MECHANISM OF THE REMEDIATION (DETOXIFICATION) OF CHEMICALS (PESTICIDE, HEAVY METALS, OTHER TOXIC CHEMICAL COMPOUNDS)

摘要

Klebsiella pneumoniae, mercury resistant bacterial strain which is able to reduce ionic mercury to metallic mercury was isolated from wastewater of Casablanca. This strain exhibit high minimal inhibition concentrations for heavy metals such mercury 2400μM, lead 8000μM, silver 2400μM and cadmium 1000μM. This bacterium was immobilized in alginate, polyacrylamide, vermiculite and cooper beech and use for removing mercury from synthetic water polluted by mercury using a fluidized bead bioreactor. Immobilized bacterial cells of Klebsiella pneumoniae could effectively volatilize mercury and detoxify mercury compounds. Moreover, the efficiency of mercury volatilization was much greater than with the native cells. The highest cleanup and volatilization rates were obtained when Klebsiella pneumoniae was entrapped in alginate beads with cleanup rate of 100% and volatilization rate of 89%. Immobilized cells in alginate continuously volatilized mercury after 10 days without loss of activity.