2-Mercaptopropionic Acid from China
2-Mercaptopropionic acid (CH₃CH(SH)CH₂COOH) contains both carboxylic acid and thiol functions with sulfur directly bonded to carbon, classified under HTS 2930.90.4950 as other organo-sulfur acids. Meets Chapter 29 criteria for chemically defined compounds; the sulfur-carbon linkage distinguishes it from Chapter 28 inorganic acids. Used in chelating agents and metal extraction.
Duty Rate — China → United States
29.2%
Rate breakdown
9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)
9903.03.030%Articles the product of any country, as provided for in subdivision (aa)(ii) of U.S. note 2 to this subchapter
Import Tips
• Submit assay reports showing acid value and thiol content to confirm dual functionality required for heading 2930
• Ensure packaging prevents oxidation; stabilizers permitted under Chapter 29(g) for safety
• Distinguish from thioglycolic acid (specific subheading) in entry documentation