Synthesis of Higher-Order Nitrogen-Containing Organic Compounds from Butylamine Using a Microsecond Pulse Dielectric Barrier Discharge

Synthesis of nitrogen-containing organic compounds (NOCs), especially higher-order NOCs, is very energy intensive, and traditional methods emit a high amount of CO2 equivalents into the environment. To lower emissions and alleviate the energy requirements of the process, we propose the use of gas over liquid non-thermal plasma (NTP) as a substitute. In this work, we investigate the formation of higher-order NOCs from butylamine and subsequently study the process's changing reaction chemistry with gas mixtures, reactor temperature, and treatment time. Different compounds in the form of aliphatic and aromatic amines, nitriles, and azoles were observed. Under the optimized conditions, our proposed reactor was able to achieve a production efficiency of 49.4 g/kWh with pure argon gas at -20 degrees C. The selectivity of the products varied with gas mixtures, reactor temperature, and treatment time due to altering reaction pathways which are discussed in more detail. An insight into the dielectric barrier discharge (DBD) conditions for obtaining different plasma chemistry in NOC synthesis can thus provide a foundation to develop a novel synthetic approach.