these chain-like phosphorus oxyacids, which can vary in their chain length and degree of polymerization, reflecting different industrial applications and chemical properties.