Site items in: Plasma

Ammonia Yields during Plasma-Assisted Catalysis Boosted By Hydrogen Sink Effect
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Ammonia Yields during Plasma-Assisted Catalysis Boosted By Hydrogen Sink Effect

Maria Carreon November 14, 2019

Plasma-catalytic ammonia synthesis is known since early 1900s but the possible reaction pathways are currently under investigation. In this article, we present the use of various transition metals and gallium-rich alloys for plasma-catalytic ammonia synthesis. The best three metallic catalysts were identified to be Ni, Sn and Au with the highest ammonia yield of 34%. Furthermore, as compared to its constituent metals some alloys presented about 25-50% better yields. The metals employed were classified in two different categories according to their behavior during ammonia plasma-catalysis. Category I metals are nitrophobic and the measured concentration of Hα in the gas phase…

Paper

Synthesis of Ammonia By RF Non-Thermal Plasma over Ni-MOF-74

Maria Carreon November 12, 2019

Herein, we demonstrate a synergistic approach consisting on radiofrequency plasma to synthesize ammonia in the presence of Ni-MOF-74 as catalyst. The Ni-MOF displayed higher ammonia yields as com-pared to the pure Ni metal. Specifically, ammonia yields as high as 0.23 g-NH3 (kWh-g-catalyst)-1 and energy cost of 265 MJ mol-1 over Ni-MOF were observed. The enhanced catalytic activity of the Ni-MOF in the presence of plasma was attributed to the presence of pores that improved mass transfer of guest and product molecules during reaction, the presence of open Ni metal sites, and lower surface hydrogen re-combination. Furthermore, the ammonia energy yield…

Microwave Catalysis for Ammonia Synthesis Under Mild Reaction Conditions
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Microwave Catalysis for Ammonia Synthesis Under Mild Reaction Conditions

Jianli HuHanjing TianYan LuoXinwei BaiDushyant ShekhawatChristina WildfireVictor AbdelsayedMichael J. SpencerRobert A. DagleStephen DavidsonAlbert E. Stiegman October 31, 2018

A scalable, cost-effective catalytic process of ammonia synthesis is developed by using microwave excitation under mild reaction conditions. In this research project funded by DOE ARPA-E, our interdisciplinary team of WVU, NETL, PNNL, FSU and two industrial partners have demonstrated that ammonia synthesis can be carried out at 200-300 °C and ambient pressure. This transformational process integrates system elements of electromagnetic sensitive catalysts and microwave reactor design. Taking advantages of state-of-the art non-equilibrium microwave plasma technology, catalytic ammonia synthesis undergoes a new reaction pathway where the barrier for the initial dissociation of the dinitrogen is decoupled from the bonding energy…

Ammonia Synthesis Via Radiofrequency Plasma Catalysis
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Ammonia Synthesis Via Radiofrequency Plasma Catalysis

Javishk ShahMaria CarreonWeizong WangAnnemie Bogaerts October 31, 2018

Introduction: In 1909, a compound named Ammonia was discovered. Through the 20th century, the immense potential of this chemical was exploited by using in almost every product, from process industry for fertilizer and chemical production to every use in cosmetics, household cleaners and medicines. Recently, fuel cells operating on liquid ammonia as working fluid have been developed on research scale. Despite of using 1-2% of total energy production for the synthesis of this compound, no significant changes have been made to the process since the first Haber-Bosch process plant has been setup. Plasma catalysis is the use of plasma and…

Atmospheric-Pressure Synthesis of Ammonia Using Non-Thermal Plasma with the Assistance of Ru-Based Multifunctional Catalyst
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Atmospheric-Pressure Synthesis of Ammonia Using Non-Thermal Plasma with the Assistance of Ru-Based Multifunctional Catalyst

Peng PengYanling ChengNan ZhouRaymond HatzenbellerPaul ChenRoger Ruan November 2, 2017

Ammonia has much more uses than being a fertilizer. Its emerging applications include hydrogen carrier, fuel cells, clean transportation fuels, and other off-grid power applications. The traditional Haber Bosch process used to synthesize ammonia must be achieved at high temperature and pressure. The non-thermal plasma (NTP) allows for the synthesis of ammonia at a lower temperature and pressure conditions. It is proposed that the moderate process conditions can potentially allow a more economical construction and operation of ammonia production systems on distributed farms and renewable hydrogen production sites. In this study, we report the NTP synthesis of ammonia using dielectric…