Recovery of Elemental Mercury

One other method of recovering mercury from the vapor phase is to extract mercury using a suitable solvent (e.g. toluene or chloroform) in a scrubber, e.g. a packed tower. The mercury in the solvent can be reprocessed commercially. But, the poor solubility of mercury in such solvents warrants consumption of huge quantities of solvent thus limiting the use of a packed tower process for mercury recovery. It is therefore apparent that a preconcentration step must be used to facilitate the removal and recovery of mercury from the air phase. 

The saturated adsorbent column containing Hg will be desorbed under heat and a purge medium to elute the adsorbate. The eluting gases would be condensed to recover the Hg vapor in the liquid form. The carrier gas from the condenser will also be passed through two acidified K2Cr207 baths in series to eliminate any uncondensed residual mercury. 

Preliminary experiments have shown promise for this process. However, research is incomplete at this point to present conclusive data. 

A biological process for detoxification of mercury in polluted water and sludges has been developed. Recovery of elemental mercury from the vapor phase for reuse is being studied and preliminary results show promise for the process. A full-scale process is under investigation for field/commercial application. 

Effect of cinnabar pyrite oxidation by Thiobacillus ferrooxidans and cinnabar mobilization by a mercury-resistant strain. Appl. Environ. Microbiol. 53 772-776. 

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