Section 06 PRODUCTS OF THE CHEMICAL OR ALLIED INDUSTRIES 28 Inorganic chemicals; organic or inorganic compounds of precious metals , of rare 28 36 Carbonates; peroxocarbonates (percarbonates); commercial ammonium carbonate cont 28 36 20 28 36 20 00 Commodity Code Description 28 36 20 00 00 - Disodium carbonate 28 36 30 00 00 - Sodium hydrogencarbonate (sodium bicarbonate) 28 36 40 00 00 - Potassium carbonates 28 36 50 00 00 - Calcium carbonate 28 36 60 00 00 - Barium carbonate 28 36 91 00 00 -- Lithium carbonates 28 36 92 00 00 -- Strontium carbonate 28 36 99 00 00 -- Other