50% of the nitrogen in our bodies came from the Haber–Bosch process. It’s in every protein and every strand of DNA. Ponder that — “50% of the nitrogen in your blood, your skin and hair, your proteins and DNA, is synthetic.” The Haber-Bosch process catalyzes the production of ammonia (NH3) from N2 and H2 gas. We need “fixed nitrogen”, available to our organic chemistries as atomic nitrogen. It is the limiting factor for the growth of all food. While nitrogen gas is about 80% of our atmosphere, not one atom of it is available for our use when tightly bound by the triple bond of N2 gas, the strongest chemical bond in nature. It is sequestered all around us. In nature, N2 is liberated to atomic nitrogen in small amounts by lightning strikes (it needs 1000°C) and slowly by nitrogen-fixing bacteria in the soil. Hager argues that if we reverted to relying on just those natural sources, 3b people would die of starvation in short order — our soils simply could not produce enough food for the mouths now on Earth. The Haber process consumes 4% of the world’s natural-gas production and 1.5% of the world’s energy supply.

2021-11-30: There’s a potential replacement:

The process is as clean as the electricity used to power it, and produces around 53 nanomoles of ammonia per second, at Faradaic efficiencies around 69%. The highest reported previous efficiencies for ammonia electrolysis sat around 60%, with the exception of 1 other lithium cycling approach that managed 88%, but required high temperatures of 450 °C. The team says it’s massively scalable, capable of operating either at industrial scale, or in extremely small on-site operations. “They can be as small as a thick iPad, and that could make a small amount of ammonia continuously to run a commercial greenhouse or hydroponics setup, for example.” This kind of distributed production model, as we explored looking at FuelPositive’s modular, container-sized ammonia production units, would have additional benefits in that it would eliminate the distribution and transport that contribute significantly to the financial and emissions costs of the current ammonia model.

2022-05-04: What happens when you think you can do without Haber-Bosch.
2022-07-22: The same team was able to improve ammonia electrolysis further, with 3x yield and nearly 100% energy efficiency.

We investigate the role of the electrolyte in this reaction and present a high-efficiency, robust process enabled by compact ionic layering in the electrode-electrolyte interfacial region. The interface is generated by a high-concentration imide-based lithium salt electrolyte, enabling stabilized ammonia yield rates of 150±20 nmol s-1 cm-2 and current-to-ammonia efficiency closely approaching 100%.

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