Exopolymer produced by Pseudomonas aeruginosa: A super sorbent for ruthenium

ABSTRACT

Pseudomonas aeruginosa exopolymer was found to have a sorption capacity of 196.3 mg/g at 100 µg/mL of ruthenium, pH 2.8, and 30 min, which is 5–10 times higher compared to the earlier reports. Uptake mechanism was deduced using sorption studies and energy-dispersive X-ray fluorescence, proton-induced X-ray emission, scanning electron microscopy, and Fourier transform infrared spectroscopy techniques. Shrinking and volume change were observed in the morphology of the exopolymer upon ruthenium uptake. During biosorption, occurrence of ion exchange and involvement of carboxyl, ether, and alcoholic functional groups were noted. Biopolymer was found to be a potential sorbent for soluble radionuclide removal during nuclear fuel reprocessing and hazardous waste disposal.

KEYWORDS:

• Ruthenium
• biosorption
• exopolymer
• ion exchange
• Pseudomonas aeruginosa

Acknowledgements

We thank Dr J. Arunachalam, Former Head, NCCCM, BARC, for his constant support and encouragement.