A method for outages of the heavy metal ions - complexes of polycarboxylates

摘要

A process for precipitating heavy metal ion-polycarboxylate complexes from solution, said process comprising adding to a solution containing at least one of said complexes an aqueous solution of a water soluble aluminum salt, the anion of which does not form any water soluble complexes with said heavy metal ions to be precipitated or optionally such anion-heavy metal complexes having a stability constant, expressed as their decadic logarithm, of less than 2; wherein 0.9 to 1.8 moles of aluminum ions are employed per equivalent of polycarboxylate; and adjusting the pH of the resulting reaction mixture to about 6.5 to about 9.0 with an alkali metal carbonate.