Making Ammonia Greener

Engineers create the chemical from nitrogen and water

Headshot of Case Western Reserve chemical engineer Julie Renner Julie Renner

Ammonia, a compound first synthesized on a commercial scale about a century ago, has dozens of modern uses and is essential in making the fertilizer that now sustains most of our global food production.

But it's mainly been produced in hulking chemical plants requiring large amounts of hydrogen gas from fossil fuelsmaking ammonia among the most energy-intensive of all large-volume chemicals, said Julie Renner, PhD, a chemical engineer at Case Western Reserve.

Headshot of Case Western Reserve chemical engineer Mohan Sankaran Mohan Sankaran

Now Renner and colleague Mohan Sankaran, PhD, are working to change that by combining their know-how. Her expertise is in electrochemical synthesis; his in the applications of plasmas.

They have developed a way to create ammonia from nitrogen and water at low temperature and low pressure. They've done it successfully so far in small batches and in a laboratory without using hydrogen or the solid metal catalyst necessary in traditional processes. Their aim: to develop a process that could someday lead to smaller, more localized ammonia plants that use green energy.

"Our approachan electrolytic process with a plasmais completely new," said Sankaran, the Goodrich Professor of Engineering Innovation.

Plasmas, often referred to as the fourth state of matter (apart from solid, liquid or gas), are ionized clouds of gas.

And because the new process doesn't need high pressure, high temperature or hydrogen, it is scal-ablespan>"the ideal kind of technology for a much smaller plant, one with high potential to be powered by renewable energy," said Renner, a Climo Assistant Professor.

The results of their collaboration were published earlier this year in the journal Science Advances.

— Mike Scott