UNSW authors say that ammonia synthesis was one of the critical achievements of the 20th century
Chemical engineers at The University of New South Wales (UNSW), Sydney, have recently found a way to make ’green’ ammonia from the air, water, and renewable electricity that does not require the high temperatures, high pressure and huge infrastructure currently needed to produce this essential compound.
In a paper published in Energy and Environmental Science, the authors from UNSW and the University of Sydney say that ammonia synthesis was one of the critical achievements of the 20th century. When used in fertilizers that quadrupled the output of food crops, it enabled agriculture to sustain an ever-expanding global population.
But since the beginning of the 1900s when it was first manufactured on a large scale, the production of ammonia has been energy intensive – requiring temperatures higher than 400oC and pressures greater than 200atm – and all powered by fossil fuels.
Dr Emma Lovell, a co-author on the paper from UNSW’s School of Chemical Engineering, says the traditional way to make ammonia – known as the Haber-Bosch process – is only cost-effective when produced on a massive scale due to the huge amounts of energy and expensive materials required.
“The current way we make ammonia via the Haber-Bosch method produces more CO2 than any other chemical-making reaction,” she says.
