WCO Explanatory Notes reproduced for reference. © World Customs Organization. Verify against official WCO publication.
28.14 Ammonia, anhydrous or in aqueous solution. - 28 14.10 Anhydrous ammonia 2814.20 - Ammonia in aqueous solution Ammonia is obtained either from impure arnmoniacal gas li uors produced in coal gas purification or coke works (see Explanatory Note to heading 8.25, Item (A) (3)), or by synthesis fiom hydrogen and nitrogen. This heading includes : (1) Anhydrous ammonia (NH3), a colourless gas. It is less dense than air and easily liquefied by pressure. Presented in metal cylinders. (2) Ammonia in a ueous solution (NH40H , hydroxide of a hypothetical" element" ammonium These solutions (genera ly containing 20, 27 or 34 % of NH3) afe coloui-less or yellowish li uids presented in tightly-stoppered containers. Alcoholic solutions of ammonia are exc uded (heading 38.24). (~7. r' 'I Ammonia has many uses, for exam le, in the manufacture of nitric acid and nitrates, ammonium sulphate, other ammonium salts an! nitrogenous fertilisers, sodium carbonate, cyanides, amines (e.g., naphthylamine). It emulsifies fatty matter and resins, and it acts as a detergent for removing stains, preparing polishing compounds, treating latex, removing varnish, etc. Liquefied ammonia is used in refrigerating plant.
1.- Except where the context otherwise requires, the headings of this Chapter apply only to : (a) Separate chemical elements and separate chemically defined compounds, whether or not containing impurities; (b) The products mentioned in (a) above dissolved in water; (c) The products mentioned in (a) above dissolved in other solvents provided that the solution constitutes a normal and necessary method of putting up these products adopted solely for reasons of safety or for transport and that the solvent does not render the product particularly suitable for specific use rather than for general use; (d) The products mentioned in (a), (b) or (c) above with an added stabiliser (including an anti-caking agent) necessary for their preservation or transport; (e) The products mentioned in (a), (b), (c) or (d) above with an added anti-dusting agent or a colouring substance added to facilitate their identification or for safety reasons, provided that the additions do not render the product particularly suitable for specific use rather than for general use.