Monash University researchers, together with national water utility companies, are looking at ways to produce hydrogen energy more sustainably through repurposing wastewater.

The Sustainable Hydrogen Production from Used Water project, which recently received an ARC Linkage grant, aims to address the challenge of water scarcity in the process of hydrogen production by developing an innovative approach that repurposes wastewater as the feed for hydrogen production through water electrolysis - the process of using electricity to split water into hydrogen and oxygen.

The group of researchers, Professor Xiwang Zhang, Professor Huanting Wang and Dr Yinlong Zhu, from the Department of Chemical Engineering at Monash University will look to advance the practical applications of water electrolysis for scalable and sustainable hydrogen production and help Australia secure a leading position in the global emerging hydrogen economy.

Chemical Engineering Professor and Director of the ARC Research Hub for Energy-efficient Separation, Xiwang Zhang, said the project presents an opportunity to minimize freshwater consumption and use the large amounts of wastewater generated in Australia’s major capital cities.

"The amount of wastewater currently available for use is far more than the amount of water required in water electrolysis for hydrogen production. Most of the treated water throughout Australia is currently discharged to surrounding water bodies or recycled for irrigation after being treated in centralized municipal wastewater treatment plants. Given the volume of the treated water from these plants is highly consistent, it is a promising water source for water electrolysis," said Zhang.

The project will be working closely with national water utility companies Southeast Water, Melbourne Water, Yarra Valley Water and Water Corporation, through Water Research Australia (WaterRA).

Dr. Arash Zamyadi from WaterRA is the Partner Investigator and said although the majority of pollutants in wastewater have been effectively removed in the current wastewater treatment processes, small amounts of impurities (residual organics and ions) remain.

"There still remains a knowledge gap in how the impurities affect water electrolyzer design and process operation. Through this research, we hope to develop an in-depth understanding of the impacts of water impurities in used water on the performance and durability of water electrolysers, and subsequently develop guidelines for the design of highly durable water electrolysers and the operation and upgrade of existing wastewater treatment plants," said Zamyadi.

The findings from this project have the capability to contribute to the global hydrogen export market. With demand for hydrogen exported from Australia alone tipped to be over 3 MMt each year by 2040, resulting in up to $10 B each year for the Australian economy.