Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1186/s13068-017-0994-7
Title (Primary) Enhancing methane production from food waste fermentate using biochar: the added value of electrochemical testing in pre‑selecting the most effective type of biochar
Author Cruz Viggi, C.; Simonetti, S.; Palma, E.; Pagliaccia, P.; Braguglia, C.; Fazi, S.; Baronti, S.; Assunta Navarra, M.; Pettiti, I.; Koch, C.; Harnisch, F. ORCID logo ; Aulenta, F.
Source Titel Biotechnology for Biofuels
Year 2017
Department UMB
Volume 10
Page From art. 303
Language englisch
Supplements https://static-content.springer.com/esm/art%3A10.1186%2Fs13068-017-0994-7/MediaObjects/13068_2017_994_MOESM1_ESM.docx
Keywords Anaerobic digestion; Biochar; Direct interspecies electron transfer (DIET); Electron-donating capacity (EDC); Food wasteMethane
UFZ wide themes RU4;
Abstract

Background

Recent studies have suggested that addition of electrically conductive biochar particles is an effective strategy to improve the methanogenic conversion of waste organic substrates, by promoting syntrophic associations between acetogenic and methanogenic organisms based on interspecies electron transfer processes. However, the underlying fundamentals of the process are still largely speculative and, therefore, a priori identification, screening, and even design of suitable biochar materials for a given biotechnological process are not yet possible.

Results

Here, three charcoal-like products (i.e., biochars) obtained from the pyrolysis of different lignocellulosic materials, (i.e., wheat bran pellets, coppiced woodlands, and orchard pruning) were tested for their capacity to enhance methane production from a food waste fermentate. In all biochar-supplemented (25 g/L) batch experiments, the complete methanogenic conversion of fermentate volatile fatty acids proceeded at a rate that was up to 5 times higher than that observed in the unamended (or sand-supplemented) controls. Fluorescent in situ hybridization analysis coupled with confocal laser scanning microscopy revealed an intimate association between archaea and bacteria around the biochar particles and provided a clear indication that biochar also shaped the composition of the microbial consortium. Based on the application of a suite of physico-chemical and electrochemical characterization techniques, we demonstrated that the positive effect of biochar is directly related to the electron-donating capacity (EDC) of the material, but is independent of its bulk electrical conductivity and specific surface area. The latter properties were all previously hypothesized to play a major role in the biochar-mediated interspecies electron transfer process in methanogenic consortia.

Conclusions

Collectively, these results of this study suggest that for biochar addition in anaerobic digester operation, the screening and identification of the most suitable biochar material should be based on EDC determination, via simple electrochemical tests.

Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=19711
Cruz Viggi, C., Simonetti, S., Palma, E., Pagliaccia, P., Braguglia, C., Fazi, S., Baronti, S., Assunta Navarra, M., Pettiti, I., Koch, C., Harnisch, F., Aulenta, F. (2017):
Enhancing methane production from food waste fermentate using biochar: the added value of electrochemical testing in pre‑selecting the most effective type of biochar
Biotechnol. Biofuels 10 , art. 303 10.1186/s13068-017-0994-7