Electrochemical Bioremediation of Uranium VI Using Geobacter Sulfurreducens on Boron-Doped Diamond Electrode Surface

Abstract

The development of nuclear science and technology has led to increasing nuclear waste containing uranium. The contamination associated with nuclear activity, especially uranium, is a significant concern for human and environmental health. Due to the high toxicity, radioactivity, and extensive half-life of uranium, it is necessary to find a way to remove it from the environment. One alternative to solve this problem is bioremediation. With this technique, microorganisms can be used to reduce, eliminate, contain, or transform hazardous waste like radionuclides. This research proposes using the bacteria Geobacter sulfurreducens to reduce uranium (VI) (U(VI)) to uranium (IV) (U(IV)). The experiment consists in the G. sulfurreducens' immobilization using the boron-doped diamond electrodes (BDD) as an electron donor by electrochemical processes. Taking advantage of the bacteria's microbial metabolism process and using U (VI) as an electron acceptor will reduce the ion to U (IV). First, a potential of -500mV (vs. Ag/AgCl) will be applied to immobilize the G. sulfurreducens’ to the BDD electrode surface. Second, with the application of a potential between -500mV to -700mV (vs. Ag/AgCl), it will expect to reduce the uranium ion and remove it from the media. Preliminary studies of the behavior of BDD electrodes in the presence of U(VI) had been carried out to determine the electrochemical conditions at which the substrate works with this ion. The results found with these studies will show how G. sulfurreducens’ will improve U(VI) bioremediation through electrochemical processes.This research has the financial support from the DOE- Minority Serving Institutions Partnership Program, National Nuclear Security Administration, "Scholarly Partnership in Nuclear Security (SPINS)", Grant Number DE NA0003980. Figure 1