Effects of Applied Potential and Reactants to Hydrogen-Producing Biocathode in a Microbial Electrolysis Cell.
Swee Su Lim, Byung Hong Kim, Da Li, Yujie Feng, Wan Ramli Wan Daud, Keith Scott, Eileen Hao Yu · Frontiers in chemistry · 2018
Research-use notice
Independent study record
Each H2HUBB study page organizes source-linked research details for educational use. Interpretation should remain proportional to the study design, population, controls, and limitations.
H2HUBB TAKEAWAY
In Double-chamber electrochemical cells, 25 cm 3 (mL) in volume (each chamber) were used as described in Lim et al. ( 2017 ), hydrogen recycle rate was reduced and then increased in between 5.05 and 26.86 mL/min after 8 days of enrichment to check whether the bioelectrode was actively growth under hydrogen as electron donor. The authors concluded that organic carbons were found in the cathode effluents, suggesting that microbial interactions probably happen between acetogens and sulfate reducing bacteria (SRB). These findings from a laboratory model add evidence about molecular hydrogen's biological effects in the model studied.
What the Findings Mean
H2HUBB reviewed how molecular hydrogen affected the outcomes measured in Double-chamber electrochemical cells, 25 cm 3 (mL) in volume (each chamber) were used as described in Lim et al. ( 2017 ). Hydrogen recycle rate was reduced and then increased in between 5.05 and 26.86 mL/min after 8 days of enrichment to check whether the bioelectrode was actively growth under hydrogen as electron donor.
What the Researchers Studied
The researchers studied Double-chamber electrochemical cells, 25 cm 3 (mL) in volume (each chamber) were used as described in Lim et al. ( 2017 ). The study used a in vitro cell-culture laboratory experiment.
What Effects Did Molecular Hydrogen Have?
The enrichment of hydrogen-producing biocathode was performed as stated in Rozendal et al. ( 2008 ). Once a stable current was observed, the biocathode potential was further increased and fixed at −1.0 V versus standard hydrogen electrode (SHE) for all the experiments unless stated otherwise. During the enrichment process, hydrogen was filled in cathode headspace and recycled by a peristaltic pump into the cathode chamber and then bubbled through the catholyte. Hydrogen recycle rate was reduced and then increased in between 5.05 and 26.86 mL/min after 8 days of enrichment to check whether the bioelectrode was actively growth under hydrogen as electron donor. The authors concluded that organic carbons were found in the cathode effluents, suggesting that microbial interactions probably happen between acetogens and sulfate reducing bacteria (SRB). Understanding the mechanism of electron transfer between the cathode and microorganisms in cathode biofilms in microbial electrolysis cells (MECs) for hydrogen production is important.
Why These Findings Matter
This publication adds useful evidence about where molecular hydrogen did and did not change the measured outcomes, helping define the larger therapeutic evidence base.
How Strong Is This Evidence?
This is laboratory evidence from a in vitro cell-culture laboratory experiment. It is most informative for the biological mechanisms, cellular responses, or biochemical outcomes directly measured.
Technical Study Details
H2HUBB classifies this publication as laboratory study with laboratory or cellular evidence. The research population or model was Double-chamber electrochemical cells, 25 cm 3 (mL) in volume (each chamber) were used as described in Lim et al. ( 2017 ). The study used a in vitro cell-culture laboratory experiment.
Limitations and Safety
Reported limitations: The sulfate reduction in this case was limited by low sulfate concertation (<288 mg SO 4 2 – /L). Four flow rates were used to test the mass transport limitation: 0, 2.8, 7.1, and 11.4 mL/min.
Original Study and H2HUBB Research Context
H2HUBB presents this source-grounded research record as one contribution to the broader molecular-hydrogen evidence base.