Summary: | 碩士 === 國防大學理工學院 === 應用化學碩士班 === 98 === The type 62A filter of military gas mask have excellent performance, which can effectively filter all kinds of chemical warfare agents, but contain heavy metals in dip-type activated carbon. Therefore, the dip-type activated carbon must be recovered when its storage time is over. This study investigated the extraction efficiency of heavy metals in the activated carbon via supercritical CO2 fluid combined with chelating agent EDTA to assess the regeneration and reuse of activated carbon over the storage time. Using the metal chelating agents conducted with military activated carbon to form the less polar metal chelates, and then the chelates is extracted by supercritical CO2 fluid, which the experimental temperature and pressure were changed to study the effect of extraction. After the extraction process, the residual heavy metals in the activated carbon were leached using agua regia digestion method. Finally, the contents of residual heavy metals were detected by the ICP. Experimental results show that the extraction efficiency of heavy metals in metal chelates extracted by supercritical CO2 fluid is increasing by increasing the extraction temperature and pressure. Therefore, the extraction of heavy metals via supercritical CO2 fluid combined with chelating agent is feasible.
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