Author(s): Rocha, Ana Catarina ; Braga, Cátia Sofia Neves ; Oliveira, Inês ; Soares, O. Salomé G. ; Pereira, M. Fernando R. ; Pereira, Luciana ; Salvador, Andreia Filipa Ferreira ; Martins, Gilberto
Date: 2023
Persistent ID: https://hdl.handle.net/1822/88821
Origin: RepositóriUM - Universidade do Minho
Project/scholarship: info:eu-repo/grantAgreement/FCT/3599-PPCDT/PTDC%2FBTA-BTA%2F2249%2F2021/PT;
Subject(s): Anaerobic Digestion; Conductive nanomaterials; Methane production
The search for renewable energy sources is one of the top priorities of humanity. Biomethane production through anaerobic digestion (AD) could help to reduce the dependence on fossil energy. The addition of conductive nanomaterials (CM) to AD systems results in the acceleration of methane production (MP) and in the improvement of the resilience of these systems. However, the mechanisms underlying this phenomenon are still unclear, particularly regarding the effects of materials on the activity of methanogens. The present work aimed to evaluate the effect of adding different carbon nanomaterials to a hydrogenotrophic and an acetoclastic culture. For this purpose, experiments were conducted with pure cultures of Methanobacterium formicicum and Methanosaeta harundinacea, in the presence and absence of 0.5 g/L of activated carbon (AC), carbon nanotubes (CNT), carbon black, graphite, and graphene. The experiments were conducted under strictly anaerobic conditions, and MP was monitored over time. In the assay with M. formicicum, the lag phase was shorter in all conditions with the presence of CM, compared to the control without CM. The initial MP rates reached values 11.6x, 9.4x, 6.4x, 6.3x, 5.3x, 3.0x and 2.1x higher than the control, with AC_300-500µm, AC_100-300µm, carbon black, AC_<100µm, graphite, graphene and CNT, respectively. Regarding the assay with M. harundinacea, the lag phases were also reduced with all the CM tested, and the MP rates were higher than the control in the presence of graphite and glassy carbon. In the presence of the other CM, the MP rate was also higher than the control, but in less extent. In conclusion, the presence of CM had a positive influence on both MP rates and the duration of the lag phase, and time of incubation.
Portuguese Foundation for Science and Technology (FCT) under the scope of the CM4Methane project (Ref: PTDC/BTA-BTA/2249/2021; https://doi.org/10.54499/PTDC/BTA-BTA/2249/2021)
info:eu-repo/semantics/publishedVersion
