Process for removing mercury from soil
OwnerWilliam E. Fristad, Michael J. Virnig +1inventors
InventorsWilliam E. Fristad, Michael J. Virnig, Dana K. Elliott
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Abstract
Heavy metals are efficiently removed from contaminated soil by a process which comprises leaching or washing the soil with a mild leachant solution comprised of an aqueous solution of an acid and a salt. Heavy metals are also efficiently removed from paint chips by washing with an aqueous acid. The heavy metals are recovered from the leachant be cementation.
Claims9
A process for removing mercury from mercury-containing soil which comprises mixing soil and a liquid leachant composition which is an aqueous solution of (i) an acid the anion of which forms a water soluble salt with mercury;
- (ii) an acetate salt of an alkali metal, alkaline earth metal, or an ammonium acetate salt which forms water-soluble salts with mercury, and (iii) an oxidant selected from the group consisting of a persulfate salt. and a halogen in such a manner as to disperse at least a part of said soil in the leachant to form a liguid phase containing dispersed soil solids and for a period of time sufficient to transfer at least a portion of the mercury from the dispersed solids to a soluble mercury species in the liquid phase.
A process for the remediation of mercury contamination in soil which comprises:
- (1) mixing soil and a liguid leachant composition which is an aqueous solution of (i) an acid the anion of which forms a water soluble salt with mercury;
- (ii) an acetate salt of an alkali metal, alkaline earth metal, or an ammonium acetate salt which forms water-soluble salts with mercury, and (iii) an oxidant selected from the group consisting of a persulfate salt, and a halogen in such a manner as to disperse at least a part of said soil in the leachant to form a liquid phase containing dispersed soil solids and for a period of time sufficient to transfer at least a portion of the mercury from the dispersed solids to a soluble mercury species in the liquid phase;
- (2) contacting said liquid phase containing the leached, soluble mercury species with a metal selected from the group consisting of aluminum, iron, and magnesium to remove the soluble mercury species from the liquid phase.
Dependencies are inferred from the claim text.