Bioelectrochemical metal remediation and recovery of Au3+, Co2+ and Fe3+ metal ions

Abstract

Bioelectrochemical metal remediation and recovery of Au 3+ , Co 2+ and Fe 3+ metal ions.

Behavior of metal ions in bioelectrochemical systems: A review

“…Varia et al explored the influences of S. putrefaciens CN32 on electroreduction and electrodeposition of gold, cobalt and iron ions dissolved in aqueous, which proved that these metal species were biosorbed and utilized by electroactive gram negative bacteria as electron acceptors as part of metabolic respiration under anoxic conditions. Moreover, the related enzymes and endogenous electron mediators contributed to the changes of electron transfer reaction thermodynamics, especially for gold systems [194]. By means of enzyme electrochemical system, gold nanoparticles could be locally deposited on Pd substrates through direct and mediated electron transfer by cellobiose dehydrogenase that consisted of two electron transfer mediate domains [195].…”

Microbial electrolysis cells with biocathodes and driven by microbial fuel cells for simultaneous enhanced Co(II) and Cu(II) removal

“…A lower reductive peak current on the biotic cathodes, however, suggested some degree of mass transfer inhibition due to the bacterial attachment to the electrode surface [27]. Other researchers also observed similar results, where biotic cathodes for hydrogen evolution and Au(III) or Co (II) recovery had lower reductive peak currents than abiotic cathodes despite the biotic cathodes having more positive potentials [27,28]. In addition, current density based on only the biofilm-covered area (which can only roughly estimated by microscopic examination) was recently suggested as a relatively good method for assessing BES performance, particularly for electrodes of porous graphite felt as used here [29].…”

“…2(c)). A more positive reductive potential on the biotic electrodes indicated a decrease in the overall free energy of the electron transfer reaction, mainly due to bacterial and bacterial component interactions with the electrode surface, which would decrease the energy required for Co(II) removal [27]. A lower reductive peak current on the biotic cathodes, however, suggested some degree of mass transfer inhibition due to the bacterial attachment to the electrode surface [27].…”

“…A more positive reductive potential on the biotic electrodes indicated a decrease in the overall free energy of the electron transfer reaction, mainly due to bacterial and bacterial component interactions with the electrode surface, which would decrease the energy required for Co(II) removal [27]. A lower reductive peak current on the biotic cathodes, however, suggested some degree of mass transfer inhibition due to the bacterial attachment to the electrode surface [27]. Other researchers also observed similar results, where biotic cathodes for hydrogen evolution and Au(III) or Co (II) recovery had lower reductive peak currents than abiotic cathodes despite the biotic cathodes having more positive potentials [27,28].…”

The potentional of plants to cleanup metals from an old landfill site

“…These heavy metals have an excellent potential to transfer to the ecological system and the food chain [1,2]. Different methods have been used for the remediation of metals from soils like extraction with chelating agents (EDTA or other biodegradable agents) [3], sequential acid leaching [4], washing [5], hydrometallurgy technique [6], Bioelectrochemistry [7] and phytoremediation [8].…”