CPV code 24311400 designates Hydrogen chloride, inorganic acids, silicon dioxide and sulphur dioxide in the Common Procurement Vocabulary (CPV 2008), the EU classification used to describe the subject of public contracts.
24311400 sits under 24311000 (Chemical elements, inorganic acids and compounds) and groups 7 more specific sub-codes. When classifying a tender, choose the narrowest code that still covers the full subject of the contract.