NWO-xs grant for new ‘Green’ way to produce Ammonia

‘Holy grail’ in chemistry

“The currently-used Haber-Bosch process is a very old way of making ammonia and it’s very polluting,” says Ramdin, “It’s also energy intensive because everything has to be done at very high temperatures and pressures. So looking for an alternative technique that can compete with the Haber-Bosch process is considered to be the ‘holy grail’ in chemistry.”

One way to reduce CO2 emissions is to choose renewable sources of the hydrogen used in the reaction for making ammonia – a much more environmental friendly method than the Steam Methane Reforming (SMR) method currently used.

Reactions at room temperature

But crucially, Ramdin’s idea is to replace the one-step process of combining hydrogen and nitrogen at high temperatures and pressures by a series of reactions using lithium: “The first step is to react solid lithium with nitrogen gas to produce lithium nitride. The second step is to react lithium nitride with water vapour to produce ammonia and lithium hydroxide. And this can all take place at room temperature and pressure so it’s a lot less energy intensive.”

Capture of atmospheric carbon dioxide

Ramdin also has plans for the lithium hydroxide produced in the second stage reaction: “We can use it to capture carbon dioxide from the atmosphere or any point source which will produce lithium carbonate – and this is interesting because we use lithium carbonate in lithium batteries – so in theory can sell this lithium carbonate to lithium battery producers.”

Eliminating side-reactions

Starting on 1st March 2023, this one-year Green Ammonia Production using Lithium (Li) Chemistry project (GAPLiC) aims to use the € 50,000 from the NWO-xs grant to build a small lab-scale set up to perform all these reactions – and eliminating the side-reactions is a priority: “Lithium is very reactive so if there’s oxygen or other impurities present, lithium will form by-products such as lithium oxide. So the challenge is to eliminate these side reactions.”