Inert nitrogen forced to react with itself
Imitating nature, humans use the all-important Haber-Bosch process to break down nitrogen into ammonia, which can then be further processed to produce fertilizers and to make nitrogen available for the production of pigments, fuels, materials, pharmaceuticals and beyond. The production of compounds that contain chains of two, three or four nitrogen atoms -- which are notably of pharmaceutical importance in vaso-dilating drugs, for example -- requires the reassembly of mono-nitrogen molecules such as ammonia, because no direct reaction exists that can directly connect molecules of dinitrogen.
This week, research teams from Germany, from Julius-Maximilians-Universität Würzburg (JMU) and Goethe University in Frankfurt, report a completely new chemical reaction in Science magazine. The new process uses boron-containing molecules to directly couple two molecules of N2 into a N4 chain. For the first time, they have succeeded in directly coupling two molecules of atmospheric nitrogen N2 with each other without first having to split the dinitrogen into ammonia, thus bypassing the Haber-Bosch process. This new method could enable the direct generation of longer nitrogen chains.
The new synthesis pathway functions under very mild conditions: at minus 30 degrees Celsius and under a moderate pressure of nitrogen (around four atmospheres). It also does not require a transition metal catalyst, unlike almost all biological and industrial reactions of nitrogen.
"This will open the way to a chemistry with which completely new chain-form nitrogen molecules can be synthesized," says JMU chemistry Professor Holger Braunschweig. For the first time, nitrogen chains containing a special variant of nitrogen (15N isotope) can also be easily produced.
The reductive coupling of dinitrogen (DOI: 10.1126/science.aav9593) (DX)
(Score: 2) by stormwyrm on Thursday March 28 2019, @07:52AM (1 child)
Numquam ponenda est pluralitas sine necessitate.
(Score: 3, Insightful) by richtopia on Thursday March 28 2019, @04:21PM
It will come down to the energy required. If this new pathway takes less energy, there could be serious savings. The world spends a LOT on making ammonia: approximately 3-5% of natural gas is consumed on the Haber process, which is about 1-2% of the total energy supply. Yes, boron is expensive, but at the production volumes we could be looking at mining boron could be justified.