Long-term performance of a plant microbial fuel cell with Spartina anglica

The plant microbial fuel cell is a sustainable and renewable way of electricity production. The plant is integrated in the anode of the microbial fuel cell which consists of a bed of graphite granules. In the anode, organic compounds deposited by plant roots are oxidized by electrochemically active bacteria. In this research, salt marsh species Spartina anglica generated current for up to 119 days in a plant microbial fuel cell. Maximum power production was 100 mW m−2 geometric anode area, highest reported power output for a plant microbial fuel cell. Cathode overpotential was the main potential loss in the period of oxygen reduction due to slow oxygen reduction kinetics at the cathode. Ferricyanide reduction improved the kinetics at the cathode and increased current generation with a maximum of 254%. In the period of ferricyanide reduction, the main potential loss was transport loss. This research shows potential application of microbial fuel cell technology in salt marshes for bio-energy production with the plant microbial fuel cell

Experimental data: Performance of single carbon granules as perspective for larger scale capacitive bioanodes

The files contain data collected for our publication "Performance of single carbon granules as perspective for larger scale capacitive bioanodes." Authored by Casper Borsje, Dandan Liu, Tom H.J.A Sleutels, Cees J.N. Buisman and Annemiek ter Heijne The use of high surface area electrodes, like carbon-based felt or granules, in Bioelectrochemical Systems is crucial for high volumetric current production. In case activated carbon granules are used, charge can also be stored in the form of an electric double layer in the pores, which has been shown to improve bioanode performance. So far, it is not known how much current can be generated by a single granule. In this study, we investigate the current production and charge storage behavior of a single carbon granule. Two types of activated carbon granules and one graphite granule are tested to find the untapped potential of granular bioanodes. A single activated carbon granule produces up to 0.6 mA, corresponding to 60 mA cm3 granule volume at 300 mV vs. Ag/AgCl anode potential. Charge e discharge experiments show that capacitive granules produced 1.3e2.0 times more charge compared to a graphite granule with low surface area. When extrapolated to other granular systems, our study indicates that the current generated by granular bioanodes can be improved with several orders of magnitude, which could form the basis of an economically feasible Microbial Fuel Cell

(Bio)electrochemical ammonia recovery: progress and perspectives

In recent years, (bio)electrochemical systems (B)ES have emerged as an energy efficient alternative for the recovery of TAN (total ammonia nitrogen, including ammonia and ammonium) from wastewater. In these systems, TAN is removed or concentrated from the wastewater under the influence of an electrical current and transported to the cathode. Subsequently, it can be removed or recovered through stripping, chemisorption, or forward osmosis. A crucial parameter that determines the energy required to recover TAN is the load ratio: the ratio between TAN loading and applied current. For electrochemical TAN recovery, an energy input is required, while in bioelectrochemical recovery, electric energy can be recovered together with TAN. Bioelectrochemical recovery relies on the microbial oxidation of COD for the production of electrons, which drives TAN transport. Here, the state-of-the-art of (bio)electrochemical TAN recovery is described, the performance of (B)ES for TAN recovery is analyzed, the potential of different wastewaters for BES-based TAN recovery is evaluated, the microorganisms found on bioanodes that treat wastewater high in TAN are reported, and the toxic effect of the typical conditions in such systems (e.g., high pH, TAN, and salt concentrations) are described. For future application, toxicity effects for electrochemically active bacteria need better understanding, and the technologies need to be demonstrated on larger scale.This study was funded by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement no. 665874.info:eu-repo/semantics/publishedVersio

Ephrin-B2 reverse signaling regulates progression and lymph node metastasis of oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) is a common malignant tumor of the head and neck and frequently metastasizes to cervical lymph nodes. Aggressive local invasion and metastasis of OSCC are significant factors for poor prognosis. In this study, we investigated whether ephrin-B2 expressed in OSCC contributed to tumor progression and lymph node metastasis. Clinical specimens from patients with OSCC had robust ephrin-B2-positive tumor cells and ephrin-B2 protein level was associated with clinical stage, lymph node metastasis, and poor survival outcomes. We also determined that ephrin-B2 protein level was increased in OSCC cell lines compared to normal human oral keratinocytes and that its levels were associated with the migratory and invasive potential of OSCC cell lines. Transfection of an EFNB2-specific small interfering RNA (siRNA) into SAS-L1 cells significantly reduced proliferation, attachment, migration, and invasion through phosphorylation of the epidermal growth factor receptor, FAK, ERK1/2, p38, AKT, and JNK1/2 pathways. Furthermore, knockdown of EFNB2 significantly suppressed adhesion and transmigration of SAS-L1 cells toward human lymphatic endothelial cells. In addition, the growth rate of tumor xenografts and cervical lymph node metastases of OSCC were suppressed by local injection of EFNB2 siRNA. These results suggest that ephrin-B2 overexpression and activation of the ephrin-B2 reverse signaling pathway in tumor microenvironment in OSCC facilitates progression and lymph node metastasis via enhancement of malignant potential and interaction with surrounding cells

Decoupling hydrogen and oxygen evolution during electrolytic water splitting using an electron-coupled-proton buffer

Hydrogen is essential to several key industrial processes and could play a major role as an energy carrier in a future ‘hydrogen economy’. Although the majority of the world's hydrogen supply currently comes from the reformation of fossil fuels, its generation from water using renewables-generated power could provide a hydrogen source without increasing atmospheric CO2 levels. Conventional water electrolysis produces H2 and O2 simultaneously, such that these gases must be generated in separate spaces to prevent their mixing. Herein, using the polyoxometalate H3PMo12O40, we introduce the concept of the electron-coupled-proton buffer (ECPB), whereby O2 and H2 can be produced at separate times during water electrolysis. This could have advantages in preventing gas mixing in the headspaces of high-pressure electrolysis cells, with implications for safety and electrolyser degradation. Furthermore, we demonstrate that temporally separated O2 and H2 production allows greater flexibility regarding the membranes and electrodes that can be used in water-splitting cells