Truls Norby is a professor at the Department of Chemistry at the Faculty of Mathematics and Natural Sciences at the University of Oslo and Head of the research Group for electrochemistry working on solid state electrochemistry. Photo: Angelique Culvin Riccot , Oslo Science Park.
Read about Norby's research and innovation project
Nitrogen fertilisers are critical to global food supply. According to Truls Norby, the challenge of today’s production is the enormous CO2 emissions that come with the use of natural gas as the source of the hydrogen that is used to make ammonia as an intermediate.
– We need to find efficient ways of using renewable energy and to make the fertilisers locally at smaller scale, says Norby.
Norby further explains that there is a direct and indirect method to produce fertilisers. The indirect method that is widely used now, goes via the production of ammonia (NH3) and is known as the Haber-Bosch process. The most common source of the hydrogen component (H2) of ammonia comes from natural gas which produces considerable amounts of carbon emissions. The other component on the other hand, nitrogen (N2) comes from air. This process of making fertilisers via ammonia has been considered to be more efficient as opposed to the direct method involving the fixation of nitrogen. This direct method on the other hand is known as the Birkeland-Eyde method involving the reaction of nitrogen (N2) with oxygen (O2) to make nitrogen oxides (NOx).
Development of a new way of producing fertilisers
Norby and his team have been involved in optimizing the production process of ammonia for the further reaction with oxygen to make these nitrogen oxides.
– Our collaboration with a Japanese group has led us to discover that there is a special way to conduct electrical current through a porous material. This material acts as a catalyst for the production of ammonia and makes the reaction more efficient, says Norby.
Further development of this new method aimed to find different ways of making fertilisers through the binding of nitrogen to different materials. This has led to the possible and unexpected discovery of a more efficient method of fixing nitrogen using a plasma – plasma is considered the 4th state of matter which is normally superheated causing the electrons to detach from the atoms forming an ionized gas.
– Through this optimization process, we discovered a new method for fixing nitrogen at a colder temperature of plasma. This appears to be different than the plasma version that is in the Birkeland-Eyde method where the plasma used was at very high temperatures and in a gas atmosphere. Our plasma works at room temperature and is located inside a porous powder, explains Norby.
The new plasma method was found to work well in fixing nitrogen and oxygen from the air and producing nitrogen oxides. Despite the method not being entirely novel, the combination with the porous catalyst has increased the knowledge capacity of Norby and his team about the plasma.
– To make nitrogen oxides directly from air and electricity is a kind of a holy grail. This not only circumvents the making of ammonia but also makes it possible to use renewable energy as an energy source. There are several people working on this but during just this one year, we have learned a lot about plasma and several ways of operating it, explains Norby.
At this point of time, they are not able to make nitrogen oxides at a more efficient level than the current top competitors, but Norby thinks the progress is promising and has gathered attention from some industries.
– We have not had enough resources to push the limit beyond running the system at a smaller scale and under milder conditions. However, we can see that the production and the efficiency are in line with the increase in current. We have not had enough power supplies including safety precautions to run high enough currents as it involves several kilovolts of voltage. Proper and safe lab reactors would need to be installed to really push the limits, comments Norby.
Smaller and modular scale production of fertilisers
According to Norby, modular systems for the production of fertilisers are needed especially in third world countries to make it possible to produce emission-free fertilisers locally at a smaller scale. Currently, farmers are dependent on large companies to buy nitrogen-enriched fertilisers. Further development of the plasma method may potentially allow the possibility that farmers themselves can install his smaller scale fertilizer producing system and thus being less dependent on external fertilizer supply and more self-sufficient, says Norby.
The need for and use of nitrogen is demonstrated in Norby’s group using hydroponic lettuce – hydroponic is a horticulture technique of cultivating plants without soil from the earth. Lettuce that has been grown with nitrogen are noticeable fresher looking compared to ones without a supply of nitrogen.
– We like to demonstrate the results of our idea through a type of proof-of-concept experiment by growing plants with nitrogen-free fertilisers and using our small-sized generator of nitrogen. We have done some small initial tests and the aim is to visibly demonstrate that our small reactors are making the nitrogen that the plants need, says Norby.
These experiments serve as a rather simple representation of what Norby hopes to achieve in the near future where there are more efficient processes that exist at different scales and the third world countries will be able to implement them independently.
Read about Norby's experience with innovation at the UiO and the UiO Growth House
The innovation process takes time
There are multiple steps of varying levels of scope in the innovation process of any project. Passing every level requires funding that drives the process of upscaling and validation.
– Innovation takes time. One has to be patient and steadfast. Besides the research process there are also additional challenges where funding seems to be in favour of the life sciences, pharmaceuticals and biology but less towards physics and chemistry, says Norby.
According to Norby innovation is one of the legs a university should stand on today. However, the innovation environment at the University of Oslo is still not as developed yet as the other traditional legs of science and teaching. Funding is critical for every step towards commercialisation and progress in a project varies according to the different fields of research.
– Starting an IT company of 2 or 3 people, costs next to nothing when compared to material science and energy technology where you need more funding and a lot more equipment in comparison to the IT company. Funding support from units like the UiO Growth House is very useful and UiO Growth House is probably able to help a new entrepreneur to startup something, explains Norby.
Norby and his team has received seed funding from the UiO Growth House in 2023 to work on exploring the fixation of nitrogen using the cold plasma method.