High efficiency NOx synthesis and regulation using dielectric barrier discharge in the needle array packed bed reactor

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2023-04, Vol.461, p.141922, Article 141922
• Main Authors: Li, Yao, Qin, Liang, Wang, Hong-Li, Li, Si-Si, Yuan, Hao, Yang, De-Zheng
• Format: Article
• Language: English
• Subjects: Discharge parameter; Non-thermal plasma; NOx synthesis; Packed bed dielectric barrier discharge; Product selectivity
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2023.141922

[Display omitted] •The nanosecond pulse discharge plasma in needle array packed bed reactor is presented to enhance NOx synthesis efficiency.•The highest NOx concentration of 1.1 % and 0.97 % with the low energy cost of 17 MJ/mol and 33 MJ/mol is obtained in unfilled reactor and γ-Al2O3 packed bed reactor, respectively.•The discharge power, reactive species, and discharge area are important factors for NOx synthesis.•The NOx synthesis results can be regulated effectively by adjusting discharge parameters and oxygen content. High efficiency NOx synthesis by plasma technology is the key objective in the field of nitrogen fixation currently. In this paper, a needle array packed bed reactor excited by nanosecond pulse voltage is employed to synthesize NOx efficiently with α-Al2O3 and γ-Al2O3 packed materials. The pulse width, pulse rising time, pulse repetition rate, and oxygen content are adjusted to regulate the NOx synthesis results, such as NOx concentration, product selectivity, and energy cost. The discharge power, key reactive species, and the rate coefficient are calculated to provide clear insight into the NOx synthesis pathways. It is found that the NOx can be synthesized efficiently in this needle-tubes array packed bed reactor, the highest NOx concentration of 1.12% and 0.97% are obtained in unfilled reactor and γ-Al2O3 packed bed reactor, respectively, which are nearly-two times higher than the results reported in previous works under the same energy cost and the same type of discharge. In addition, increasing pulse width and pulse repetition rate can significantly enhance the NOx concentrations because of the increased energy input and rate coefficient.