Biotransformation of plutonium

Onuki, Toshihiko; Francis, A. J.*

We have studied the interaction of Pu with microorganisms. Pu as Pu(6) is preferably sorbed to bacterial cells in the mixture of Bacillus subtilis and kaolinite, and that Pu(6) is reduced to Pu(5) and then to Pu(4) during the interaction with the mixture. Study on reduction of Pu(4) in the presence of citric acid at pH 7.0 suggested that Pu(4) is reduced to Pu(3) by the activity of sulphate reducing bacteria. These facts indicate that microorganisms change chemical states of Pu during migration in environments.