2026 Volume 69 Issue 5 Pages 260-264
Nitrogen fixation is essential for modern food production, yet the conventional Haber–Bosch process requires high temperature and pressure and involves significant energy consumption and CO2 emissions. This article reviews nitrogen oxide (NOx) formation in air thermal plasmas generated by a direct-current arc, focusing on reaction field design and energy efficiency. Air thermal plasmas create high-temperature conditions that activate nitrogen and oxygen, leading to reactive nitrogen species. Key factors affecting NOx generation, including energy input, gas flow conditions, and energy consumption per unit nitrogen production, are outlined together with representative experimental trends relating arc current, NOx concentration, and energy consumption.
The feasibility of plasma-driven nitrogen fixation as a decentralized, electricity-based process is discussed. Its operational flexibility and compatibility with renewable energy sources suggest potential for distributed fertilizer production, while further improvements in energy efficiency remain necessary.