N,N'-Bis(trimethylsilyl) urea; 3-(Hydroxymethylphosphinyl)-1-propanoic acid, 2-hydroxyethyl ester; and 2-Phosphonobutane-1,2,4-tricarboxylic acid and its salts
Other organo-inorganic compounds: > Other: > Other: > N,N'-Bis(trimethylsilyl) urea; 3-(Hydroxymethylphosphinyl)-1-propanoic acid, 2-hydroxyethyl ester; and 2-Phosphonobutane-1,2,4-tricarboxylic acid and its salts
Duty Rate (from China)
Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
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)
Products classified under HTS 2931.90.70.00
N,N'-Bis(trimethylsilyl) Urea
N,N'-Bis(trimethylsilyl) urea is a chemically defined organo-silicon compound containing silicon atoms directly linked to carbon, used primarily as a silylating agent in organic synthesis and as a reagent in pharmaceutical manufacturing. It falls under HTS 2931.90.70.00 as one of the specifically named organo-inorganic compounds in this statistical suffix.
3-(Hydroxymethylphosphinyl)-1-propanoic acid, 2-hydroxyethyl ester
This organo-phosphorus compound, also known as HPPA hydroxyethyl ester, features phosphorus directly bonded to carbon and is used as a phosphonate intermediate in agrochemical synthesis and flame retardants. HTS 2931.90.70.00 specifically lists this compound among named organo-inorganic chemicals per the tariff description.
2-Phosphonobutane-1,2,4-tricarboxylic acid (PBTC)
PBTC is a multifunctional organo-phosphorus chelating agent with phosphorus directly linked to carbon, widely used in water treatment, detergents, and corrosion inhibitors. It is explicitly named in HTS 2931.90.70.00 as a specific organo-inorganic compound, including its various salts.
Sodium Salt of 2-Phosphonobutane-1,2,4-tricarboxylic acid
The tetrasodium salt of PBTC is the most common commercial form, offering better water solubility for cooling water treatment and scale inhibition applications. Classified with parent acid under HTS 2931.90.70.00 per Chapter 29 inorganic salt classification rules.
Ammonium Salt of 2-Phosphonobutane-1,2,4-tricarboxylic acid
Ammonium PBTC salt provides volatility control in certain detergent and cleaning formulations where sodium salts cause residue issues. Falls under HTS 2931.90.70.00 as salt of specifically named organo-inorganic acid.
N,N'-Bis(trimethylsilyl) Urea Technical Grade
Technical grade N,N'-Bis(trimethylsilyl) urea (95%+ purity) serves as silylating reagent for carbohydrate protection in nucleoside synthesis. Specifically enumerated in HTS 2931.90.70.00 distinguishing it from general silanes.
PBTC 50% Aqueous Solution
50% PBTC in water represents standard commercial concentration for water treatment injection systems. Remains classified under HTS 2931.90.70.00 per Chapter 29 note 1(d) allowing aqueous solutions of named compounds.
3-(Hydroxymethylphosphinyl)-1-propanoic acid, 2-hydroxyethyl ester Technical
Technical grade of this named phosphinate ester used as glyphosate herbicide intermediate and polymer flame retardant monomer. HTS 2931.90.70.00 specifically identifies this exact chemical structure.
Potassium Salt of 2-Phosphonobutane-1,2,4-tricarboxylic acid
Dipotassium PBTC salt preferred in potassium-formulated cooling water treatments avoiding sodium discharge limits. Salts of specifically named acids remain in HTS 2931.90.70.00.