3402.31 - Linear alkylbenzene sulfonic acids and their salts:

This HTS category encompasses linear alkylbenzene sulfonic acids and their salts, a significant group of anionic organic surface-active agents. These compounds are characterized by a linear alkylbenzene group attached to a sulfonic acid group or its salt form. They are widely used as primary active ingredients in detergents, cleaners, and various industrial applications due to their excellent detergency, wetting, and emulsifying properties.

Within heading 3402, this category specifically deals with anionic organic surface-active agents that are not soap. While sibling category 3402.39 covers "Other" anionic surface-active agents, this section hones in on the widely utilized linear alkylbenzene sulfonates, distinguishing them by their chemical structure. This focus allows for more precise classification based on the specific molecular backbone of the surface-active agent.

The subcategories within 3402.31 further refine the classification. 3402.31.10.00 addresses aromatic or modified aromatic linear alkylbenzene sulfonic acids and their salts, typically derived from benzene rings. The residual classification, 3402.31.90.00, captures all other linear alkylbenzene sulfonic acids and their salts that do not fall under the aromatic description, ensuring comprehensive coverage of this class of surface-active agents.