Dynamic uranium enrichment and pH regulation in uranium solution by Deinococcus radiodurans

Abstract

Uranium enrichment by Deinococcus radiodurans under different times, bacterial doses, initial uranium concentrations, solution pH values, and pH-adjusted uranium solutions was explored, and the enrichment mechanism was elucidated by Fourier transmission infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The optimal conditions for adsorption included an enrichment time of 60 min, bacterial dose (i.e., the volume of bacterial liquid corresponding to an OD600 of 1) of 10 mL, initial uranium concentration of 30 mg/L, and solution pH of 5.0. The solution pH increased slightly after enrichment with uranium solutions of different pH. FTIR and SEM analyses revealed several changes in active functional groups and bacterial characteristics before and after enrichment. Deinococcus radiodurans has good enrichment performance for low uranium solution, and it regulated the pH of the uranium solution and increased the pH of the adsorbed uranium solution.

Keywords

• deinococcus radiodurans
• uranium
• enrichment
• ph regulation