2917.14 - Maleic anhydride:

This HTS category, 2917.14, specifically covers maleic anhydride. Maleic anhydride is a cyclic dicarboxylic anhydride, characterized by its chemical structure containing a double bond within a five-membered ring. It is primarily used as an intermediate in the production of various resins, coatings, agricultural chemicals, and pharmaceuticals. Its significance lies in its reactive double bond and anhydride functional group, making it a versatile building block in organic synthesis.

Distinguishing maleic anhydride from its siblings is crucial for accurate classification. While other codes within 2917 cover acyclic polycarboxylic acids and their derivatives like oxalic, adipic, azelaic, and sebacic acids, maleic anhydride is distinct due to its cyclic structure and anhydride form. These other acids are typically linear and may be classified as their free acid, salt, or ester forms, whereas 2917.14 is specifically for the anhydride of maleic acid.

To further refine classification, subcategories exist within 2917.14. The primary distinction is based on the origin of the manufacturing process. Subcategory 2917.14.10.00 is for maleic anhydride derived, in whole or in part, from benzene or other aromatic hydrocarbons. This often refers to the traditional benzene oxidation process. In contrast, subcategory 2917.14.50.00 encompasses "Other" maleic anhydride, which typically includes material produced through alternative processes, such as the oxidation of n-butane. Understanding the manufacturing route is therefore a key criterion for selecting the appropriate subheading.