Bubble Column
Original Published Date: 
Friday, January 22, 2021

Full article issued by The University of Sydney.

ARC-supported researchers have discovered a greener way to produce ammonia, one of the world’s most important chemicals that supports global food supply, and is a possible storage solution for the hydrogen energy industry.

Currently, the production of ammonia is incredibly energy-intensive, accounting for roughly two per cent of global energy consumption. It is also highly eco-destructive, comprising 1.4 per cent of total global CO2 emissions.

A collaborative effort between researchers at The University of Sydney and the University of New South Wales (UNSW) has found a way to make ammonia production 'green', using only air, water and renewable energy sources such as solar.

Combining atmospheric plasma, the fourth state of matter, with electrochemistry – a field of chemistry that uses electricity to influence a chemical change – the researchers used a bubble column to break down nitrogen, creating reactive water which was then processed in a second electrochemistry reactor.

Leading the UNSW team, Scientia Professor Rose Amal, co-director of the ARC Training Centre for Global Hydrogen Economy, said that the team’s green method of ammonia production could solve the problem of storage and transport of hydrogen energy.

'Hydrogen is very light, so you need a lot of space to store it, otherwise you have to compress or liquify it,' she said. 'But liquid ammonia actually stores more hydrogen than liquid hydrogen itself. And so there has been increasing interest in the use of ammonia as a potential energy vector for a carbon-free economy.'

The plasma technology supporting this research has already been successfully spun-out by PlasmaLeap Technologies, which is based at the Sydney Knowledge Hub, The University of Sydney’s technology startup incubator.

Photo credit: 

The researchers used a bubble column to break down nitrogen, creating reactive water which was then processed in a second electrochemistry reactor. Credit: Professor Patrick 'PJ' Cullen.