Section 06 Products of the chemical or allied industries 28 Inorganic chemicals; organic or inorganic compounds of precious metals, of rare-earth metals, of radioactive elements or isotopes 28 11 Other inorganic acids and other inorganic oxygen compounds of non-metals. 28 11 12 Hydrogen cyanide (hydrocyanic acid) Commodity Code Description 28 11 12 00 Hydrogen cyanide (hydrocyanic acid)