ساخت زيست صافي به منظور جذب و جداسازي نيكل پايدار و امكان سنجي براي جداسازي نيكل راديواكتيو به وسيله ريزسازواره ها

Producing Bio-Filter for Absorbing and Separating Stable Nickel and Feasibility Study to Separate Radioactive Nickel by Microorganisms

In this research work, bio absorption of nickel has been investigated by new 16 various bacterial strains isolated from Ramsar warm springs. As the obtained results show a strain of gram negative cocobacilluse bacteria is highly capable to take up nickel in optimum pH about 6. The effect of nickel solution concentrations in 20-200 ppm have been studied. Uptake capacity of bacterial biomass regarding to concentrations below 150ppm is most highly and nearly constant, but it will be decreased over 150 ppm, and in 200 ppm absoption of nickel reaches to near zero. No nickel was taken up by bacterial biomass. Further studies showed that after 60 minutes of contact time, nickel uptake reaches maximum by 53%. Considering the uptake mechanism revealed that biosorption was very limited and the uptake mainly occurs through accumulation dependent on metabolic activities. Also the results show that the presence of the other captions such as Zn2+, Cu2+ and Pb2+ is ineffective to biological uptake of nickel. Nickel taken up by biomass can be easily recovered by HNO3 with the concentration of O.IM.