Microbial recovery of rhodium from dilute solutions by the metal ion–reducing bacterium Shewanella algae

• A novel method is proposed for rhodium(III) recovery from dilute solutions.
• Rhodium nanoparticles are deposited intracellularly in Shewanella algae.
• Bioreductive recovery is achieved within 60 min at pH 7 and 25 °C.
• This is the first demonstration of bioreductive recovery of rhodium.

An environmentally friendly method using the metal ion-reducing bacterium Shewanella algae was developed to recover soluble Rh(III) from dilute solutions. Rhodium nanoparticles were deposited intracellularly in S. algae. Resting cells of S. algae were able to reduce aqueous Rh(III) to metallic Rh(0) at room temperature and neutral pH within 60 min, using lactate as the electron donor.