Researchers Jason He, the Laura and William Jens Professor of Energy, Environmental and Chemical Engineering at Washington University in St. Louis have developed a method to significantly increase the production of short-chain volatile fatty acids (VFAs) from sewage sludge. This advancement could enhance the efficiency of wastewater treatment processes and provide a valuable resource for various industrial applications.
Sun, J., & He, Z. (2025). Light stimulated H2O2 inhibition on methanogenesis during anaerobic digestion towards enhanced VFAs production. Water Research, 286, 124229. https://doi.org/10.1016/j.watres.2025.124229
The team’s approach involves using hydrogen peroxide (H₂O₂) to inhibit methanogenesis; the process by which microorganisms convert organic matter into methane; and promote the accumulation of VFAs. In laboratory experiments, reactors treated with H₂O₂ produced over 30 times more VFAs than untreated controls. This suggests that H₂O₂ can effectively redirect the metabolic pathways in anaerobic digestion toward VFA production.
Jason He from Washington University in St. Louis stated,
“Can we recover something potentially of higher value than biogas?” With light, the hydrogen peroxide dosage can be greatly reduced”.
A notable discovery occurred when Ph.D. student Jiasi Sun observed that reactors exposed to light produced higher VFA concentrations. This led to the realization that light accelerates the breakdown of H₂O₂ into reactive oxygen species, further inhibiting methanogenesis. As a result, researchers are exploring the integration of LED lighting into reactor designs to enhance VFA yields and reduce H₂O₂ usage.
The potential applications of this technology are significant. VFAs are valuable intermediates in the production of bioplastics, pharmaceuticals, and other chemicals. By converting sewage sludge into these valuable compounds, wastewater treatment facilities could offset operational costs and contribute to a circular economy.
This research represents a promising step toward more sustainable and resource-efficient wastewater treatment practices. The integration of light and hydrogen peroxide in anaerobic digestion processes could pave the way for innovative solutions in environmental engineering and resource recovery.
Adrian graduated with a Masters Degree (1st Class Honours) in Chemical Engineering from Chester University along with Harris. His master’s research aimed to develop a standardadised clean water oxygenation transfer procedure to test bubble diffusers that are currently used in the wastewater industry commercial market. He has also undergone placments in both US and China primarely focused within the R&D department and is an associate member of the Institute of Chemical Engineers (IChemE).
