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Magnesium Oxide Polymerization Catalyst from China

High-purity MgO powder serving as catalyst in polypropylene production. Classified in 3815.90.3000 for its wholly inorganic composition and role as reaction initiator.

Duty Rate — China → United States

37.5%

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)
9903.05.3112.5%Section 301 (forced labor) — additional 12.5% ad valorem on products of China

Import Tips

Surface area specifications (>100m²/g) distinguish catalytic grade from refractory grade

Include polymerization reaction data demonstrating accelerator function

Antidumping duties may apply from certain origins; verify scope rulings