Anodising guide - 6. Disposal of chemicals

It should be obvious that used chemicals shouldn't be poured into the drain. Below you will find hints to dispose them correctly:

• Sulfuric acid
  Slowly stir lime into the acid until no more gas formation takes place. The products are then water and harmless gypsum.
• Nitric acid
  Carefully stir lime or soda into the acid until no more gas is produced. They products are water and nitrates, which e.g. can be used as nitrogen fertiliser.
• Sodium hydroxid
  Add plenty of sulfuric or acetic acid until the solution reaches pH 7 or pour the solution strongly diluted into the drain (even the usual chemical drain cleaners are almost exclusively sodium hydroxide).
• Dye baths
  Since there are used different classes of chemicals, please follow the instructions in the relevant technical data sheets.