Format

Send to

Choose Destination
Waste Manag. 2017 Oct;68:165-172. doi: 10.1016/j.wasman.2017.07.025. Epub 2017 Jul 23.

Effects of an applied voltage on direct interspecies electron transfer via conductive materials for methane production.

Author information

1
School of Civil, Environmental and Architectural Engineering, Korea University, Seoul, South Korea.
2
School of Civil, Environmental and Architectural Engineering, Korea University, Seoul, South Korea; KU-KIST Green School, Graduate School of Energy and Environment, Korea University, Seoul, South Korea. Electronic address: heedeung@korea.ac.kr.

Abstract

Direct interspecies electron transfer (DIET) between exoelectrogenic bacteria and methanogenic archaea via conductive materials is reported as an efficient method to produce methane in anaerobic organic waste digestion. A voltage can be applied to the conductive materials to accelerate the DIET between two groups of microorganisms to produce methane. To evaluate this hypothesis, two sets of anaerobic serum bottles with and without applied voltage were used with a pair of graphite rods as conductive materials to facilitate DIET. Initially, the methane production rate was similar between the two sets of serum bottles, and later the serum bottles with an applied voltage of 0.39V showed a 168% higher methane production rate than serum bottles without an applied voltage. In cyclic voltammograms, the characteristic redox peaks for hydrogen and acetate oxidation were identified in the serum bottles with an applied voltage. In the microbial community analyses, hydrogenotrophic methanogens (e.g. Methanobacterium) were observed to be abundant in serum bottles with an applied voltage, while methanogens utilizing carbon dioxide (e.g., Methanosaeta and Methanosarcina) were dominant in serum bottles without an applied voltage. Taken together, the applied voltage on conductive materials might not be effective to promote DIET in methane production. Instead, it appeared to generate a condition for hydrogenotrophic methanogenesis.

KEYWORDS:

Anaerobic digestion; Direct interspecies electron transfer; Methanobacterium; Methanogenesis; Methanosaeta

PMID:
28743578
DOI:
10.1016/j.wasman.2017.07.025
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center