ISSN:
1432-0614
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Summary Zoogloea ramigera 115 cells were immobilized into beads of calcium alginate and used in air-bubbled column reactors to remove cadmium (Cd), zinc (Zn), manganese (Mn), lead (Pb), copper (Cu) and strontium (Sr) from dilute and concentrated solutions. By placing three bubble columns in sequence it was possible to achieve Cd adsorption efficiencies of 99% or greater. During ten applications of approximately 100 μg·ml-1 Cd to three reactors in sequence, the immobilized Z. ramigera adsorbed 99.9% of the metal. The efficiency of the first column decreased from 92.2% on the first day to 53.8% on the tenth day, but the overall efficiency remained high because of the other two reactors. Exposure of bubble columns to mixed metal solutions yielded similar results. Cd, Zn, Mn, Cu, and Sr were adsorbed at 95.9% or better when concentrations in the mixtures ranged from 12 to 117 μg·ml-1 per metal. Pb was the least efficiently adsorbed metal with 81.3% and 74.7% removed from solutions containing 12 and 23 μg·ml-1, Pb respectively. Recovery and concentration of the metals was possible with nitrilotriacetic acid (NTA) treatment; which desorbed 〉77% of the accumulated Cd from the immobilized cells. Recovery of metals from beads which had been exposed to mixed metals depended on the metal; only 5.8% of the adsorbed Sr was recovered, but 98.3% of Zn was desorbed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00270805
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