SELECTIVE DRY REMOVAL OF MERCURY FROM WAS TE GASES

Besides the amalgamation of gaseous mercury on metal-covered carriers the chemisorptive bonding of mercury on substrates impregnated with me tal salt is another possibility to remove mercury selectively from was te gases. Therefore, the dry deposition of mercury was investigated in a laboratory set-up. Several parameters were varied such as the mercu ry concentration in the gas flow, the temperature and the flow velocit y of the gas. The concentration of mercury can be measured quasi-conti nuously by AAS cold-vapour technique. It turned out that the experimen tal results of sorption correlate to a high degree with the calculated reaction-enthalpies so that this reaction may be called a selective c hemisorption between the mercury in the waste gas current and the meta l salt of the substrate material. The thermal desorption of mercury is also successful so that the carrier is able to sorb mercury again wit hout noticeable loss of activity. Therefore, it is to be supposed that this method is qualified as a mercury-recycling procedure.