HS 291736 Terephthalic acid and its salts

What products does HS 291736 cover?

This subheading covers terephthalic acid and its salts, which are dicarboxylic acids and their derivatives, specifically aromatic polycarboxylic acids. Terephthalic acid is a key intermediate in the production of polyesters, particularly polyethylene terephthalate (PET), used extensively in fibers, films, and plastic bottles. The WCO Harmonized System Explanatory Notes for Chapter 29, Heading 2917, clarify that this heading encompasses polycarboxylic acids, their anhydrides, halides, peroxides, peroxyacids, and their halogenated, sulphonated, nitrated or nitrosated derivatives. USITC and EU TARIC classifications consistently apply this subheading to the pure chemical compound, terephthalic acid, and its various metallic or organic salts, provided they retain the chemical identity of a salt of terephthalic acid.

What falls outside HS 291736?

The following products are excluded from HS 291736: esters of terephthalic acid, such as dimethyl terephthalate (DMT) or bis(hydroxyethyl) terephthalate, which are classified under HS 2917.37. Polyethylene terephthalate (PET) in primary forms, being a polymer, is classified under Chapter 39, specifically HS 3907.61 or 3907.69, depending on its viscosity or other characteristics. Additionally, mixtures containing terephthalic acid but not predominantly composed of it, or prepared for specific uses not typical of a pure chemical, might be classified elsewhere based on their composition and intended function, potentially falling into Chapter 38 or other relevant chemical headings if they are not pure, separate organic compounds.

What are common classification mistakes for HS 291736?

A common error is misclassifying esters of terephthalic acid, such as dimethyl terephthalate (DMT), under HS 291736 instead of the correct subheading, HS 291737. Importers sometimes overlook the distinction between the acid/salt and its ester derivatives, leading to incorrect duty calculations and potential penalties. Another frequent mistake involves classifying terephthalic acid that is part of a mixture or formulation, rather than a pure chemical, under this subheading. According to General Interpretative Rule (GRI) 1, classification is determined by the terms of the headings and any relative section or chapter notes. For mixtures, GRI 3 may apply, often leading to classification based on the component that gives the mixture its essential character, or under a residual heading if no single component predominates.

How should importers classify products under HS 291736?

The correct procedure for classifying products under HS 291736 involves first confirming the chemical identity of the product as terephthalic acid or one of its salts, ensuring it is not an ester or a polymer. Importers and customs brokers should obtain a Certificate of Analysis (CoA) or Safety Data Sheet (SDS) from the manufacturer, which clearly states the chemical name, CAS number, and purity. This documentation is crucial for demonstrating compliance with the WCO Harmonized System and national tariff schedules like the USITC Harmonized Tariff Schedule (HTSUS) or the EU TARIC. If there is any doubt, particularly with derivatives or mixtures, seeking a binding ruling from the relevant customs authority (e.g., CBP in the US, HMRC in the UK) is highly recommended to ensure accurate and legally compliant classification, preventing costly errors and delays.