SIMULTANEOUS REMOVING METHOD FOR HEAVY METAL IN AQUEOUS SOLUTION AND HEAVY METAL IN HEAVY METAL CHELATE COMPLEX

摘要

PURPOSE:To remove heavy metals contained in an aqueous solution and those in a heavy metal chelate complex (for example, cadmium, copper, lead, zinc) simultaneously by adding iron powder and a sulfuration agent. CONSTITUTION:The pH of an aqueous solution is adjusted to the acidic value preferably, a range of pH2-3, iron powder and further barium sulfide, as a sulfuration agent, are added, a reaction is promoted by means of a strong agitation system which enfolds air or by sending air in when agitating. The reaction is continued until the pH spontaneously rises to the value of 4-7, the pH is adjusted to the alkalinity of pH9 or more, preferably, pH9-11, by adding an alkali agent, the solution is agitated, and calcium chloride and high-molecular coagulant are added.