ABSTRACT
This study evaluates the bioleaching of uranium from El-Sella mineralisation by Aspergillus clavatus. A. clavatus was generally found to give the maximum bioleaching efficiency of uranium under two-step bioleaching process when a total concentration of 3% (w/v) El-Sella mineralisation was applied. Microscopic examination revealed that bioleaching negatively affected fungal vesicles, and resulted in the formation of a swollen pellet structure in the mycelium. Uranium precipitated as uranium calcium phosphate mineral (Autunite) crystals on the surface of hyphae. Finally, the purity of uranium assayed was 73.19% in sodium diuranate. In conclusion, the optimum conditions for bioleaching of uranium from El-Sella mineralisation using A. clavatus are 9 days of incubation, 30°C and agitation speed of 175 rpm. A. clavatus represents an excellent candidate for uranium bioleaching from its ore.
Acknowledgments
This work was jointly supported by Zagazig University and the Nuclear Materials Authority, Cairo, Egypt. We are grateful to the reviewers, Mrs Melanie Porter of Taylor & Francis, Abingdon, and the Editor, Dr Michael Brett-Crowther, for their clarity and patience.
Disclosure statement
No potential conflict of interest was reported by the author.