Researchers from the University of Adelaide in Australia have developed a new strategy for producing hydrazine from urea, using electricity and sodium chloride. The compound is used in several industries, including pharmaceutical and aerospace, and also has emerging applications in energy systems and electric vehicle batteries.
The method, developed by a team from the School of Chemical Engineering at the University of Adelaide, could represent a more sustainable alternative to conventional hydrazine production processes, which rely on other hazardous chemicals and require large amounts of energy.
“Hydrazine is industrially synthesized from ammonia or from a urea-derived product produced via an established method,” explains the study’s principal author, Pengtang Wang.
“These methods have been developed and used for decades, but they rely on other hazardous chemicals and consume a lot of energy, which makes them costly and environmentally challenging,” he adds.
The research, published in the scientific journal Nature Synthesis, is based on an electrochemical process that converts urea into hydrazine through the use of electricity and sodium chloride.
“Urea was chosen as the feedstock because it is abundant in human urine,” explains Wang. “Converting this readily available resource into hydrazine could constitute a potential route for fuel production, including applications in fuel cells and long-duration space missions.”
According to the researchers, sodium chloride plays a fundamental role in the reaction by generating chlorine species adsorbed on the electrode surface. These species react with urea, forming N-chlorourea, which is subsequently converted into hydrazine through a simple hydrolysis process.
The team managed to achieve high-yield hydrazine production and demonstrated that the process can operate with different sources of urea, including pure urea, urea-rich wastewater, and human urine.
Despite the promising results, the researchers acknowledge that there are still obstacles before the technology can be applied at an industrial scale.
“Although this electrochemical strategy enables efficient conversion of urea to hydrazine, practical engineering challenges and cost-related obstacles remain, including salt buildup and the energy required to isolate the product,” says Wang.
Future work should focus on reducing costs, simplifying product separation, improving the continuous operation of the systems, and developing reactors more suitable for practical application.
“With these engineering advances, we believe this technology could provide a sustainable alternative for the production of hydrazine, powered by electricity from renewable sources,” concludes the researcher.
