4702.00.00.20 - Sulfite

This HTS category, 4702.00.00.20, specifically encompasses chemical wood pulp classified as dissolving grades and manufactured using the sulfite pulping process. Dissolving grades of wood pulp are characterized by their high alpha-cellulose content and low hemicellulose content, making them suitable for chemical conversion into regenerated cellulose products such as rayon, cellophane, and cellulose derivatives. The defining characteristic of this classification is the sulfite pulping method, which utilizes sulfurous acid or its salts to break down lignin and separate cellulose fibers from wood.

This classification is distinct from its sibling category, 4702.00.00.40, which covers chemical wood pulp of dissolving grades produced via the sulfate or soda pulping process. The key differentiator lies in the chemical reagents and methodologies employed in the pulping process. While both categories cover dissolving grades of wood pulp, the sulfite process yields pulp with specific chemical and physical properties that distinguish it from pulp produced through alkaline pulping methods. This distinction is crucial for accurate customs declaration and tariff assessment, as different pulping processes can influence the final application and value of the pulp.

As this is a leaf node within the HTS, there are no further subcategories. Therefore, the classification rests on the precise identification of wood pulp as a dissolving grade and confirmation that the sulfite pulping process was utilized in its manufacture. Importers and exporters should ensure that documentation clearly indicates the pulping method to facilitate accurate classification under this specific HTS code.