摘要 |
A method is disclosed for immobilizing material contaminated with heavy metal ions, said metal ions in a liquid environment being allowed to react with a metal-complexing agent with the formation of a metal complex, the metal-complex formed being mixed, in the presence of water, with an inorganic, hydraulic binder comprising blast furnace slag cement, fly ash cement or a combination thereof to form a matrix having reductive properties in the form of a hard, rocklike material, which method is characterized in that said metal complex is formed in the presence of a metal-complex bond activator. Said metal-complex bond activator is preferably a water-soluble salt of a transition metal element, expediently ferric chloride or manganese sulphate. The invention also relates to a fixant for immobilizing heavy metal ions comprised in waste material. |